Page store: refactor to support compacting

h2/src/main/org/h2/index/PageBtree.java

@@ -9,12 +9,17 @@ package org.h2.index;
 import java.sql.SQLException;
 import org.h2.result.SearchRow;
 import org.h2.store.Data;
-import org.h2.store.Record;
+import org.h2.store.Page;
 
 /**
  * A page that contains index data.
  */
-abstract class PageBtree extends Record {
+public abstract class PageBtree extends Page {
+
+    /**
+     * This is a root page.
+     */
+    static final int ROOT = 0;
 
     /**
      * Indicator that the row count is not known.
@@ -66,9 +71,8 @@ abstract class PageBtree extends Record {
      */
     protected boolean written;
 
-    PageBtree(PageBtreeIndex index, int pageId, int parentPageId, Data data) {
+    PageBtree(PageBtreeIndex index, int pageId, Data data) {
         this.index = index;
-        this.parentPageId = parentPageId;
         this.data = data;
         setPos(pageId);
     }
@@ -129,11 +133,6 @@ abstract class PageBtree extends Record {
         return l;
     }
 
-    /**
-     * Read the data.
-     */
-    abstract void read() throws SQLException;
-
     /**
      * Add a row if possible. If it is possible this method returns -1, otherwise
      * the split point. It is always possible to add one row.

h2/src/main/org/h2/index/PageBtreeIndex.java

@@ -16,7 +16,6 @@ import org.h2.result.SearchRow;
 import org.h2.store.Data;
 import org.h2.store.DataPage;
 import org.h2.store.PageStore;
-import org.h2.store.Record;
 import org.h2.table.Column;
 import org.h2.table.IndexColumn;
 import org.h2.table.TableData;
@@ -46,6 +45,7 @@ public class PageBtreeIndex extends BaseIndex {
             throw Message.throwInternalError("" + indexName);
         }
         this.store = database.getPageStore();
+        store.addIndex(this);
         if (headPos == Index.EMPTY_HEAD) {
             // new index
             needRebuild = true;
@@ -54,7 +54,8 @@ public class PageBtreeIndex extends BaseIndex {
             // it should not for new tables, otherwise redo of other operations
             // must ensure this page is not used for other things
             store.addMeta(this, session, headPos);
-            PageBtreeLeaf root = new PageBtreeLeaf(this, headPos, Page.ROOT, store.createData());
+            PageBtreeLeaf root = new PageBtreeLeaf(this, headPos, store.createData());
+            root.parentPageId = PageBtree.ROOT;
             store.updateRecord(root, true, root.data);
         } else {
             this.headPos = headPos;
@@ -101,7 +102,8 @@ public class PageBtreeIndex extends BaseIndex {
             page1.setPageId(id);
             page1.setParentPageId(headPos);
             page2.setParentPageId(headPos);
-            PageBtreeNode newRoot = new PageBtreeNode(this, rootPageId, Page.ROOT, store.createData());
+            PageBtreeNode newRoot = new PageBtreeNode(this, rootPageId, store.createData());
+            newRoot.parentPageId = PageBtree.ROOT;
             newRoot.init(page1, pivot, page2);
             store.updateRecord(page1, true, page1.data);
             store.updateRecord(page2, true, page2.data);
@@ -134,39 +136,13 @@ public class PageBtreeIndex extends BaseIndex {
      * @return the page
      */
     PageBtree getPage(int id) throws SQLException {
-        Record rec = store.getRecord(id);
-        if (rec != null) {
-            if (SysProperties.CHECK) {
-                if (!(rec instanceof PageBtree)) {
-                    throw Message.throwInternalError("Wrong page: " + rec + " " + this);
-                }
-                PageBtree result = (PageBtree) rec;
-                if (result.index.headPos != this.headPos) {
-                    throw Message.throwInternalError("Wrong index: " + result.index + " " + this);
-                }
-            }
-            return (PageBtree) rec;
-        }
-        Data data = store.readPage(id);
-        data.reset();
-        int parentPageId = data.readInt();
-        int type = data.readByte() & 255;
-        PageBtree result;
-        switch (type & ~Page.FLAG_LAST) {
-        case Page.TYPE_BTREE_LEAF:
-            result = new PageBtreeLeaf(this, id, parentPageId, data);
-            break;
-        case Page.TYPE_BTREE_NODE:
-            result = new PageBtreeNode(this, id, parentPageId, data);
-            break;
-        case Page.TYPE_EMPTY:
-            PageBtreeLeaf empty = new PageBtreeLeaf(this, id, parentPageId, data);
+        PageBtree p = (PageBtree) store.getPage(id);
+        if (p == null) {
+            Data data = store.createData();
+            PageBtreeLeaf empty = new PageBtreeLeaf(this, id, data);
             return empty;
-        default:
-            throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1, "page=" + id + " type=" + type);
         }
-        result.read();
-        return result;
+        return p;
     }
 
