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提交 4c34bc07 authored 作者: Thomas Mueller's avatar Thomas Mueller
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A persistent multi-version map: move to the main source tree

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h2/src/tools/org/h2/dev/store/btree/ChangeCursor.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
import java.util.Iterator;
/**
* A cursor to iterate over all keys in new pages.
*
* @param <K> the key type
* @param <V> the value type
*/
public class ChangeCursor<K, V> implements Iterator<K> {
private final MVMap<K, V> map;
private final Page root1, root2;
/**
* The state of this cursor.
* 0: not initialized
* 1: reading from root1
* 2: reading from root2
* 3: closed
*/
private int state;
private CursorPos pos1, pos2;
private K current;
ChangeCursor(MVMap<K, V> map, Page root1, Page root2) {
this.map = map;
this.root1 = root1;
this.root2 = root2;
}
public K next() {
K c = current;
fetchNext();
return c;
}
public boolean hasNext() {
if (state == 0) {
pos1 = new CursorPos(root1, 0, null);
pos1 = min(pos1);
state = 1;
fetchNext();
}
return current != null;
}
public void remove() {
throw new UnsupportedOperationException();
}
private void fetchNext() {
while (fetchNextKey()) {
if (pos1 == null || pos2 == null) {
break;
}
@SuppressWarnings("unchecked")
V v1 = (V) map.binarySearch(root1, current);
@SuppressWarnings("unchecked")
V v2 = (V) map.binarySearch(root2, current);
if (!v1.equals(v2)) {
break;
}
}
}
private boolean fetchNextKey() {
while (true) {
if (state == 3) {
return false;
}
if (state == 1) {
// read from root1
pos1 = fetchNext(pos1);
if (pos1 == null) {
// reached the end of pos1
state = 2;
pos2 = null;
continue;
}
pos2 = find(root2, current);
if (pos2 == null) {
// not found in root2
return true;
}
if (!pos1.page.equals(pos2.page)) {
// the page is different,
// so the entry has possibly changed
return true;
}
while (true) {
pos1 = pos1.parent;
if (pos1 == null) {
// reached end of pos1
state = 2;
pos2 = null;
break;
}
pos2 = pos2.parent;
if (pos2 == null || !pos1.page.equals(pos2.page)) {
if (pos1.index + 1 < map.getChildPageCount(pos1.page)) {
pos1 = new CursorPos(pos1.page.getChildPage(++pos1.index), 0, pos1);
pos1 = min(pos1);
break;
}
}
}
}
if (state == 2) {
if (pos2 == null) {
// init reading from root2
pos2 = new CursorPos(root2, 0, null);
pos2 = min(pos2);
}
// read from root2
pos2 = fetchNext(pos2);
if (pos2 == null) {
// reached the end of pos2
state = 3;
current = null;
continue;
}
pos1 = find(root1, current);
if (pos1 != null) {
// found a corresponding record
// so it was not deleted
// but now we may need to skip pages
if (!pos1.page.equals(pos2.page)) {
// the page is different
pos1 = null;
continue;
}
while (true) {
pos2 = pos2.parent;
if (pos2 == null) {
// reached end of pos1
state = 3;
current = null;
pos1 = null;
break;
}
pos1 = pos1.parent;
if (pos1 == null || !pos2.page.equals(pos1.page)) {
if (pos2.index + 1 < map.getChildPageCount(pos2.page)) {
pos2 = new CursorPos(pos2.page.getChildPage(++pos2.index), 0, pos2);
pos2 = min(pos2);
break;
}
}
}
pos1 = null;
continue;
}
// found no corresponding record
// so it was deleted
return true;
}
}
}
private CursorPos find(Page p, K key) {
// TODO combine with RangeCursor.min
// possibly move to MVMap
CursorPos pos = null;
while (true) {
if (p.isLeaf()) {
int x = key == null ? 0 : p.binarySearch(key);
if (x < 0) {
return null;
}
return new CursorPos(p, x, pos);
}
int x = key == null ? -1 : p.binarySearch(key);
if (x < 0) {
x = -x - 1;
} else {
x++;
}
pos = new CursorPos(p, x, pos);
p = p.getChildPage(x);
}
}
@SuppressWarnings("unchecked")
private CursorPos fetchNext(CursorPos p) {
while (p != null) {
if (p.index < p.page.getKeyCount()) {
current = (K) p.page.getKey(p.index++);
return p;
}
p = p.parent;
if (p == null) {
break;
}
if (p.index + 1 < map.getChildPageCount(p.page)) {
p = new CursorPos(p.page.getChildPage(++p.index), 0, p);
p = min(p);
}
}
current = null;
return p;
}
private static CursorPos min(CursorPos p) {
while (true) {
if (p.page.isLeaf()) {
return p;
}
Page c = p.page.getChildPage(0);
p = new CursorPos(c, 0, p);
}
}
}
h2/src/tools/org/h2/dev/store/btree/Chunk.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
import java.nio.ByteBuffer;
import java.util.HashMap;
/**
* A chunk of data, containing one or multiple pages.
* <p>
* Chunks are page aligned (each page is usually 4096 bytes).
* There are at most 67 million (2^26) chunks,
* each chunk is at most 2 GB large.
* File format:
* 1 byte: 'c'
* 4 bytes: length
* 4 bytes: chunk id (an incrementing number)
* 4 bytes: pageCount
* 8 bytes: metaRootPos
* 8 bytes: maxLengthLive
* [ Page ] *
*/
public class Chunk {
/**
* The chunk id.
*/
final int id;
/**
* The start position within the file.
*/
long start;
/**
* The length in bytes.
*/
int length;
/**
* The number of pages.
*/
int pageCount;
/**
* The sum of the max length of all pages.
*/
long maxLength;
/**
* The sum of the max length of all pages that are in use.
*/
long maxLengthLive;
/**
* The garbage collection priority.
*/
int collectPriority;
/**
* The position of the meta root.
*/
long metaRootPos;
/**
* The version stored in this chunk.
*/
long version;
Chunk(int id) {
this.id = id;
}
/**
* Read the header from the byte buffer.
*
* @param buff the source buffer
* @param start the start of the chunk in the file
* @return the chunk
*/
static Chunk fromHeader(ByteBuffer buff, long start) {
if (buff.get() != 'c') {
throw new RuntimeException("File corrupt");
}
int length = buff.getInt();
int chunkId = buff.getInt();
int pageCount = buff.getInt();
long metaRootPos = buff.getLong();
long maxLength = buff.getLong();
long maxLengthLive = buff.getLong();
Chunk c = new Chunk(chunkId);
c.length = length;
c.pageCount = pageCount;
c.start = start;
c.metaRootPos = metaRootPos;
c.maxLength = maxLength;
c.maxLengthLive = maxLengthLive;
return c;
}
/**
* Write the header.
*
* @param buff the target buffer
*/
void writeHeader(ByteBuffer buff) {
buff.put((byte) 'c');
buff.putInt(length);
buff.putInt(id);
buff.putInt(pageCount);
buff.putLong(metaRootPos);
buff.putLong(maxLength);
buff.putLong(maxLengthLive);
}
/**
* Build a block from the given string.
*
* @param s the string
* @return the block
*/
public static Chunk fromString(String s) {
HashMap<String, String> map = DataUtils.parseMap(s);
int id = Integer.parseInt(map.get("id"));
Chunk c = new Chunk(id);
c.start = Long.parseLong(map.get("start"));
c.length = Integer.parseInt(map.get("length"));
c.pageCount = Integer.parseInt(map.get("pageCount"));
c.maxLength = Long.parseLong(map.get("maxLength"));
c.maxLengthLive = Long.parseLong(map.get("maxLengthLive"));
c.metaRootPos = Long.parseLong(map.get("metaRoot"));
c.version = Long.parseLong(map.get("version"));
return c;
}
public int getFillRate() {
return (int) (maxLength == 0 ? 0 : 100 * maxLengthLive / maxLength);
}
public int hashCode() {
return id;
}
public boolean equals(Object o) {
return o instanceof Chunk && ((Chunk) o).id == id;
}
/**
* Get the chunk data as a string.
*
* @return the string
*/
public String asString() {
return
"id:" + id + "," +
"start:" + start + "," +
"length:" + length + "," +
"pageCount:" + pageCount + "," +
"maxLength:" + maxLength + "," +
"maxLengthLive:" + maxLengthLive + "," +
"metaRoot:" + metaRootPos + "," +
"version:" + version;
}
}
h2/src/tools/org/h2/dev/store/btree/Cursor.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
import java.util.Iterator;
/**
* A cursor to iterate over elements in ascending order.
*
* @param <K> the key type
*/
public class Cursor<K> implements Iterator<K> {
protected final MVMap<K, ?> map;
protected final K from;
protected CursorPos pos;
protected K current;
private final Page root;
private boolean initialized;
protected Cursor(MVMap<K, ?> map, Page root, K from) {
this.map = map;
this.root = root;
this.from = from;
}
public K next() {
hasNext();
K c = current;
fetchNext();
return c;
}
public boolean hasNext() {
if (!initialized) {
min(root, from);
initialized = true;
fetchNext();
}
return current != null;
}
/**
* Skip over that many entries. This method is relatively fast (for this map
* implementation) even if many entries need to be skipped.
*
* @param n the number of entries to skip
*/
public void skip(long n) {
if (!hasNext()) {
return;
}
if (n < 10) {
while (n-- > 0) {
fetchNext();
}
return;
}
long index = map.getKeyIndex(current);
K k = map.getKey(index + n);
min(root, k);
fetchNext();
}
public void remove() {
throw new UnsupportedOperationException();
}
/**
* Fetch the next entry that is equal or larger than the given key, starting
* from the given page.
*
* @param p the page to start
* @param from the key to search
*/
protected void min(Page p, K from) {
while (true) {
if (p.isLeaf()) {
int x = from == null ? 0 : p.binarySearch(from);
if (x < 0) {
x = -x - 1;
}
pos = new CursorPos(p, x, pos);
break;
}
int x = from == null ? -1 : p.binarySearch(from);
if (x < 0) {
x = -x - 1;
} else {
x++;
}
pos = new CursorPos(p, x + 1, pos);
p = p.getChildPage(x);
}
}
/**
* Fetch the next entry if there is one.