     public boolean canGetFirstOrLast() {
@@ -276,7 +252,8 @@ public class PageBtreeIndex extends BaseIndex {
     private void removeAllRows() throws SQLException {
         PageBtree root = getPage(headPos);
         root.freeChildren();
-        root = new PageBtreeLeaf(this, headPos, Page.ROOT, store.createData());
+        root = new PageBtreeLeaf(this, headPos, store.createData());
+        root.parentPageId = PageBtree.ROOT;
         store.removeRecord(headPos);
         store.updateRecord(root, true, null);
         rowCount = 0;

h2/src/main/org/h2/index/PageBtreeLeaf.java

@@ -13,37 +13,53 @@ import org.h2.message.Message;
 import org.h2.result.SearchRow;
 import org.h2.store.Data;
 import org.h2.store.DataPage;
+import org.h2.store.Page;
 
 /**
  * A b-tree leaf page that contains index data.
  * Format:
  * <ul><li>0-3: parent page id (0 for root)
  * </li><li>4-4: page type
- * </li><li>5-8: table id
+ * </li><li>5-8: index id
  * </li><li>9-10: entry count
  * </li><li>11-: list of key / offset pairs (4 bytes key, 2 bytes offset)
  * </li><li>data
  * </li></ul>
  */
-class PageBtreeLeaf extends PageBtree {
+public class PageBtreeLeaf extends PageBtree {
 
     private static final int OFFSET_LENGTH = 2;
     private static final int OFFSET_START = 11;
 
-    PageBtreeLeaf(PageBtreeIndex index, int pageId, int parentPageId, Data data) {
-        super(index, pageId, parentPageId, data);
+    PageBtreeLeaf(PageBtreeIndex index, int pageId, Data data) {
+        super(index, pageId, data);
         start = OFFSET_START;
     }
 
-    void read() throws SQLException {
-        data.setPos(4);
+    /**
+     * Read a b-tree leaf page.
+     *
+     * @param index the index
+     * @param data the data
+     * @param pageId the page id
+     * @return the page
+     */
+    public static Page read(PageBtreeIndex index, Data data, int pageId) throws SQLException {
+        PageBtreeLeaf p = new PageBtreeLeaf(index, pageId, data);
+        p.read();
+        return p;
+    }
+
+    private void read() throws SQLException {
+        data.reset();
+        this.parentPageId = data.readInt();
         int type = data.readByte();
         onlyPosition = (type & Page.FLAG_LAST) == 0;
-        int tableId = data.readInt();
-        if (tableId != index.getId()) {
+        int indexId = data.readInt();
+        if (indexId != index.getId()) {
             throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1,
-                    "page:" + getPos() + " expected table:" + index.getId() +
-                    "got:" + tableId);
+                    "page:" + getPos() + " expected index:" + index.getId() +
+                    "got:" + indexId);
         }
         entryCount = data.readShortInt();
         offsets = new int[entryCount];
@@ -137,7 +153,8 @@ class PageBtreeLeaf extends PageBtree {
 
     PageBtree split(int splitPoint) throws SQLException {
         int newPageId = index.getPageStore().allocatePage();
-        PageBtreeLeaf p2 = new PageBtreeLeaf(index, newPageId, parentPageId, index.getPageStore().createData());
+        PageBtreeLeaf p2 = new PageBtreeLeaf(index, newPageId, index.getPageStore().createData());
+        p2.parentPageId = parentPageId;
         for (int i = splitPoint; i < entryCount;) {
             p2.addRowTry(getRow(splitPoint));
             removeRow(splitPoint);
@@ -216,7 +233,7 @@ class PageBtreeLeaf extends PageBtree {
     void find(PageBtreeCursor cursor, SearchRow first, boolean bigger) throws SQLException {
         int i = find(first, bigger, false, false);
         if (i > entryCount) {
-            if (parentPageId == Page.ROOT) {
+            if (parentPageId == PageBtree.ROOT) {
                 return;
             }
             PageBtreeNode next = (PageBtreeNode) index.getPage(parentPageId);
@@ -240,7 +257,7 @@ class PageBtreeLeaf extends PageBtree {
      * @param cursor the cursor
      */
     void nextPage(PageBtreeCursor cursor) throws SQLException {
-        if (parentPageId == Page.ROOT) {
+        if (parentPageId == PageBtree.ROOT) {
             cursor.setCurrent(null, 0);
             return;
         }
@@ -254,7 +271,7 @@ class PageBtreeLeaf extends PageBtree {
      * @param cursor the cursor
      */
     void previousPage(PageBtreeCursor cursor) throws SQLException {
-        if (parentPageId == Page.ROOT) {
+        if (parentPageId == PageBtree.ROOT) {
             cursor.setCurrent(null, 0);
             return;
         }

h2/src/main/org/h2/index/PageBtreeNode.java

@@ -7,11 +7,13 @@
 package org.h2.index;
 
 import java.sql.SQLException;
+import org.h2.constant.ErrorCode;
 import org.h2.constant.SysProperties;
 import org.h2.message.Message;
 import org.h2.result.SearchRow;
 import org.h2.store.Data;
 import org.h2.store.DataPage;
+import org.h2.store.Page;
 import org.h2.store.PageStore;
 import org.h2.util.MemoryUtils;
 
@@ -21,18 +23,19 @@ import org.h2.util.MemoryUtils;
  * <ul>
  * <li>0-3: parent page id</li>
  * <li>4-4: page type</li>
- * <li>5-6: entry count</li>
- * <li>7-10: row count of all children (-1 if not known)</li>
- * <li>11-14: rightmost child page id</li>
- * <li>15- entries: 4 bytes leaf page id, 4 bytes offset to data</li>
+ * <li>5-8: index id</li>
+ * <li>9-10: entry count</li>
+ * <li>11-14: row count of all children (-1 if not known)</li>
+ * <li>15-18: rightmost child page id</li>
+ * <li>19- entries: 4 bytes leaf page id, 4 bytes offset to data</li>
  * </ul>
  * The row is the largest row of the respective child, meaning
  * row[0] is the largest row of child[0].
  */
-class PageBtreeNode extends PageBtree {
+public class PageBtreeNode extends PageBtree {
 
     private static final int CHILD_OFFSET_PAIR_LENGTH = 8;
-    private static final int CHILD_OFFSET_PAIR_START = 15;
+    private static final int CHILD_OFFSET_PAIR_START = 19;
 
     /**
      * The page ids of the children.
@@ -43,15 +46,36 @@ class PageBtreeNode extends PageBtree {
 
     private int rowCount = UNKNOWN_ROWCOUNT;
 
-    PageBtreeNode(PageBtreeIndex index, int pageId, int parentPageId, Data data) {
-        super(index, pageId, parentPageId, data);
+    PageBtreeNode(PageBtreeIndex index, int pageId, Data data) {
+        super(index, pageId, data);
         start = CHILD_OFFSET_PAIR_START;
     }
 
-    void read() {
-        data.setPos(4);
+    /**
+     * Read a b-tree node page.
+     *
+     * @param index the index
+     * @param data the data
+     * @param pageId the page id
+     * @return the page
+     */
+    public static Page read(PageBtreeIndex index, Data data, int pageId) throws SQLException {
+        PageBtreeNode p = new PageBtreeNode(index, pageId, data);
+        p.read();
+        return p;
+    }
+
+    private void read() throws SQLException {
+        data.reset();
+        this.parentPageId = data.readInt();
         int type = data.readByte();
         onlyPosition = (type & Page.FLAG_LAST) == 0;
+        int indexId = data.readInt();
+        if (indexId != index.getId()) {
+            throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1,
+                    "page:" + getPos() + " expected index:" + index.getId() +
+                    "got:" + indexId);
+        }
         entryCount = data.readShortInt();
         rowCount = data.readInt();
         if (!PageStore.STORE_BTREE_ROWCOUNT) {
@@ -176,7 +200,8 @@ class PageBtreeNode extends PageBtree {
 