*/
@SuppressWarnings("unchecked")
protected void fetchNext() {
while (pos != null) {
if (pos.index < pos.page.getKeyCount()) {
current = (K) pos.page.getKey(pos.index++);
return;
}
pos = pos.parent;
if (pos == null) {
break;
}
if (pos.index < map.getChildPageCount(pos.page)) {
min(pos.page.getChildPage(pos.index++), null);
}
}
current = null;
}
}
h2/src/tools/org/h2/dev/store/btree/CursorPos.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
/**
* A position in a cursor
*/
public class CursorPos {
/**
* The current page.
*/
public final Page page;
/**
* The current index.
*/
public int index;
/**
* The position in the parent page, if any.
*/
public final CursorPos parent;
public CursorPos(Page page, int index, CursorPos parent) {
this.page = page;
this.index = index;
this.parent = parent;
}
}
h2/src/tools/org/h2/dev/store/btree/DataUtils.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
import java.io.EOFException;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import org.h2.util.New;
/**
* Utility methods
*/
public class DataUtils {
/**
* The type for leaf page.
*/
public static final int PAGE_TYPE_LEAF = 0;
/**
* The type for node page.
*/
public static final int PAGE_TYPE_NODE = 1;
/**
* The bit mask for compressed pages.
*/
public static final int PAGE_COMPRESSED = 2;
/**
* The maximum length of a variable size int.
*/
public static final int MAX_VAR_INT_LEN = 5;
/**
* The maximum length of a variable size long.
*/
public static final int MAX_VAR_LONG_LEN = 10;
/**
* The maximum integer that needs less space when using variable size
* encoding (only 3 bytes instead of 4).
*/
public static final int COMPRESSED_VAR_INT_MAX = 0x1fffff;
/**
* The maximum long that needs less space when using variable size
* encoding (only 7 bytes instead of 8).
*/
public static final long COMPRESSED_VAR_LONG_MAX = 0x1ffffffffffffL;
/**
* The estimated number of bytes used per page object.
*/
public static final int PAGE_MEMORY = 128;
/**
* The estimated number of bytes used per child entry.
*/
public static final int PAGE_MEMORY_CHILD = 16;
/**
* Get the length of the variable size int.
*
* @param x the value
* @return the length in bytes
*/
public static int getVarIntLen(int x) {
if ((x & (-1 << 7)) == 0) {
return 1;
} else if ((x & (-1 << 14)) == 0) {
return 2;
} else if ((x & (-1 << 21)) == 0) {
return 3;
} else if ((x & (-1 << 28)) == 0) {
return 4;
}
return 5;
}
/**
* Get the length of the variable size long.
*
* @param x the value
* @return the length in bytes
*/
public static int getVarLongLen(long x) {
int i = 1;
while (true) {
x >>>= 7;
if (x == 0) {
return i;
}
i++;
}
}
/**
* Read a variable size int.
*
* @param buff the source buffer
* @return the value
*/
public static int readVarInt(ByteBuffer buff) {
int b = buff.get();
if (b >= 0) {
return b;
}
// a separate function so that this one can be inlined
return readVarIntRest(buff, b);
}
private static int readVarIntRest(ByteBuffer buff, int b) {
int x = b & 0x7f;
b = buff.get();
if (b >= 0) {
return x | (b << 7);
}
x |= (b & 0x7f) << 7;
b = buff.get();
if (b >= 0) {
return x | (b << 14);
}
x |= (b & 0x7f) << 14;
b = buff.get();
if (b >= 0) {
return x | b << 21;
}
x |= ((b & 0x7f) << 21) | (buff.get() << 28);
return x;
}
/**
* Read a variable size long.
*
* @param buff the source buffer
* @return the value
*/
public static long readVarLong(ByteBuffer buff) {
long x = buff.get();
if (x >= 0) {
return x;
}
x &= 0x7f;
for (int s = 7; s < 64; s += 7) {
long b = buff.get();
x |= (b & 0x7f) << s;
if (b >= 0) {
break;
}
}
return x;
}
/**
* Write a variable size int.
*
* @param out the output stream
* @param x the value
*/
public static void writeVarInt(OutputStream out, int x) throws IOException {
while ((x & ~0x7f) != 0) {
out.write((byte) (0x80 | (x & 0x7f)));
x >>>= 7;
}
out.write((byte) x);
}
/**
* Write a variable size int.
*
* @param buff the source buffer
* @param x the value
*/
public static void writeVarInt(ByteBuffer buff, int x) {
while ((x & ~0x7f) != 0) {
buff.put((byte) (0x80 | (x & 0x7f)));
x >>>= 7;
}
buff.put((byte) x);
}
/**
* Write characters from a string (without the length).
*
* @param buff the target buffer
* @param s the string
* @param len the number of characters
*/
public static void writeStringData(ByteBuffer buff, String s, int len) {
for (int i = 0; i < len; i++) {
int c = s.charAt(i);
if (c < 0x80) {
buff.put((byte) c);
} else if (c >= 0x800) {
buff.put((byte) (0xe0 | (c >> 12)));
buff.put((byte) (((c >> 6) & 0x3f)));
buff.put((byte) (c & 0x3f));
} else {
buff.put((byte) (0xc0 | (c >> 6)));
buff.put((byte) (c & 0x3f));
}
}
}
/**
* Read a string.
*
* @param buff the source buffer
* @param len the number of characters
* @return the value
*/
public static String readString(ByteBuffer buff, int len) {
char[] chars = new char[len];
for (int i = 0; i < len; i++) {
int x = buff.get() & 0xff;
if (x < 0x80) {
chars[i] = (char) x;
} else if (x >= 0xe0) {
chars[i] = (char) (((x & 0xf) << 12) + ((buff.get() & 0x3f) << 6) + (buff.get() & 0x3f));
} else {
chars[i] = (char) (((x & 0x1f) << 6) + (buff.get() & 0x3f));
}
}
return new String(chars);
}
/**
* Write a variable size long.
*
* @param buff the target buffer
* @param x the value
*/
public static void writeVarLong(ByteBuffer buff, long x) {
while ((x & ~0x7f) != 0) {
buff.put((byte) (0x80 | (x & 0x7f)));
x >>>= 7;
}
buff.put((byte) x);
}
/**
* Write a variable size long.
*
* @param out the output stream
* @param x the value
*/
public static void writeVarLong(OutputStream out, long x) throws IOException {
while ((x & ~0x7f) != 0) {
out.write((byte) (0x80 | (x & 0x7f)));
x >>>= 7;
}
out.write((byte) x);
}
/**
* Copy the elements of an array, with a gap.
*
* @param src the source array
* @param dst the target array
* @param oldSize the size of the old array
* @param gapIndex the index of the gap
*/
public static void copyWithGap(Object src, Object dst, int oldSize, int gapIndex) {
if (gapIndex > 0) {
System.arraycopy(src, 0, dst, 0, gapIndex);
}
if (gapIndex < oldSize) {
System.arraycopy(src, gapIndex, dst, gapIndex + 1, oldSize - gapIndex);
}
}
/**
* Copy the elements of an array, and remove one element.
*
* @param src the source array
* @param dst the target array
* @param oldSize the size of the old array
* @param removeIndex the index of the entry to remove
*/
public static void copyExcept(Object src, Object dst, int oldSize, int removeIndex) {
if (removeIndex > 0 && oldSize > 0) {
System.arraycopy(src, 0, dst, 0, removeIndex);
}
if (removeIndex < oldSize) {
System.arraycopy(src, removeIndex + 1, dst, removeIndex, oldSize - removeIndex - 1);
}
}
/**
* Read from a file channel until the buffer is full, or end-of-file
* has been reached. The buffer is rewind at the end.
*
* @param file the file channel
* @param pos the absolute position within the file
* @param dst the byte buffer
*/
public static void readFully(FileChannel file, long pos, ByteBuffer dst) throws IOException {
do {
int len = file.read(dst, pos);
if (len < 0) {
throw new EOFException();
}
pos += len;
} while (dst.remaining() > 0);
dst.rewind();
}
/**
* Write to a file channel.
*
* @param file the file channel
* @param pos the absolute position within the file
* @param src the source buffer
*/
public static void writeFully(FileChannel file, long pos, ByteBuffer src) throws IOException {
int off = 0;
do {
int len = file.write(src, pos + off);
off += len;
} while (src.remaining() > 0);
}
/**
* Convert the length to a length code 0..31. 31 means more than 1 MB.
*
* @param len the length
* @return the length code
*/
public static int encodeLength(int len) {
if (len <= 32) {
return 0;
}
int x = len;
int shift = 0;
while (x > 3) {
shift++;
x = (x >> 1) + (x & 1);
}
shift = Math.max(0, shift - 4);
int code = (shift << 1) + (x & 1);
return Math.min(31, code);
}
/**
* Get the chunk id from the position.
*
* @param pos the position
* @return the chunk id
*/
public static int getPageChunkId(long pos) {
return (int) (pos >>> 38);
}
/**
* Get the maximum length for the given code.
* For the code 31, Integer.MAX_VALUE is returned.
*
* @param pos the position
* @return the maximum length
*/
public static int getPageMaxLength(long pos) {
int code = (int) ((pos >> 1) & 31);
if (code == 31) {
return Integer.MAX_VALUE;
}
return (2 + (code & 1)) << ((code >> 1) + 4);
}
/**
* Get the offset from the position.
*
* @param pos the position
* @return the offset
*/
public static int getPageOffset(long pos) {
return (int) (pos >> 6);
}
/**
* Get the page type from the position.
*
* @param pos the position
* @return the page type (PAGE_TYPE_NODE or PAGE_TYPE_LEAF)
*/
public static int getPageType(long pos) {
return ((int) pos) & 1;
}
/**
* Get the position of this page. The following information is encoded in
* the position: the chunk id, the offset, the maximum length, and the type
* (node or leaf).
*
* @param chunkId the chunk id
* @param offset the offset
* @param length the length
* @param type the page type (1 for node, 0 for leaf)
* @return the position
*/
public static long getPagePos(int chunkId, int offset, int length, int type) {
long pos = (long) chunkId << 38;
pos |= (long) offset << 6;
pos |= encodeLength(length) << 1;
pos |= type;
return pos;
}
/**
* Calculate a check value for the given integer. A check value is mean to
* verify the data is consistent with a high probability, but not meant to
* protect against media failure or deliberate changes.
*
* @param x the value
* @return the check value
*/
public static short getCheckValue(int x) {
return (short) ((x >> 16) ^ x);
}
/**
* Append a map to the string builder, sorted by key.