     PageBtree split(int splitPoint) throws SQLException {
         int newPageId = index.getPageStore().allocatePage();
-        PageBtreeNode p2 = new PageBtreeNode(index, newPageId, parentPageId, index.getPageStore().createData());
+        PageBtreeNode p2 = new PageBtreeNode(index, newPageId, index.getPageStore().createData());
+        p2.parentPageId = parentPageId;
         if (onlyPosition) {
             // TODO optimize: maybe not required
             p2.onlyPosition = true;
@@ -226,7 +251,7 @@ class PageBtreeNode extends PageBtree {
     void find(PageBtreeCursor cursor, SearchRow first, boolean bigger) throws SQLException {
         int i = find(first, bigger, false, false);
         if (i > entryCount) {
-            if (parentPageId == Page.ROOT) {
+            if (parentPageId == PageBtree.ROOT) {
                 return;
             }
             PageBtreeNode next = (PageBtreeNode) index.getPage(parentPageId);
@@ -338,6 +363,7 @@ class PageBtreeNode extends PageBtree {
         data.reset();
         data.writeInt(parentPageId);
         data.writeByte((byte) (Page.TYPE_BTREE_NODE | (onlyPosition ? 0 : Page.FLAG_LAST)));
+        data.writeInt(index.getId());
         data.writeShortInt(entryCount);
         data.writeInt(rowCount);
         data.writeInt(childPageIds[entryCount]);
@@ -404,7 +430,7 @@ class PageBtreeNode extends PageBtree {
             }
         }
         if (i > entryCount) {
-            if (parentPageId == Page.ROOT) {
+            if (parentPageId == PageBtree.ROOT) {
                 cursor.setCurrent(null, 0);
                 return;
             }
@@ -433,7 +459,7 @@ class PageBtreeNode extends PageBtree {
             }
         }
         if (i < 0) {
-            if (parentPageId == Page.ROOT) {
+            if (parentPageId == PageBtree.ROOT) {
                 cursor.setCurrent(null, 0);
                 return;
             }

h2/src/main/org/h2/index/PageData.java

@@ -10,12 +10,17 @@ import java.sql.SQLException;
 import org.h2.engine.Session;
 import org.h2.result.Row;
 import org.h2.store.Data;
-import org.h2.store.Record;
+import org.h2.store.Page;
 
 /**
  * A page that contains data rows.
  */
-abstract class PageData extends Record {
+abstract class PageData extends Page {
+
+    /**
+     * This is a root page.
+     */
+    static final int ROOT = 0;
 
     /**
      * Indicator that the row count is not known.
@@ -52,9 +57,8 @@ abstract class PageData extends Record {
      */
     protected boolean written;
 
-    PageData(PageScanIndex index, int pageId, int parentPageId, Data data) {
+    PageData(PageScanIndex index, int pageId, Data data) {
         this.index = index;
-        this.parentPageId = parentPageId;
         this.data = data;
         setPos(pageId);
     }
@@ -95,11 +99,6 @@ abstract class PageData extends Record {
         return l;
     }
 
-    /**
-     * Read the data.
-     */
-    abstract void read() throws SQLException;
-
     /**
      * Add a row if possible. If it is possible this method returns -1, otherwise
      * the split point. It is always possible to add one row.

h2/src/main/org/h2/index/PageDataLeaf.java

@@ -15,6 +15,7 @@ import org.h2.message.Message;
 import org.h2.result.Row;
 import org.h2.store.Data;
 import org.h2.store.DataPage;
+import org.h2.store.Page;
 import org.h2.store.PageStore;
 
 /**
@@ -29,7 +30,7 @@ import org.h2.store.PageStore;
  * </li><li>data
  * </li></ul>
  */
-class PageDataLeaf extends PageData {
+public class PageDataLeaf extends PageData {
 
     private static final int KEY_OFFSET_PAIR_LENGTH = 6;
     private static final int KEY_OFFSET_PAIR_START = 11;
@@ -64,13 +65,28 @@ class PageDataLeaf extends PageData {
      */
     private int overflowRowSize;
 
-    PageDataLeaf(PageScanIndex index, int pageId, int parentPageId, Data data) {
-        super(index, pageId, parentPageId, data);
+    PageDataLeaf(PageScanIndex index, int pageId, Data data) {
+        super(index, pageId, data);
         start = KEY_OFFSET_PAIR_START;
     }
 
-    void read() throws SQLException {
-        data.setPos(4);
+    /**
+     * Read a data leaf page.
+     *
+     * @param index the index
+     * @param data the data
+     * @param pageId the page id
+     * @return the page
+     */
+    public static Page read(PageScanIndex index, Data data, int pageId) throws SQLException {
+        PageDataLeaf p = new PageDataLeaf(index, pageId, data);
+        p.read();
+        return p;
+    }
+
+    private void read() throws SQLException {
+        data.reset();
+        this.parentPageId = data.readInt();
         int type = data.readByte();
         int tableId = data.readInt();
         if (tableId != index.getId()) {
@@ -170,7 +186,7 @@ class PageDataLeaf extends PageData {
                     size = pageSize - PageDataOverflow.START_MORE;
                     next = index.getPageStore().allocatePage();
                 }
-                PageDataOverflow overflow = new PageDataOverflow(this, page, type, previous, next, data, dataOffset, size);
+                PageDataOverflow overflow = new PageDataOverflow(index, page, type, previous, next, data, dataOffset, size);
                 index.getPageStore().updateRecord(overflow, true, null);
                 dataOffset += size;
                 remaining -= size;
@@ -232,9 +248,8 @@ class PageDataLeaf extends PageData {
                 int pageSize = store.getPageSize();
                 data.setPos(pageSize);
                 int next = firstOverflowPageId;
-                int offset = pageSize;
                 do {
-                    PageDataOverflow page = index.getPageOverflow(next, this, offset);
+                    PageDataOverflow page = index.getPageOverflow(next);
                     next = page.readInto(data);
                 } while (next != 0);
                 overflowRowSize = data.length();
@@ -257,7 +272,8 @@ class PageDataLeaf extends PageData {
 
     PageData split(int splitPoint) throws SQLException {
         int newPageId = index.getPageStore().allocatePage();
-        PageDataLeaf p2 = new PageDataLeaf(index, newPageId, parentPageId, index.getPageStore().createData());
+        PageDataLeaf p2 = new PageDataLeaf(index, newPageId, index.getPageStore().createData());
+        p2.parentPageId = parentPageId;
         for (int i = splitPoint; i < entryCount;) {
             p2.addRowTry(getRowAt(splitPoint));
             removeRow(splitPoint);
@@ -274,7 +290,7 @@ class PageDataLeaf extends PageData {
     }
 
     PageDataLeaf getNextPage() throws SQLException {
-        if (parentPageId == Page.ROOT) {
+        if (parentPageId == PageData.ROOT) {
             return null;
         }
         PageDataNode next = (PageDataNode) index.getPage(parentPageId, -1);
@@ -289,7 +305,7 @@ class PageDataLeaf extends PageData {
         if (firstOverflowPageId == 0) {
             return;
         }
-        PageDataOverflow overflow = index.getPageOverflow(firstOverflowPageId, this, 0);
+        PageDataOverflow overflow = index.getPageOverflow(firstOverflowPageId);
         overflow.setParent(getPos());
         index.getPageStore().updateRecord(overflow, true, null);
     }
@@ -312,7 +328,7 @@ class PageDataLeaf extends PageData {
             PageStore store = index.getPageStore();
             int next = firstOverflowPageId;
             do {
-                PageDataOverflow page = index.getPageOverflow(next, this, 0);
+                PageDataOverflow page = index.getPageOverflow(next);
                 store.freePage(next, false, null);
                 next = page.getNextOverflow();
             } while (next != 0);

h2/src/main/org/h2/index/PageDataNode.java

@@ -7,12 +7,13 @@
 package org.h2.index;
 
 import java.sql.SQLException;
-
+import org.h2.constant.ErrorCode;
 import org.h2.engine.Session;
 import org.h2.message.Message;
 import org.h2.result.Row;
 import org.h2.store.Data;
 import org.h2.store.DataPage;
+import org.h2.store.Page;
 import org.h2.util.MemoryUtils;
 
 /**
@@ -20,17 +21,18 @@ import org.h2.util.MemoryUtils;
  * Format:
  * <ul><li>0-3: parent page id
  * </li><li>4-4: page type
- * </li><li>5-6: entry count
- * </li><li>7-10: row count of all children (-1 if not known)
- * </li><li>11-14: rightmost child page id
- * </li><li>15- entries: 4 bytes leaf page id, 4 bytes key
+ * </li><li>5-8: index id
+ * </li><li>9-10: entry count
+ * </li><li>11-14: row count of all children (-1 if not known)
+ * </li><li>15-18: rightmost child page id
+ * </li><li>19- entries: 4 bytes leaf page id, 4 bytes key
  * </li></ul>
  * The key is the largest key of the respective child, meaning
  * key[0] is the largest key of child[0].
  */
-class PageDataNode extends PageData {
+public class PageDataNode extends PageData {
 
-    private static final int ENTRY_START = 15;
+    private static final int ENTRY_START = 19;
 
     private static final int ENTRY_LENGTH = 8;
 
@@ -43,12 +45,34 @@ class PageDataNode extends PageData {
 
     private int rowCount = UNKNOWN_ROWCOUNT;
 