*
* @param buff the target buffer
* @param map the map
* @return the string builder
*/
public static StringBuilder appendMap(StringBuilder buff, HashMap<String, ?> map) {
ArrayList<String> list = New.arrayList(map.keySet());
Collections.sort(list);
for (String k : list) {
appendMap(buff, k, map.get(k));
}
return buff;
}
/**
* Append a key-value pair to the string builder. Keys may not contain a
* colon. Values that contain a comma or a double quote are enclosed in
* double quotes, with special characters escaped using a backslash.
*
* @param buff the target buffer
* @param key the key
* @param value the value
*/
public static void appendMap(StringBuilder buff, String key, Object value) {
if (buff.length() > 0) {
buff.append(',');
}
buff.append(key).append(':');
String v = value.toString();
if (v.indexOf(',') < 0 && v.indexOf('\"') < 0) {
buff.append(value);
} else {
buff.append('\"');
for (int i = 0, size = v.length(); i < size; i++) {
char c = v.charAt(i);
if (c == '\"') {
buff.append('\\');
}
buff.append(c);
}
buff.append('\"');
}
}
/**
* Parse a key-value pair list.
*
* @param s the list
* @return the map
*/
public static HashMap<String, String> parseMap(String s) {
HashMap<String, String> map = New.hashMap();
for (int i = 0, size = s.length(); i < size;) {
int startKey = i;
i = s.indexOf(':', i);
String key = s.substring(startKey, i++);
StringBuilder buff = new StringBuilder();
while (i < size) {
char c = s.charAt(i++);
if (c == ',') {
break;
} else if (c == '\"') {
while (i < size) {
c = s.charAt(i++);
if (c == '\\') {
c = s.charAt(i++);
} else if (c == '\"') {
break;
}
buff.append(c);
}
} else {
buff.append(c);
}
}
map.put(key, buff.toString());
}
return map;
}
/**
* Calculate the Fletcher32 checksum.
*
* @param bytes the bytes
* @param length the message length (must be a multiple of 2)
* @return the checksum
*/
public static int getFletcher32(byte[] bytes, int length) {
int s1 = 0xffff, s2 = 0xffff;
for (int i = 0; i < length;) {
for (int end = Math.min(i + 718, length); i < end;) {
int x = ((bytes[i++] & 0xff) << 8) | (bytes[i++] & 0xff);
s2 += s1 += x;
}
s1 = (s1 & 0xffff) + (s1 >>> 16);
s2 = (s2 & 0xffff) + (s2 >>> 16);
}
s1 = (s1 & 0xffff) + (s1 >>> 16);
s2 = (s2 & 0xffff) + (s2 >>> 16);
return (s2 << 16) | s1;
}
}
h2/src/tools/org/h2/dev/store/btree/MVMap.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
import java.util.AbstractList;
import java.util.AbstractMap;
import java.util.AbstractSet;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentMap;
import org.h2.dev.store.type.DataType;
import org.h2.util.New;
/**
* A stored map.
*
* @param <K> the key class
* @param <V> the value class
*/
public class MVMap<K, V> extends AbstractMap<K, V>
implements ConcurrentMap<K, V> {
/**
* The store.
*/
protected MVStore store;
/**
* The current root page (may not be null).
*/
protected volatile Page root;
private int id;
private String name;
private long createVersion;
private final DataType keyType;
private final DataType valueType;
private ArrayList<Page> oldRoots = new ArrayList<Page>();
private boolean closed;
private boolean readOnly;
public MVMap(DataType keyType, DataType valueType) {
this.keyType = keyType;
this.valueType = valueType;
this.root = Page.createEmpty(this, -1);
}
/**
* Open this map with the given store and configuration.
*
* @param store the store
* @param config the configuration
*/
public void open(MVStore store, HashMap<String, String> config) {
this.store = store;
this.id = Integer.parseInt(config.get("id"));
this.name = config.get("name");
this.createVersion = Long.parseLong(config.get("createVersion"));
}
/**
* Add or replace a key-value pair.
*
* @param key the key (may not be null)
* @param value the value (may not be null)
* @return the old value if the key existed, or null otherwise
*/
@SuppressWarnings("unchecked")
public V put(K key, V value) {
checkWrite();
long writeVersion = store.getCurrentVersion();
Page p = root.copyOnWrite(writeVersion);
if (p.getMemory() > store.getPageSize() && p.getKeyCount() > 1) {
int at = p.getKeyCount() / 2;
long totalCount = p.getTotalCount();
Object k = p.getKey(at);
Page split = p.split(at);
Object[] keys = { k };
long[] children = { p.getPos(), split.getPos() };
Page[] childrenPages = { p, split };
long[] counts = { p.getTotalCount(), split.getTotalCount() };
p = Page.create(this, writeVersion, 1,
keys, null, children, childrenPages, counts, totalCount, 0, 0);
store.registerUnsavedPage();
// now p is a node; insert continues
}
Object result = put(p, writeVersion, key, value);
newRoot(p);
return (V) result;
}
/**
* Add or update a key-value pair.
*
* @param p the page
* @param writeVersion the write version
* @param key the key (may not be null)
* @param value the value (may not be null)
* @return the old value, or null
*/
protected Object put(Page p, long writeVersion, Object key, Object value) {
if (p.isLeaf()) {
int index = p.binarySearch(key);
if (index < 0) {
index = -index - 1;
p.insertLeaf(index, key, value);
return null;
}
return p.setValue(index, value);
}
// p is a node
int index = p.binarySearch(key);
if (index < 0) {
index = -index - 1;
} else {
index++;
}
Page c = p.getChildPage(index).copyOnWrite(writeVersion);
if (c.getMemory() > store.getPageSize() && c.getKeyCount() > 1) {
// split on the way down
int at = c.getKeyCount() / 2;
Object k = c.getKey(at);
Page split = c.split(at);
p.setChild(index, split);
p.insertNode(index, k, c);
// now we are not sure where to add
return put(p, writeVersion, key, value);
}
Object result = put(c, writeVersion, key, value);
p.setChild(index, c);
return result;
}
/**
* Get the first key, or null if the map is empty.
*
* @return the first key, or null
*/
public K firstKey() {
return getFirstLast(true);
}
/**
* Get the last key, or null if the map is empty.
*
* @return the last key, or null
*/
public K lastKey() {
return getFirstLast(false);
}
/**
* Get the key at the given index.
* <p>
* This is a O(log(size)) operation.
*
* @param index the index
* @return the key
*/
@SuppressWarnings("unchecked")
public K getKey(long index) {
checkOpen();
if (index < 0 || index >= size()) {
return null;
}
Page p = root;
long offset = 0;
while (true) {
if (p.isLeaf()) {
if (index >= offset + p.getKeyCount()) {
return null;
}
return (K) p.getKey((int) (index - offset));
}
int i = 0, size = p.getChildPageCount();
for (; i < size; i++) {
long c = p.getCounts(i);
if (index < c + offset) {
break;
}
offset += c;
}
if (i == size) {
return null;
}
p = p.getChildPage(i);
}
}
/**
* Get the key list. The list is a read-only representation of all keys.
* <p>
* The get and indexOf methods are O(log(size)) operations. The result of
* indexOf is cast to an int.
*
* @return the key list
*/
public List<K> keyList() {
return new AbstractList<K>() {
public K get(int index) {
return getKey(index);
}
public int size() {
return MVMap.this.size();
}
@SuppressWarnings("unchecked")
public int indexOf(Object key) {
return (int) getKeyIndex((K) key);
}
};
}
/**
* Get the index of the given key in the map.
* <p>
* This is a O(log(size)) operation.
* <p>
* If the key was found, the returned value is the index in the key array.
* If not found, the returned value is negative, where -1 means the provided
* key is smaller than any keys. See also Arrays.binarySearch.
*
* @param key the key
* @return the index
*/
public long getKeyIndex(K key) {
checkOpen();
if (size() == 0) {
return -1;
}
Page p = root;
long offset = 0;
while (true) {
if (p.isLeaf()) {
int x = p.binarySearch(key);
if (x < 0) {
return -offset + x;
}
return offset + x;
}
int x = key == null ? -1 : p.binarySearch(key);
if (x < 0) {
x = -x - 1;
} else {
x++;
}
for (int i = 0; i < x; i++) {
offset += p.getCounts(i);
}
p = p.getChildPage(x);
}
}
@SuppressWarnings("unchecked")
private K getFirstLast(boolean first) {
checkOpen();
if (size() == 0) {
return null;
}
Page p = root;
while (true) {
if (p.isLeaf()) {
return (K) p.getKey(first ? 0 : p.getKeyCount() - 1);
}
p = p.getChildPage(first ? 0 : p.getChildPageCount() - 1);
}
}
/**
* Get the smallest key that is larger than the given key, or null if no
* such key exists.
*
* @param key the key (may not be null)
* @return the result
*/
public K higherKey(K key) {
return getMinMax(key, false, true);
}
/**
* Get the smallest key that is larger or equal to this key.
*
* @param key the key (may not be null)
* @return the result
*/
public K ceilingKey(K key) {
return getMinMax(key, false, false);
}
/**
* Get the largest key that is smaller or equal to this key.
*
* @param key the key (may not be null)
* @return the result
*/
public K floorKey(K key) {
return getMinMax(key, true, false);
}
/**
* Get the largest key that is smaller than the given key, or null if no
* such key exists.
*
* @param key the key (may not be null)
* @return the result
*/
public K lowerKey(K key) {
return getMinMax(key, true, true);
}
private K getMinMax(K key, boolean min, boolean excluding) {
checkOpen();
if (size() == 0) {
return null;
}
return getMinMax(root, key, min, excluding);
}
@SuppressWarnings("unchecked")
private K getMinMax(Page p, K key, boolean min, boolean excluding) {
if (p.isLeaf()) {
if (key == null) {
return (K) p.getKey(min ? 0 : p.getKeyCount() - 1);
}
int x = p.binarySearch(key);
if (x < 0) {
x = -x - (min ? 2 : 1);
} else if (excluding) {
x += min ? -1 : 1;
}
if (x < 0 || x >= p.getKeyCount()) {
return null;
}
return (K) p.getKey(x);
}
int x;
if (key == null) {
x = min ? 0 : p.getKeyCount() - 1;
} else {
x = p.binarySearch(key);
if (x < 0) {
x = -x - 1;
} else {
x++;
}
}
while (true) {
if (x < 0 || x >= p.getChildPageCount()) {
return null;
}
K k = getMinMax(p.getChildPage(x), key, min, excluding);
if (k != null) {
return k;
}
x += min ? -1 : 1;
}
}
/**
* Get a value.