-    PageDataNode(PageScanIndex index, int pageId, int parentPageId, Data data) {
-        super(index, pageId, parentPageId, data);
+    PageDataNode(PageScanIndex index, int pageId, Data data) {
+        super(index, pageId, data);
+    }
+
+    /**
+     * Read a data node page.
+     *
+     * @param index the index
+     * @param data the data
+     * @param pageId the page id
+     * @return the page
+     */
+    public static Page read(PageScanIndex index, Data data, int pageId) throws SQLException {
+        PageDataNode p = new PageDataNode(index, pageId, data);
+        p.read();
+        return p;
     }
 
-    void read() {
-        data.setPos(5);
+    private void read() throws SQLException {
+        data.reset();
+        this.parentPageId = data.readInt();
+        data.readByte();
+        int indexId = data.readInt();
+        if (indexId != index.getId()) {
+            throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1,
+                    "page:" + getPos() + " expected index:" + index.getId() +
+                    "got:" + indexId);
+        }
         entryCount = data.readShortInt();
         rowCount = rowCountStored = data.readInt();
         childPageIds = new int[entryCount + 1];
@@ -122,7 +146,8 @@ class PageDataNode extends PageData {
 
     PageData split(int splitPoint) throws SQLException {
         int newPageId = index.getPageStore().allocatePage();
-        PageDataNode p2 = new PageDataNode(index, newPageId, parentPageId, index.getPageStore().createData());
+        PageDataNode p2 = new PageDataNode(index, newPageId, index.getPageStore().createData());
+        p2.parentPageId = parentPageId;
         int firstChild = childPageIds[splitPoint];
         for (int i = splitPoint; i < entryCount;) {
             p2.addChild(p2.entryCount, childPageIds[splitPoint + 1], keys[splitPoint]);
@@ -171,7 +196,7 @@ class PageDataNode extends PageData {
     PageDataLeaf getNextPage(int key) throws SQLException {
         int i = find(key) + 1;
         if (i > entryCount) {
-            if (parentPageId == Page.ROOT) {
+            if (parentPageId == PageData.ROOT) {
                 return null;
             }
             PageDataNode next = (PageDataNode) index.getPage(parentPageId, -1);
@@ -271,6 +296,7 @@ class PageDataNode extends PageData {
         data.reset();
         data.writeInt(parentPageId);
         data.writeByte((byte) Page.TYPE_DATA_NODE);
+        data.writeInt(index.getId());
         data.writeShortInt(entryCount);
         data.writeInt(rowCountStored);
         data.writeInt(childPageIds[entryCount]);

h2/src/main/org/h2/index/PageDataOverflow.java

@@ -11,29 +11,30 @@ import org.h2.constant.ErrorCode;
 import org.h2.message.Message;
 import org.h2.store.Data;
 import org.h2.store.DataPage;
-import org.h2.store.Record;
+import org.h2.store.Page;
 
 /**
  * Overflow data for a leaf page.
  * Format:
  * <ul><li>0-3: parent page id (0 for root)
  * </li><li>4-4: page type
- * </li><li>if there is more data: 5-8: next overflow page id
- * </li><li>otherwise: 5-6: remaining size
+ * </li><li>5-8: index id
+ * </li><li>if there is more data: 9-12: next overflow page id
+ * </li><li>otherwise: 9-10: remaining size
  * </li><li>data
  * </li></ul>
  */
-public class PageDataOverflow extends Record {
+public class PageDataOverflow extends Page {
 
     /**
      * The start of the data in the last overflow page.
      */
-    static final int START_LAST = 7;
+    static final int START_LAST = 11;
 
     /**
      * The start of the data in a overflow page that is not the last one.
      */
-    static final int START_MORE = 9;
+    static final int START_MORE = 13;
 
     /**
      * The index.
@@ -62,8 +63,8 @@ public class PageDataOverflow extends Record {
 
     private Data data;
 
-    PageDataOverflow(PageDataLeaf leaf, int pageId, int type, int previous, int next, Data allData, int offset, int size) {
-        this.index = leaf.index;
+    PageDataOverflow(PageScanIndex index, int pageId, int type, int previous, int next, Data allData, int offset, int size) {
+        this.index = index;
         setPos(pageId);
         this.type = type;
         this.parentPage = previous;
@@ -72,6 +73,7 @@ public class PageDataOverflow extends Record {
         data = index.getPageStore().createData();
         data.writeInt(parentPage);
         data.writeByte((byte) type);
+        data.writeInt(index.getId());
         if (type == Page.TYPE_DATA_OVERFLOW) {
             data.writeInt(nextPage);
         } else {
@@ -88,18 +90,39 @@ public class PageDataOverflow extends Record {
      * @param data the data page
      * @param offset the offset
      */
-    PageDataOverflow(PageDataLeaf leaf, int pageId, Data data, int offset) {
-        this.index = leaf.index;
+    PageDataOverflow(PageScanIndex index, int pageId, Data data) {
+        this.index = index;
         setPos(pageId);
         this.data = data;
     }
 