*
* @param key the key
* @return the value, or null if not found
*/
@SuppressWarnings("unchecked")
public V get(Object key) {
checkOpen();
return (V) binarySearch(root, key);
}
/**
* Get the value for the given key, or null if not found.
*
* @param p the page
* @param key the key
* @return the value or null
*/
protected Object binarySearch(Page p, Object key) {
int x = p.binarySearch(key);
if (!p.isLeaf()) {
if (x < 0) {
x = -x - 1;
} else {
x++;
}
p = p.getChildPage(x);
return binarySearch(p, key);
}
if (x >= 0) {
return p.getValue(x);
}
return null;
}
public boolean containsKey(Object key) {
return get(key) != null;
}
/**
* Get the page for the given value.
*
* @param key the key
* @return the value, or null if not found
*/
protected Page getPage(K key) {
return binarySearchPage(root, key);
}
/**
* Get the value for the given key, or null if not found.
*
* @param p the parent page
* @param key the key
* @return the page or null
*/
protected Page binarySearchPage(Page p, Object key) {
int x = p.binarySearch(key);
if (!p.isLeaf()) {
if (x < 0) {
x = -x - 1;
} else {
x++;
}
p = p.getChildPage(x);
return binarySearchPage(p, key);
}
if (x >= 0) {
return p;
}
return null;
}
/**
* Remove all entries.
*/
public void clear() {
checkWrite();
root.removeAllRecursive();
newRoot(Page.createEmpty(this, store.getCurrentVersion()));
}
/**
* Remove all entries, and close the map.
*/
public void removeMap() {
if (this != store.getMetaMap()) {
checkWrite();
root.removeAllRecursive();
store.removeMap(name);
close();
}
}
/**
* Close the map, making it read only and release the memory.
*/
public void close() {
closed = true;
readOnly = true;
removeAllOldVersions();
root = null;
}
public boolean isClosed() {
return closed;
}
/**
* Remove a key-value pair, if the key exists.
*
* @param key the key (may not be null)
* @return the old value if the key existed, or null otherwise
*/
public V remove(Object key) {
checkWrite();
long writeVersion = store.getCurrentVersion();
Page p = root.copyOnWrite(writeVersion);
@SuppressWarnings("unchecked")
V result = (V) remove(p, writeVersion, key);
newRoot(p);
return result;
}
/**
* Add a key-value pair if it does not yet exist.
*
* @param key the key (may not be null)
* @param value the new value
* @return the old value if the key existed, or null otherwise
*/
public synchronized V putIfAbsent(K key, V value) {
V old = get(key);
if (old == null) {
put(key, value);
}
return old;
}
/**
* Remove a key-value pair if the value matches the stored one.
*
* @param key the key (may not be null)
* @param value the expected value
* @return true if the item was removed
*/
public synchronized boolean remove(Object key, Object value) {
V old = get(key);
if (old.equals(value)) {
remove(key);
return true;
}
return false;
}
/**
* Replace a value for an existing key, if the value matches.
*
* @param key the key (may not be null)
* @param oldValue the expected value
* @param newValue the new value
* @return true if the value was replaced
*/
public synchronized boolean replace(K key, V oldValue, V newValue) {
V old = get(key);
if (old.equals(oldValue)) {
put(key, newValue);
return true;
}
return false;
}
/**
* Replace a value for an existing key.
*
* @param key the key (may not be null)
* @param value the new value
* @return true if the value was replaced
*/
public synchronized V replace(K key, V value) {
V old = get(key);
if (old != null) {
put(key, value);
return old;
}
return null;
}
/**
* Remove a key-value pair.
*
* @param p the page (may not be null)
* @param writeVersion the write version
* @param key the key
* @return the old value, or null if the key did not exist
*/
protected Object remove(Page p, long writeVersion, Object key) {
int index = p.binarySearch(key);
Object result = null;
if (p.isLeaf()) {
if (index >= 0) {
result = p.getValue(index);
p.remove(index);
if (p.getKeyCount() == 0) {
removePage(p);
}
}
return result;
}
// node
if (index < 0) {
index = -index - 1;
} else {
index++;
}
Page cOld = p.getChildPage(index);
Page c = cOld.copyOnWrite(writeVersion);
long oldCount = c.getTotalCount();
result = remove(c, writeVersion, key);
if (oldCount == c.getTotalCount()) {
return null;
}
if (c.getTotalCount() == 0) {
// this child was deleted
if (p.getKeyCount() == 0) {
p.setChild(index, c);
removePage(p);
} else {
p.remove(index);
}
} else {
p.setChild(index, c);
}
return result;
}
/**
* Use the new root page from now on.
*
* @param newRoot the new root page
*/
protected void newRoot(Page newRoot) {
if (root != newRoot) {
removeUnusedOldVersions();
if (root.getVersion() != newRoot.getVersion()) {
ArrayList<Page> list = oldRoots;
if (list.size() > 0) {
Page last = list.get(list.size() - 1);
if (last.getVersion() != root.getVersion()) {
list.add(root);
}
} else {
list.add(root);
}
store.markChanged(this);
}
root = newRoot;
}
}
/**
* Check whether this map has any unsaved changes.
*
* @return true if there are unsaved changes.
*/
public boolean hasUnsavedChanges() {
return !oldRoots.isEmpty();
}
/**
* Compare two keys.
*
* @param a the first key
* @param b the second key
* @return -1 if the first key is smaller, 1 if bigger, 0 if equal
*/
int compare(Object a, Object b) {
return keyType.compare(a, b);
}
/**
* Get the key type.
*
* @return the key type
*/
protected DataType getKeyType() {
return keyType;
}
/**
* Get the value type.
*
* @return the value type
*/
protected DataType getValueType() {
return valueType;
}
/**
* Read a page.
*
* @param pos the position of the page
* @return the page
*/
Page readPage(long pos) {
return store.readPage(this, pos);
}
/**
* Set the position of the root page.
*
* @param rootPos the position, 0 for empty
*/
void setRootPos(long rootPos) {
root = rootPos == 0 ? Page.createEmpty(this, -1) : readPage(rootPos);
}
/**
* Iterate over all keys.
*
* @param from the first key to return
* @return the iterator
*/
public Cursor<K> keyIterator(K from) {
checkOpen();
return new Cursor<K>(this, root, from);
}
/**
* Iterate over all keys in changed pages.
*
* @param version the old version
* @return the iterator
*/
public Iterator<K> changeIterator(long version) {
checkOpen();
MVMap<K, V> old = openVersion(version);
return new ChangeCursor<K, V>(this, root, old.root);
}
public Set<Map.Entry<K, V>> entrySet() {
HashMap<K, V> map = new HashMap<K, V>();
for (K k : keySet()) {
map.put(k, get(k));
}
return map.entrySet();
}
public Set<K> keySet() {
checkOpen();
final MVMap<K, V> map = this;
final Page root = this.root;
return new AbstractSet<K>() {
@Override
public Iterator<K> iterator() {
return new Cursor<K>(map, root, null);
}
@Override
public int size() {
return MVMap.this.size();
}
@Override
public boolean contains(Object o) {
return MVMap.this.containsKey(o);
}
};
}
/**
* Get the root page.
*
* @return the root page
*/
public Page getRoot() {
return root;
}
/**
* Get the map name.
*
* @return the name
*/
String getName() {
return name;
}
MVStore getStore() {
return store;
}
int getId() {
return id;
}
/**
* Rollback to the given version.
*
* @param version the version
*/
void rollbackTo(long version) {
checkWrite();
removeUnusedOldVersions();
if (version <= createVersion) {
removeMap();
} else if (root.getVersion() >= version) {
// iterating in descending order -
// this is not terribly efficient if there are many versions
ArrayList<Page> list = oldRoots;
while (list.size() > 0) {
int i = list.size() - 1;
Page p = list.get(i);
root = p;
list.remove(i);
if (p.getVersion() < version) {
break;
}
}
}
}
/**
* Forget all old versions.
*/
void removeAllOldVersions() {
// create a new instance
// because another thread might iterate over it
oldRoots = new ArrayList<Page>();
}
/**
* Forget those old versions that are no longer needed.
*/
void removeUnusedOldVersions() {
long oldest = store.getRetainVersion();
if (oldest == -1) {
return;
}
int i = searchRoot(oldest);
if (i < 0) {
return;
}
// create a new instance
// because another thread might iterate over it
ArrayList<Page> list = new ArrayList<Page>();
list.addAll(oldRoots.subList(i, oldRoots.size()));
oldRoots = list;
}
public void setReadOnly(boolean readOnly) {
this.readOnly = readOnly;
}
public boolean isReadOnly() {
return readOnly;
}
/**
* Check whether the map is open.
*
* @throws IllegalStateException if the map is closed
*/
protected void checkOpen() {
if (closed) {
throw new IllegalStateException("This map is closed");
}
}
/**
* Check whether writing is allowed.
*
* @throws IllegalStateException if the map is read-only
*/
protected void checkWrite() {
if (readOnly) {
checkOpen();
throw new IllegalStateException("This map is read-only");
}
}
public int hashCode() {
return id;
}
public boolean equals(Object o) {
return this == o;
}
public int size() {
long size = getSize();
return size > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int) size;
}
public long getSize() {
return root.getTotalCount();
}
long getCreateVersion() {
return createVersion;
}
/**
* Remove the given page (make the space available).
*
* @param p the page
*/
protected void removePage(Page p) {
store.removePage(p.getPos());
}
/**
* Open an old version for the given map.
*
* @param version the version
* @return the map
*/
public MVMap<K, V> openVersion(long version) {
if (readOnly) {
throw new IllegalArgumentException("This map is read-only - need to call the method on the writable map");
}
if (version < createVersion) {
throw new IllegalArgumentException("Unknown version");
}
Page newest = null;
// need to copy because it can change
Page r = root;
if (r.getVersion() == version) {
newest = r;
} else {
// find the newest page that has a getVersion() <= version
int i = searchRoot(version);
if (i < 0) {
// not found
if (i == -1) {
// smaller than all in-memory versions
return store.openMapVersion(version, name, this);
}
i = -i - 2;
}
newest = oldRoots.get(i);
}
MVMap<K, V> m = openReadOnly();
m.root = newest;
return m;
}
/**
* Open a copy of the map in read-only mode.