+    /**
+     * Read an overflow page.
+     *
+     * @param index the index
+     * @param data the data
+     * @param pageId the page id
+     * @return the page
+     */
+    public static Page read(PageScanIndex index, Data data, int pageId) throws SQLException {
+        PageDataOverflow p = new PageDataOverflow(index, pageId, data);
+        p.read();
+        return p;
+    }
+
     /**
      * Read the page.
      */
-    void read() throws SQLException {
+    private void read() throws SQLException {
+        data.reset();
         parentPage = data.readInt();
         type = data.readByte();
+        int indexId = data.readInt();
+        if (indexId != index.getId()) {
+            throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1,
+                    "page:" + getPos() + " expected index:" + index.getId() +
+                    " got:" + indexId + " type:" + type);
+        }
         if (type == (Page.TYPE_DATA_OVERFLOW | Page.FLAG_LAST)) {
             size = data.readShortInt();
             nextPage = 0;

h2/src/main/org/h2/index/PageScanIndex.java

@@ -12,8 +12,6 @@ import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
-import org.h2.constant.ErrorCode;
-import org.h2.constant.SysProperties;
 import org.h2.engine.Constants;
 import org.h2.engine.Session;
 import org.h2.log.UndoLogRecord;
@@ -22,7 +20,6 @@ import org.h2.result.Row;
 import org.h2.result.SearchRow;
 import org.h2.store.Data;
 import org.h2.store.PageStore;
-import org.h2.store.Record;
 import org.h2.table.Column;
 import org.h2.table.IndexColumn;
 import org.h2.table.TableData;
@@ -56,6 +53,7 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
         }
         tableData = table;
         this.store = database.getPageStore();
+        store.addIndex(this);
         if (!database.isPersistent()) {
             this.headPos = 0;
             throw Message.throwInternalError(table.getName());
@@ -67,7 +65,8 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
             // it should not for new tables, otherwise redo of other operations
             // must ensure this page is not used for other things
             store.addMeta(this, session, headPos);
-            PageDataLeaf root = new PageDataLeaf(this, headPos, Page.ROOT, store.createData());
+            PageDataLeaf root = new PageDataLeaf(this, headPos, store.createData());
+            root.parentPageId = PageData.ROOT;
             store.updateRecord(root, true, root.data);
         } else {
             this.headPos = headPos;
@@ -129,7 +128,8 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
             page1.setPageId(id);
             page1.setParentPageId(headPos);
             page2.setParentPageId(headPos);
-            PageDataNode newRoot = new PageDataNode(this, rootPageId, Page.ROOT, store.createData());
+            PageDataNode newRoot = new PageDataNode(this, rootPageId, store.createData());
+            newRoot.parentPageId = PageData.ROOT;
             newRoot.init(page1, pivot, page2);
             store.updateRecord(page1, true, page1.data);
             store.updateRecord(page2, true, page2.data);
@@ -156,20 +156,10 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
      * Read an overflow page page.
      *
      * @param id the page id
-     * @param leaf the leaf page
-     * @param offset the offset in bytes
      * @return the page
      */
-    PageDataOverflow getPageOverflow(int id, PageDataLeaf leaf, int offset) throws SQLException {
-        Record rec = store.getRecord(id);
-        if (rec != null) {
-            return (PageDataOverflow) rec;
-        }
-        Data data = store.readPage(id);
-        data.reset();
-        PageDataOverflow result = new PageDataOverflow(leaf, id, data, offset);
-        result.read();
-        return result;
+    PageDataOverflow getPageOverflow(int id) throws SQLException {
+        return (PageDataOverflow) store.getPage(id);
     }
 