*
* @return the opened map
*/
protected MVMap<K, V> openReadOnly() {
MVMap<K, V> m = new MVMap<K, V>(keyType, valueType);
m.readOnly = true;
HashMap<String, String> config = New.hashMap();
config.put("id", String.valueOf(id));
config.put("name", name);
config.put("createVersion", String.valueOf(createVersion));
m.open(store, config);
m.root = root;
return m;
}
private int searchRoot(long version) {
int low = 0, high = oldRoots.size() - 1;
while (low <= high) {
int x = (low + high) >>> 1;
long v = oldRoots.get(x).getVersion();
if (v < version) {
low = x + 1;
} else if (version < v) {
high = x - 1;
} else {
return x;
}
}
return -(low + 1);
}
public long getVersion() {
return root.getVersion();
}
/**
* Get the child page count for this page. This is to allow another map
* implementation to override the default, in case the last child is not to
* be used.
*
* @param p the page
* @return the number of direct children
*/
protected int getChildPageCount(Page p) {
return p.getChildPageCount();
}
/**
* Get the map type. When opening an existing map, the map type must match.
*
* @return the map type
*/
public String getType() {
return "btree";
}
/**
* Get the map metadata as a string.
*
* @return the string
*/
public String asString() {
StringBuilder buff = new StringBuilder();
DataUtils.appendMap(buff, "id", id);
DataUtils.appendMap(buff, "name", name);
DataUtils.appendMap(buff, "type", getType());
DataUtils.appendMap(buff, "createVersion", createVersion);
if (keyType != null) {
DataUtils.appendMap(buff, "key", keyType.asString());
}
if (valueType != null) {
DataUtils.appendMap(buff, "value", valueType.asString());
}
return buff.toString();
}
}
h2/src/tools/org/h2/dev/store/btree/MVStoreBuilder.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
import java.util.HashMap;
import org.h2.dev.store.type.DataTypeFactory;
import org.h2.util.New;
/**
* A builder for an MVStore.
*/
public class MVStoreBuilder {
private final HashMap<String, Object> config = New.hashMap();
/**
* Use the following file name. If the file does not exist, it is
* automatically created.
*
* @param fileName the file name
* @return this
*/
public static MVStoreBuilder fileBased(String fileName) {
return new MVStoreBuilder().fileName(fileName);
}
/**
* Open the store in-memory. In this case, no data may be saved.
*
* @return the store
*/
public static MVStoreBuilder inMemory() {
return new MVStoreBuilder();
}
private MVStoreBuilder set(String key, Object value) {
if (config.containsKey(key)) {
throw new IllegalArgumentException("Parameter " + config.get(key) + " is already set");
}
config.put(key, value);
return this;
}
private MVStoreBuilder fileName(String fileName) {
return set("fileName", fileName);
}
/**
* Open the file in read-only mode. In this case, a shared lock will be
* acquired to ensure the file is not concurrently opened in write mode.
* <p>
* If this option is not used, the file is locked exclusively.
* <p>
* Please note a store may only be opened once in every JVM (no matter
* whether it is opened in read-only or read-write mode), because each file
* may be locked only once in a process.
*
* @return this
*/
public MVStoreBuilder readOnly() {
return set("openMode", "r");
}
/**
* Set the read cache size in MB. The default is 16 MB.
*
* @param mb the cache size
* @return this
*/
public MVStoreBuilder cacheSizeMB(int mb) {
return set("cacheSize", Integer.toString(mb));
}
/**
* Use the given data type factory.
*
* @param factory the data type factory
* @return this
*/
public MVStoreBuilder with(DataTypeFactory factory) {
return set("dataTypeFactory", factory);
}
/**
* Open the store.
*
* @return the opened store
*/
public MVStore open() {
MVStore s = new MVStore(config);
s.open();
return s;
}
public String toString() {
return DataUtils.appendMap(new StringBuilder(), config).toString();
}
/**
* Read the configuration from a string.
*
* @param s the string representation
* @return the builder
*/
public static MVStoreBuilder fromString(String s) {
HashMap<String, String> config = DataUtils.parseMap(s);
MVStoreBuilder builder = new MVStoreBuilder();
builder.config.putAll(config);
return builder;
}
}
h2/src/tools/org/h2/dev/store/btree/MVStoreTool.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringReader;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.Properties;
import org.h2.store.fs.FilePath;
import org.h2.store.fs.FileUtils;
/**
* Utility methods used in combination with the MVStore.
*/
public class MVStoreTool {
/**
* Runs this tool.
* Options are case sensitive. Supported options are:
* <table>
* <tr><td>[-dump &lt;dir&gt;]</td>
* <td>Dump the contends of the file</td></tr>
* </table>
*
* @param args the command line arguments
*/
public static void main(String... args) throws IOException {
for (int i = 0; i < args.length; i++) {
if ("-dump".equals(args[i])) {
String fileName = args[++i];
dump(fileName, new PrintWriter(System.out));
}
}
}
/**
* Read the contents of the file and display them in a human-readable
* format.
*
* @param fileName the name of the file
* @param writer the print writer
*/
public static void dump(String fileName, PrintWriter writer) throws IOException {
if (!FileUtils.exists(fileName)) {
writer.println("File not found: " + fileName);
return;
}
FileChannel file = null;
int blockSize = MVStore.BLOCK_SIZE;
try {
file = FilePath.get(fileName).open("r");
long fileLength = file.size();
byte[] header = new byte[blockSize];
file.read(ByteBuffer.wrap(header), 0);
Properties prop = new Properties();
prop.load(new ByteArrayInputStream(header));
prop.load(new StringReader(new String(header, "UTF-8")));
writer.println("file " + fileName);
writer.println(" length " + fileLength);
writer.println(" " + prop);
ByteBuffer block = ByteBuffer.allocate(40);
for (long pos = 0; pos < fileLength;) {
block.rewind();
DataUtils.readFully(file, pos, block);
block.rewind();
if (block.get() != 'c') {
pos += blockSize;
continue;
}
int chunkLength = block.getInt();
int chunkId = block.getInt();
int pageCount = block.getInt();
long metaRootPos = block.getLong();
long maxLength = block.getLong();
long maxLengthLive = block.getLong();
writer.println(" chunk " + chunkId +
" at " + pos +
" length " + chunkLength +
" pageCount " + pageCount +
" root " + metaRootPos +
" maxLength " + maxLength +
" maxLengthLive " + maxLengthLive);
ByteBuffer chunk = ByteBuffer.allocate(chunkLength);
DataUtils.readFully(file, pos, chunk);
int p = block.position();
pos = (pos + chunkLength + blockSize) / blockSize * blockSize;
chunkLength -= p;
while (chunkLength > 0) {
chunk.position(p);
int pageLength = chunk.getInt();
// check value (ignored)
chunk.getShort();
long mapId = DataUtils.readVarInt(chunk);
int len = DataUtils.readVarInt(chunk);
int type = chunk.get();
boolean compressed = (type & 2) != 0;
boolean node = (type & 1) != 0;
writer.println(" map " + mapId + " at " + p + " " +
(node ? "node" : "leaf") + " " +
(compressed ? "compressed " : "") +
"len: " + pageLength + " entries: " + len);
p += pageLength;
chunkLength -= pageLength;
}
}
} catch (IOException e) {
writer.println("ERROR: " + e);
throw e;
} finally {
if (file != null) {
try {
file.close();
} catch (IOException e) {
// ignore
}
}
}
writer.println();
writer.flush();
}
}
h2/src/tools/org/h2/dev/store/btree/Page.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.Arrays;
import org.h2.compress.Compressor;
import org.h2.dev.store.type.DataType;
/**
* A page (a node or a leaf).
* <p>
* For b-tree nodes, the key at a given index is larger than the largest key of
* the child at the same index.
* <p>
* File format:
* page length (including length): int
* check value: short
* map id: varInt
* number of keys: varInt
* type: byte (0: leaf, 1: node; +2: compressed)
* compressed: bytes saved (varInt)
* keys
* leaf: values (one for each key)
* node: children (1 more than keys)
*/
public class Page {
private static final int SHARED_KEYS = 1, SHARED_VALUES = 2, SHARED_CHILDREN = 4, SHARED_COUNTS = 8;
private static final Object[] EMPTY_OBJECT_ARRAY = new Object[0];
private final MVMap<?, ?> map;
private final long version;
private long pos;
private long totalCount;
private int keyCount;
/**
* The last result of a find operation is cached.
*/
private int cachedCompare;
/**
* Which arrays are shared with another version of this page.
*/
private int sharedFlags;
/**
* The estimated memory used.
*/
private int memory;
private Object[] keys;
private Object[] values;
private long[] children;
private Page[] childrenPages;
private long[] counts;
Page(MVMap<?, ?> map, long version) {
this.map = map;
this.version = version;
}
/**
* Create a new, empty page.
*
* @param map the map
* @param version the version
* @return the new page
*/
public static Page createEmpty(MVMap<?, ?> map, long version) {
return create(map, version, 0,
EMPTY_OBJECT_ARRAY, EMPTY_OBJECT_ARRAY,
null, null, null, 0, 0, DataUtils.PAGE_MEMORY);
}
/**
* Create a new page. The arrays are not cloned.
*
* @param map the map
* @param version the version
* @param keyCount the number of keys
* @param keys the keys
* @param values the values
* @param children the children
* @param childrenPages the children pages
* @param counts the children counts
* @param totalCount the total number of keys
* @param sharedFlags which arrays are shared
* @param memory the memory used in bytes
* @return the page
*/
public static Page create(MVMap<?, ?> map, long version,
int keyCount, Object[] keys,
Object[] values, long[] children, Page[] childrenPages, long[] counts,
long totalCount, int sharedFlags, int memory) {
Page p = new Page(map, version);
// the position is 0
p.keys = keys;
p.keyCount = keyCount;
p.values = values;
p.children = children;
p.childrenPages = childrenPages;
p.counts = counts;
p.totalCount = totalCount;
p.sharedFlags = sharedFlags;
p.memory = memory == 0 ? p.calculateMemory() : memory;
return p;
}
/**
* Read a page.
*
* @param file the file
* @param map the map
* @param pos the page position
* @param filePos the position in the file
* @param fileSize the file size (to avoid reading past EOF)
* @return the page
*/
static Page read(FileChannel file, MVMap<?, ?> map,
long pos, long filePos, long fileSize) {
ByteBuffer buff;
int maxLength = DataUtils.getPageMaxLength(pos);
try {
maxLength = (int) Math.min(fileSize - filePos, maxLength);
int length = maxLength;
if (maxLength == Integer.MAX_VALUE) {
buff = ByteBuffer.allocate(128);
DataUtils.readFully(file, filePos, buff);
maxLength = buff.getInt();
//read the first bytes again
}
buff = ByteBuffer.allocate(length);
DataUtils.readFully(file, filePos, buff);
} catch (IOException e) {
throw new RuntimeException(e);
}
Page p = new Page(map, 0);
p.pos = pos;
int chunkId = DataUtils.getPageChunkId(pos);
int offset = DataUtils.getPageOffset(pos);
p.read(buff, chunkId, offset, maxLength);
return p;
}
/**
* Get the key at the given index.
*
* @param index the index
* @return the key
*/
public Object getKey(int index) {
return keys[index];
}
/**
* Get the child page at the given index.
*
* @param index the index
* @return the child page
*/
public Page getChildPage(int index) {
Page p = childrenPages[index];
return p != null ? p : map.readPage(children[index]);
}
/**
* Get the position of the child page at the given index.
*
* @param index the index
* @return the position
*/
long getChildPagePos(int index) {
return children[index];
}
/**
* Get the value at the given index.
*
* @param index the index
* @return the value
*/
public Object getValue(int index) {
return values[index];
}
/**
* Get the number of keys in this page.
*
* @return the number of keys
*/
public int getKeyCount() {
return keyCount;
}
/**
* Check whether this is a leaf page.
*
* @return true if it is a leaf
*/
public boolean isLeaf() {
return children == null;
}
/**
* Get the position of the page
*
* @return the position
*/
public long getPos() {
return pos;
}
public String toString() {
StringBuilder buff = new StringBuilder();
buff.append("pos: ").append(pos).append("\n");
for (int i = 0; i <= keyCount; i++) {
if (i > 0) {
buff.append(" ");
}
if (children != null) {
buff.append("[" + children[i] + "] ");
}
if (i < keyCount) {
buff.append(keys[i]);
if (values != null) {
buff.append(':');
buff.append(values[i]);
}
}
}
return buff.toString();
}
/**
* Create a copy of this page, if the write version is higher than the
* current version.
*
* @param writeVersion the write version
* @return a page with the given write version
*/
public Page copyOnWrite(long writeVersion) {
if (version == writeVersion) {
return this;
}
map.getStore().removePage(pos);
Page newPage = create(map, writeVersion,
keyCount, keys, values, children, childrenPages,
counts, totalCount,
SHARED_KEYS | SHARED_VALUES | SHARED_CHILDREN | SHARED_COUNTS,
memory);
map.getStore().registerUnsavedPage();
newPage.cachedCompare = cachedCompare;
return newPage;
}
/**
* Search the key in this page using a binary search. Instead of always
* starting the search in the middle, the last found index is cached.
* <p>
* If the key was found, the returned value is the index in the key array.
* If not found, the returned value is negative, where -1 means the provided
* key is smaller than any keys in this page. See also Arrays.binarySearch.
*
* @param key the key
* @return the value or null
*/
public int binarySearch(Object key) {
int low = 0, high = keyCount - 1;
int x = cachedCompare - 1;
if (x < 0 || x > high) {
x = (low + high) >>> 1;
}
Object[] k = keys;
while (low <= high) {
int compare = map.compare(key, k[x]);
if (compare > 0) {
low = x + 1;
} else if (compare < 0) {
high = x - 1;
} else {
cachedCompare = x + 1;
return x;
}
x = (low + high) >>> 1;
}
cachedCompare = low;
return -(low + 1);
// regular binary search (without caching)
// int low = 0, high = keyCount - 1;
// while (low <= high) {
// int x = (low + high) >>> 1;
// int compare = map.compare(key, keys[x]);
// if (compare > 0) {
// low = x + 1;
// } else if (compare < 0) {
// high = x - 1;
// } else {
// return x;
// }
// }
// return -(low + 1);
}
/**
* Split the page. This modifies the current page.
*
* @param at the split index
* @return the page with the entries after the split index
*/
public Page split(int at) {
return isLeaf() ? splitLeaf(at) : splitNode(at);
}
private Page splitLeaf(int at) {
int a = at, b = keyCount - a;
Object[] aKeys = new Object[a];
Object[] bKeys = new Object[b];
System.arraycopy(keys, 0, aKeys, 0, a);
System.arraycopy(keys, a, bKeys, 0, b);
keys = aKeys;
keyCount = a;
Object[] aValues = new Object[a];
Object[] bValues = new Object[b];
bValues = new Object[b];
System.arraycopy(values, 0, aValues, 0, a);
System.arraycopy(values, a, bValues, 0, b);
values = aValues;
sharedFlags &= ~(SHARED_KEYS | SHARED_VALUES);
totalCount = a;
Page newPage = create(map, version, b,
bKeys, bValues, null, null, null,
bKeys.length, 0, 0);
map.getStore().registerUnsavedPage();
memory = calculateMemory();
newPage.memory = newPage.calculateMemory();
return newPage;
}
private Page splitNode(int at) {
int a = at, b = keyCount - a;
Object[] aKeys = new Object[a];
Object[] bKeys = new Object[b - 1];
System.arraycopy(keys, 0, aKeys, 0, a);
System.arraycopy(keys, a + 1, bKeys, 0, b - 1);
keys = aKeys;
keyCount = a;
long[] aChildren = new long[a + 1];
long[] bChildren = new long[b];
System.arraycopy(children, 0, aChildren, 0, a + 1);
System.arraycopy(children, a + 1, bChildren, 0, b);
children = aChildren;
Page[] aChildrenPages = new Page[a + 1];
Page[] bChildrenPages = new Page[b];
System.arraycopy(childrenPages, 0, aChildrenPages, 0, a + 1);
System.arraycopy(childrenPages, a + 1, bChildrenPages, 0, b);
childrenPages = aChildrenPages;
long[] aCounts = new long[a + 1];
long[] bCounts = new long[b];
System.arraycopy(counts, 0, aCounts, 0, a + 1);
System.arraycopy(counts, a + 1, bCounts, 0, b);
counts = aCounts;
sharedFlags &= ~(SHARED_KEYS | SHARED_CHILDREN | SHARED_COUNTS);
long t = 0;
for (long x : aCounts) {
t += x;
}
totalCount = t;
t = 0;
for (long x : bCounts) {
t += x;
}
Page newPage = create(map, version, b - 1,
bKeys, null, bChildren, bChildrenPages,
bCounts, t, 0, 0);
map.getStore().registerUnsavedPage();
memory = calculateMemory();
newPage.memory = newPage.calculateMemory();
return newPage;
}
/**
* Get the total number of key-value pairs, including child pages.
*
* @return the number of key-value pairs
*/
public long getTotalCount() {
if (MVStore.ASSERT) {
long check = 0;
if (isLeaf()) {
check = keyCount;
} else {
for (long x : counts) {
check += x;
}
}
if (check != totalCount) {
throw new AssertionError("Expected: " + check + " got: "
+ totalCount);
}
}
return totalCount;
}
/**
* Get the descendant counts for the given child.
*
* @param index the child index
* @return the descendant count
*/
long getCounts(int index) {
return counts[index];
}
/**
* Replace the child page.
*
* @param index the index
* @param c the new child page
*/
public void setChild(int index, Page c) {
if (c != childrenPages[index] || c.getPos() != children[index]) {
if ((sharedFlags & SHARED_CHILDREN) != 0) {
children = Arrays.copyOf(children, children.length);
childrenPages = Arrays.copyOf(childrenPages, childrenPages.length);
sharedFlags &= ~SHARED_CHILDREN;
}
children[index] = c.getPos();
childrenPages[index] = c;
}
if (c.getTotalCount() != counts[index]) {
if ((sharedFlags & SHARED_COUNTS) != 0) {
counts = Arrays.copyOf(counts, counts.length);
sharedFlags &= ~SHARED_COUNTS;
}
long oldCount = counts[index];
counts[index] = c.getTotalCount();
totalCount += counts[index] - oldCount;
}
}
/**
* Replace the key.
*
* @param index the index
* @param key the new key
*/
public void setKey(int index, Object key) {
if ((sharedFlags & SHARED_KEYS) != 0) {
keys = Arrays.copyOf(keys, keys.length);
sharedFlags &= ~SHARED_KEYS;
}
Object old = keys[index];
if (old != null) {
memory -= map.getKeyType().getMemory(old);
}
memory += map.getKeyType().getMemory(key);
keys[index] = key;
}
/**
* Replace the value.
*
* @param index the index
* @param value the new value
* @return the old value
*/
public Object setValue(int index, Object value) {
Object old = values[index];
if ((sharedFlags & SHARED_VALUES) != 0) {
values = Arrays.copyOf(values, values.length);
sharedFlags &= ~SHARED_VALUES;
}
memory -= map.getValueType().getMemory(old);
memory += map.getValueType().getMemory(value);
values[index] = value;
return old;
}
/**
* Remove this page and all child pages.
*/
void removeAllRecursive() {
if (children != null) {
for (int i = 0, size = children.length; i < size; i++) {
Page p = childrenPages[i];
if (p != null) {
p.removeAllRecursive();
} else {
long c = children[i];
int type = DataUtils.getPageType(c);
if (type == DataUtils.PAGE_TYPE_LEAF) {
map.getStore().removePage(c);
} else {
map.readPage(c).removeAllRecursive();
}
}
}
}
map.getStore().removePage(pos);
}
/**
* Insert a key-value pair into this leaf.
*
* @param index the index
* @param key the key
* @param value the value
*/
public void insertLeaf(int index, Object key, Object value) {
if (((sharedFlags & SHARED_KEYS) == 0) && keys.length > keyCount + 1) {
if (index < keyCount) {
System.arraycopy(keys, index, keys, index + 1, keyCount - index);
System.arraycopy(values, index, values, index + 1, keyCount - index);
}
} else {
int len = keyCount + 6;
Object[] newKeys = new Object[len];
DataUtils.copyWithGap(keys, newKeys, keyCount, index);
keys = newKeys;
Object[] newValues = new Object[len];
DataUtils.copyWithGap(values, newValues, keyCount, index);
values = newValues;
}
keys[index] = key;
values[index] = value;
keyCount++;
sharedFlags &= ~(SHARED_KEYS | SHARED_VALUES);
totalCount++;
memory += map.getKeyType().getMemory(key);
memory += map.getValueType().getMemory(value);
}
/**
* Insert a child into this node.
*
* @param index the index
* @param key the key
* @param childPage the child page
*/
public void insertNode(int index, Object key, Page childPage) {
Object[] newKeys = new Object[keyCount + 1];
DataUtils.copyWithGap(keys, newKeys, keyCount, index);
newKeys[index] = key;
keys = newKeys;
keyCount++;
long[] newChildren = new long[children.length + 1];
DataUtils.copyWithGap(children, newChildren, children.length, index);
newChildren[index] = childPage.getPos();
children = newChildren;
Page[] newChildrenPages = new Page[childrenPages.length + 1];
DataUtils.copyWithGap(childrenPages, newChildrenPages, childrenPages.length, index);
newChildrenPages[index] = childPage;
childrenPages = newChildrenPages;
long[] newCounts = new long[counts.length + 1];
DataUtils.copyWithGap(counts, newCounts, counts.length, index);
newCounts[index] = childPage.getTotalCount();
counts = newCounts;
sharedFlags &= ~(SHARED_KEYS | SHARED_CHILDREN | SHARED_COUNTS);
totalCount += childPage.getTotalCount();
memory += map.getKeyType().getMemory(key);
memory += DataUtils.PAGE_MEMORY_CHILD;
}
/**
* Remove the key and value (or child) at the given index.
*
* @param index the index
*/
public void remove(int index) {
int keyIndex = index >= keyCount ? index - 1 : index;
Object old = keys[keyIndex];
memory -= map.getKeyType().getMemory(old);
if ((sharedFlags & SHARED_KEYS) == 0 && keys.length > keyCount - 4) {
if (keyIndex < keyCount - 1) {
System.arraycopy(keys, keyIndex + 1, keys, keyIndex, keyCount - keyIndex - 1);
}
keys[keyCount - 1] = null;
} else {
Object[] newKeys = new Object[keyCount - 1];
DataUtils.copyExcept(keys, newKeys, keyCount, keyIndex);
keys = newKeys;
sharedFlags &= ~SHARED_KEYS;
}
if (values != null) {
old = values[index];
memory -= map.getValueType().getMemory(old);
if ((sharedFlags & SHARED_VALUES) == 0 && values.length > keyCount - 4) {
if (index < keyCount - 1) {
System.arraycopy(values, index + 1, values, index, keyCount - index - 1);
}
values[keyCount - 1] = null;
} else {
Object[] newValues = new Object[keyCount - 1];
DataUtils.copyExcept(values, newValues, keyCount, index);
values = newValues;
sharedFlags &= ~SHARED_VALUES;
}
totalCount--;
}
keyCount--;
if (children != null) {
memory -= DataUtils.PAGE_MEMORY_CHILD;
long countOffset = counts[index];
long[] newChildren = new long[children.length - 1];
DataUtils.copyExcept(children, newChildren, children.length, index);
children = newChildren;
Page[] newChildrenPages = new Page[childrenPages.length - 1];
DataUtils.copyExcept(childrenPages, newChildrenPages,
childrenPages.length, index);
childrenPages = newChildrenPages;
long[] newCounts = new long[counts.length - 1];
DataUtils.copyExcept(counts, newCounts, counts.length, index);
counts = newCounts;
sharedFlags &= ~(SHARED_CHILDREN | SHARED_COUNTS);
totalCount -= countOffset;
}
}
/**
* Read the page from the buffer.
*
* @param buff the buffer
* @param chunkId the chunk id
* @param offset the offset within the chunk
* @param maxLength the maximum length
*/
void read(ByteBuffer buff, int chunkId, int offset, int maxLength) {
int start = buff.position();
int pageLength = buff.getInt();
if (pageLength > maxLength) {
throw new RuntimeException("Length too large, expected =< "
+ maxLength + " got " + pageLength);
}
short check = buff.getShort();
int mapId = DataUtils.readVarInt(buff);
if (mapId != map.getId()) {
throw new RuntimeException("Error reading page, expected map "
+ map.getId() + " got " + mapId);
}
int checkTest = DataUtils.getCheckValue(chunkId)
^ DataUtils.getCheckValue(offset)
^ DataUtils.getCheckValue(pageLength);
if (check != (short) checkTest) {
throw new RuntimeException("Error in check value, expected "
+ checkTest + " got " + check);
}
int len = DataUtils.readVarInt(buff);
keys = new Object[len];
keyCount = len;
int type = buff.get();
boolean node = (type & 1) == DataUtils.PAGE_TYPE_NODE;
boolean compressed = (type & DataUtils.PAGE_COMPRESSED) != 0;
if (compressed) {
Compressor compressor = map.getStore().getCompressor();
int lenAdd = DataUtils.readVarInt(buff);
int compLen = pageLength + start - buff.position();
byte[] comp = new byte[compLen];
buff.get(comp);
int l = compLen + lenAdd;
buff = ByteBuffer.allocate(l);
compressor.expand(comp, 0, compLen, buff.array(), 0, l);
}
DataType keyType = map.getKeyType();
for (int i = 0; i < len; i++) {
Object k = keyType.read(buff);
keys[i] = k;
}
if (node) {
children = new long[len + 1];
for (int i = 0; i <= len; i++) {
children[i] = buff.getLong();
}
childrenPages = new Page[len + 1];
counts = new long[len + 1];
long total = 0;
for (int i = 0; i <= len; i++) {
long s = DataUtils.readVarLong(buff);
total += s;
counts[i] = s;
}
totalCount = total;
} else {
values = new Object[len];
DataType valueType = map.getValueType();
for (int i = 0; i < len; i++) {
Object v = valueType.read(buff);
values[i] = v;
}
totalCount = len;
}
memory = calculateMemory();
}
/**
* Store the page and update the position.
*
* @param chunk the chunk
* @param buff the target buffer
*/
private void write(Chunk chunk, ByteBuffer buff) {
int start = buff.position();
buff.putInt(0);
buff.putShort((byte) 0);
DataUtils.writeVarInt(buff, map.getId());
int len = keyCount;
DataUtils.writeVarInt(buff, len);
Compressor compressor = map.getStore().getCompressor();
int type = children != null ? DataUtils.PAGE_TYPE_NODE
: DataUtils.PAGE_TYPE_LEAF;
buff.put((byte) type);
int compressStart = buff.position();
for (int i = 0; i < len; i++) {
map.getKeyType().write(buff, keys[i]);
}
if (type == DataUtils.PAGE_TYPE_NODE) {
for (int i = 0; i <= len; i++) {
buff.putLong(children[i]);
}
for (int i = 0; i <= len; i++) {
DataUtils.writeVarLong(buff, counts[i]);
}
} else {
for (int i = 0; i < len; i++) {
map.getValueType().write(buff, values[i]);
}
}
if (compressor != null) {
int expLen = buff.position() - compressStart;
byte[] exp = new byte[expLen];
buff.position(compressStart);
buff.get(exp);
byte[] comp = new byte[exp.length * 2];
int compLen = compressor.compress(exp, exp.length, comp, 0);
if (compLen + DataUtils.getVarIntLen(compLen - expLen) < expLen) {
buff.position(compressStart - 1);
buff.put((byte) (type + DataUtils.PAGE_COMPRESSED));
DataUtils.writeVarInt(buff, expLen - compLen);
buff.put(comp, 0, compLen);
}
}
int pageLength = buff.position() - start;
buff.putInt(start, pageLength);
int chunkId = chunk.id;
int check = DataUtils.getCheckValue(chunkId)
^ DataUtils.getCheckValue(start)
^ DataUtils.getCheckValue(pageLength);
buff.putShort(start + 4, (short) check);
this.pos = DataUtils.getPagePos(chunkId, start, pageLength, type);
long max = DataUtils.getPageMaxLength(pos);
chunk.maxLength += max;
chunk.maxLengthLive += max;
chunk.pageCount++;
}
/**
* Get the maximum length in bytes to store temporary records, recursively.
*
* @return the maximum length
*/
int getMaxLengthTempRecursive() {
int maxLength = getMaxLength();
if (!isLeaf()) {
for (int i = 0; i <= keyCount; i++) {
Page p = childrenPages[i];
if (p != null) {
maxLength += p.getMaxLengthTempRecursive();
}
}
}
return maxLength;
}
int getMaxLength() {
// length, check, map id, key length, type
int maxLength = 4 + 2 + DataUtils.MAX_VAR_INT_LEN
+ DataUtils.MAX_VAR_INT_LEN + 1;
int len = keyCount;
for (int i = 0; i < len; i++) {
maxLength += map.getKeyType().getMaxLength(keys[i]);
}
if (isLeaf()) {
for (int i = 0; i < len; i++) {
maxLength += map.getValueType().getMaxLength(values[i]);
}
} else {
maxLength += 8 * len;
maxLength += DataUtils.MAX_VAR_LONG_LEN * len;
}
return maxLength;
}
/**
* Store this page and all children that are changed, in reverse order, and
* update the position and the children.
*
* @param chunk the chunk
* @param buff the target buffer
* @return the page id
*/
long writeUnsavedRecursive(Chunk chunk, ByteBuffer buff) {
if (!isLeaf()) {
int len = children.length;
for (int i = 0; i < len; i++) {
Page p = childrenPages[i];
if (p != null) {
children[i] = p.writeUnsavedRecursive(chunk, buff);
childrenPages[i] = null;
}
}
}
write(chunk, buff);
return pos;
}
long getVersion() {
return version;
}
public int getChildPageCount() {
return children.length;
}
public boolean equals(Object other) {
if (other == this) {
return true;
}
if (other instanceof Page) {
if (pos != 0 && ((Page) other).pos == pos) {
return true;
}
return this == other;
}
return false;
}
public int hashCode() {
return pos != 0 ? (int) (pos | (pos >>> 32)) : super.hashCode();
}
public int getMemory() {
if (MVStore.ASSERT) {
if (memory != calculateMemory()) {
throw new RuntimeException("Memory calculation error");
}
}
return memory;
}
private int calculateMemory() {
int mem = DataUtils.PAGE_MEMORY;
for (int i = 0; i < keyCount; i++) {
mem += map.getKeyType().getMemory(keys[i]);
}
if (this.isLeaf()) {
for (int i = 0; i < keyCount; i++) {
mem += map.getValueType().getMemory(values[i]);
}
} else {
mem += this.getChildPageCount() * DataUtils.PAGE_MEMORY_CHILD;
}
return mem;
}
}
h2/src/tools/org/h2/dev/store/btree/StreamStore.java deleted 100644 → 0
浏览文件 @ b222ae75
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.dev.store.btree;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.util.Map;
import java.util.concurrent.atomic.AtomicLong;
import org.h2.util.IOUtils;
/**
* A facility to store streams in a map. Streams are split into blocks, which
* are stored in a map. Very small streams are inlined in the stream id.
* <p>
* The key of the map is a long (incremented for each stored block). The default
* initial value is 0. Before storing blocks into the map, the stream store
* checks if there is already a block with the next key, and if necessary
* searches the next free entry using a binary search (0 to Long.MAX_VALUE).
* <p>
* The format of the binary id is: An empty id represents 0 bytes of data.
* In-place data is encoded as 0, the size (a variable size int), then the data.
* A stored block is encoded as 1, the length of the block (a variable size
* int), then the key (a variable size long). Multiple ids can be concatenated
* to concatenate the data. If the id is large, it is stored itself, which is
* encoded as 2, the total length (a variable size long), and the key of the
* block that contains the id (a variable size long).
*/
public class StreamStore {
private final Map<Long, byte[]> map;
private int minBlockSize = 256;
private int maxBlockSize = 256 * 1024;
private final AtomicLong nextKey = new AtomicLong();
/**
* Create a stream store instance.
*
* @param map the map to store blocks of data
*/
public StreamStore(Map<Long, byte[]> map) {
this.map = map;
}
public Map<Long, byte[]> getMap() {
return map;
}
public void setNextKey(long nextKey) {
this.nextKey.set(nextKey);
}
public long getNextKey() {
return nextKey.get();
}
public void setMinBlockSize(int minBlockSize) {
this.minBlockSize = minBlockSize;
}
public int getMinBlockSize() {
return minBlockSize;
}
public void setMaxBlockSize(int maxBlockSize) {
this.maxBlockSize = maxBlockSize;
}
public long getMaxBlockSize() {
return maxBlockSize;
}
/**
* Store the stream, and return the id.
*
* @param in the stream
* @return the id (potentially an empty array)
*/
public byte[] put(InputStream in) throws IOException {
ByteArrayOutputStream id = new ByteArrayOutputStream();
int level = 0;
while (true) {
if (put(id, in, level)) {
break;
}
if (id.size() > maxBlockSize / 2) {
id = putIndirectId(id);
level++;
}
}
if (id.size() > minBlockSize * 2) {
id = putIndirectId(id);
}
return id.toByteArray();
}
private boolean put(ByteArrayOutputStream id, InputStream in, int level) throws IOException {
if (level > 0) {
ByteArrayOutputStream id2 = new ByteArrayOutputStream();
while (true) {
boolean eof = put(id2, in, level - 1);
if (id2.size() > maxBlockSize / 2) {
id2 = putIndirectId(id2);
id2.writeTo(id);
return eof;
} else if (eof) {
id2.writeTo(id);
return true;
}
}
}
ByteArrayOutputStream buffer = new ByteArrayOutputStream();
int len = (int) IOUtils.copy(in, buffer, maxBlockSize);
if (len == 0) {
return true;
}
boolean eof = len < maxBlockSize;
byte[] data = buffer.toByteArray();
if (len < minBlockSize) {
id.write(0);
DataUtils.writeVarInt(id, len);
id.write(data);
} else {
id.write(1);
DataUtils.writeVarInt(id, len);
DataUtils.writeVarLong(id, writeBlock(data));
}
return eof;
}
private ByteArrayOutputStream putIndirectId(ByteArrayOutputStream id) throws IOException {
byte[] data = id.toByteArray();
id = new ByteArrayOutputStream();
id.write(2);
DataUtils.writeVarLong(id, length(data));
DataUtils.writeVarLong(id, writeBlock(data));
return id;
}
private long writeBlock(byte[] data) {
long key = getAndIncrementNextKey();
map.put(key, data);
return key;
}
private long getAndIncrementNextKey() {
long key = nextKey.getAndIncrement();
if (!map.containsKey(key)) {
return key;
}
// search the next free id using binary search
synchronized (this) {
long low = key, high = Long.MAX_VALUE;
while (low < high) {
long x = (low + high) >>> 1;
if (map.containsKey(x)) {
low = x + 1;
} else {
high = x;
}
}
key = low;
nextKey.set(key + 1);
return key;
}
}
/**
* Remove all stored blocks for the given id.
*
* @param id the id
*/
public void remove(byte[] id) {
ByteBuffer idBuffer = ByteBuffer.wrap(id);
while (idBuffer.hasRemaining()) {
switch (idBuffer.get()) {
case 0:
int len = DataUtils.readVarInt(idBuffer);
idBuffer.position(idBuffer.position() + len);
break;
case 1:
DataUtils.readVarInt(idBuffer);
long k = DataUtils.readVarLong(idBuffer);
map.remove(k);
break;
case 2:
DataUtils.readVarLong(idBuffer);
long k2 = DataUtils.readVarLong(idBuffer);
// recurse
remove(map.get(k2));
map.remove(k2);
break;
default:
throw new IllegalArgumentException("Unsupported id");
}
}
}
/**
* Calculate the number of data bytes for the given id. As the length is
* encoded in the id, this operation does not cause any reads in the map.
*
* @param id the id
* @return the length
*/
public long length(byte[] id) {
ByteBuffer idBuffer = ByteBuffer.wrap(id);
long length = 0;
while (idBuffer.hasRemaining()) {
switch (idBuffer.get()) {
case 0:
int len = DataUtils.readVarInt(idBuffer);
idBuffer.position(idBuffer.position() + len);
length += len;
break;
case 1:
length += DataUtils.readVarInt(idBuffer);
DataUtils.readVarLong(idBuffer);
break;
case 2:
length += DataUtils.readVarLong(idBuffer);
DataUtils.readVarLong(idBuffer);
break;
default:
throw new IllegalArgumentException("Unsupported id");
}
}
return length;
}
/**
* Check whether the id itself contains all the data. This operation does
* not cause any reads in the map.
*
* @param id the id
* @return if the id contains the data
*/
public boolean isInPlace(byte[] id) {
ByteBuffer idBuffer = ByteBuffer.wrap(id);
while (idBuffer.hasRemaining()) {
if (idBuffer.get() != 0) {
return false;
}
int len = DataUtils.readVarInt(idBuffer);
idBuffer.position(idBuffer.position() + len);
}
return true;
}
/**
* Open an input stream to read data.
*
* @param id the id
* @return the stream
*/
public InputStream get(byte[] id) {
return new Stream(this, id);
}
/**
* Get the block.
*
* @param key the key
* @return the block
*/
byte[] getBlock(long key) {
return map.get(key);
}
/**
* A stream backed by a map.
*/
static class Stream extends InputStream {
private final StreamStore store;
private byte[] oneByteBuffer;
private ByteBuffer idBuffer;
private ByteArrayInputStream buffer;
private long skip;
private final long length;
private long pos;
Stream(StreamStore store, byte[] id) {
this.store = store;
this.length = store.length(id);
this.idBuffer = ByteBuffer.wrap(id);
}
@Override
public int read() {
byte[] buffer = oneByteBuffer;
if (buffer == null) {
buffer = oneByteBuffer = new byte[1];
}
int len = read(buffer, 0, 1);
return len == -1 ? -1 : (buffer[0] & 255);
}
@Override
public long skip(long n) {
n = Math.min(length - pos, n);
if (n == 0) {
return 0;
}
if (buffer != null) {
long s = buffer.skip(n);
if (s > 0) {
n = s;
} else {
buffer = null;
skip += n;
}
} else {
skip += n;
}
pos += n;
return n;
}
@Override
public void close() {
buffer = null;
idBuffer.position(idBuffer.limit());
pos = length;
}
@Override
public int read(byte[] b, int off, int len) {
while (true) {
if (buffer == null) {
buffer = nextBuffer();
if (buffer == null) {
return -1;
}
}
int result = buffer.read(b, off, len);
if (result > 0) {
pos += result;
return result;
}
buffer = null;
}
}
private ByteArrayInputStream nextBuffer() {
while (idBuffer.hasRemaining()) {
switch (idBuffer.get()) {
case 0: {
int len = DataUtils.readVarInt(idBuffer);
if (skip >= len) {
skip -= len;
idBuffer.position(idBuffer.position() + len);
continue;
}
int p = (int) (idBuffer.position() + skip);
int l = (int) (len - skip);
idBuffer.position(p + l);
return new ByteArrayInputStream(idBuffer.array(), p, l);
}
case 1: {
int len = DataUtils.readVarInt(idBuffer);
long key = DataUtils.readVarLong(idBuffer);
if (skip >= len) {
skip -= len;
continue;
}
byte[] data = store.getBlock(key);
int s = (int) skip;
skip = 0;
return new ByteArrayInputStream(data, s, data.length - s);
}
case 2: {
long len = DataUtils.readVarInt(idBuffer);
long key = DataUtils.readVarLong(idBuffer);
if (skip >= len) {
skip -= len;
continue;
}
byte[] k = store.getBlock(key);
ByteBuffer newBuffer = ByteBuffer.allocate(k.length + idBuffer.limit() - idBuffer.position());
newBuffer.put(k);
newBuffer.put(idBuffer);
newBuffer.flip();
idBuffer = newBuffer;
return nextBuffer();
}
default:
throw new IllegalArgumentException("Unsupported id");
}
}
return null;
}
}
}
h2/src/tools/org/h2/dev/store/btree/package.html deleted 100644 → 0
浏览文件 @ b222ae75
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<!--
Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License, Version 1.0,
and under the Eclipse Public License, Version 1.0
(http://h2database.com/html/license.html).
Initial Developer: H2 Group
-->
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head><meta http-equiv="Content-Type" content="text/html;charset=utf-8" /><title>
Javadoc package documentation
</title></head><body style="font: 9pt/130% Tahoma, Arial, Helvetica, sans-serif; font-weight: normal;"><p>
A persistent storage for tree maps.
</p></body></html>
\ No newline at end of file
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