     /**
@@ -180,41 +170,22 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
      * @return the page
      */
     PageData getPage(int id, int parent) throws SQLException {
-        Record rec = store.getRecord(id);
-        if (rec != null) {
-            if (SysProperties.CHECK) {
-                PageData result = (PageData) rec;
-                if (result.index.headPos != headPos) {
-                    throw Message.throwInternalError("Wrong index: " + result.index.getName() + ":" + result.index.headPos + " " + getName() + ":" + headPos);
-                }
-            }
-            return (PageData) rec;
-        }
-        Data data = store.readPage(id);
-        data.reset();
-        int parentPageId = data.readInt();
-        int type = data.readByte() & 255;
-        PageData result;
-        switch (type & ~Page.FLAG_LAST) {
-        case Page.TYPE_DATA_LEAF:
-            result = new PageDataLeaf(this, id, parentPageId, data);
-            break;
-        case Page.TYPE_DATA_NODE:
-            result = new PageDataNode(this, id, parentPageId, data);
-            break;
-        case Page.TYPE_EMPTY:
-            PageDataLeaf empty = new PageDataLeaf(this, id, parentPageId, data);
+        PageData p = (PageData) store.getPage(id);
+        if (p == null) {
+            Data data = store.createData();
+            PageDataLeaf empty = new PageDataLeaf(this, id, data);
+            empty.parentPageId = parent;
             return empty;
-        default:
-            throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1, "page=" + id + " type=" + type);
         }
-        result.read();
+        if (p.index.headPos != headPos) {
+            throw Message.throwInternalError("Wrong index: " + p.index.getName() + ":" + p.index.headPos + " " + getName() + ":" + headPos);
+        }
         if (parent != -1) {
-            if (result.getParentPageId() != parent) {
-                throw Message.throwInternalError(result + " parent " + result.getParentPageId() + " expected " + parent);
+            if (p.getParentPageId() != parent) {
+                throw Message.throwInternalError(p + " parent " + p.getParentPageId() + " expected " + parent);
             }
         }
-        return result;
+        return p;
     }
 
     public boolean canGetFirstOrLast() {
@@ -308,7 +279,8 @@ public class PageScanIndex extends BaseIndex implements RowIndex {
     private void removeAllRows() throws SQLException {
         PageData root = getPage(headPos, 0);
         root.freeChildren();
-        root = new PageDataLeaf(this, headPos, Page.ROOT, store.createData());
+        root = new PageDataLeaf(this, headPos, store.createData());
+        root.parentPageId = PageData.ROOT;
         store.removeRecord(headPos);
         store.updateRecord(root, true, null);
         rowCount = 0;

h2/src/main/org/h2/index/Page.java → h2/src/main/org/h2/store/Page.java

@@ -4,7 +4,8 @@
  * (http://h2database.com/html/license.html).
  * Initial Developer: H2 Group
  */
-package org.h2.index;
+package org.h2.store;
+
 
 /**
  * A page. Format:
@@ -13,7 +14,7 @@ package org.h2.index;
  * </li><li>page-type specific data
  * </li></ul>
  */
-public class Page {
+public abstract class Page extends Record {
 
     /**
      * This is the last page of a chain.
@@ -65,9 +66,4 @@ public class Page {
      */
     public static final int TYPE_STREAM_DATA = 8;
 
-    /**
-     * This is a root page.
-     */
-    static final int ROOT = 0;
-
 }

h2/src/main/org/h2/store/PageFreeList.java

@@ -7,7 +7,6 @@ package org.h2.store;
 
 import java.sql.SQLException;
 import org.h2.constant.ErrorCode;
-import org.h2.index.Page;
 import org.h2.message.Message;
 import org.h2.util.BitField;
 
@@ -20,7 +19,7 @@ import org.h2.util.BitField;
  * <li>5-remainder: data</li>
  * </ul>
  */
-public class PageFreeList extends Record {
+public class PageFreeList extends Page {
 
     private static final int DATA_START = 5;
 
@@ -30,13 +29,39 @@ public class PageFreeList extends Record {
     private boolean full;
     private Data data;
 
-    PageFreeList(PageStore store, int pageId) {
+    private PageFreeList(PageStore store, int pageId) {
         setPos(pageId);
         this.store = store;
         pageCount = (store.getPageSize() - DATA_START) * 8;
         used.set(0);
     }
 
+    /**
+     * Read a free-list page.
+     *
+     * @param store the page store
+     * @param data the data
+     * @param pageId the page id
+     * @return the page
+     */
+    static PageFreeList read(PageStore store, Data data, int pageId) throws SQLException {
+        PageFreeList p = new PageFreeList(store, pageId);
+        p.data = data;
+        p.read();
+        return p;
+    }
+
+    /**
+     * Create a new free-list page.
+     *
+     * @param store the page store
+     * @param pageId the page id
+     * @return the page
+     */
+    static PageFreeList create(PageStore store, int pageId) {
+        return new PageFreeList(store, pageId);
+    }
+
     /**
      * Allocate a page from the free list.
      *
@@ -114,15 +139,11 @@ public class PageFreeList extends Record {
     /**
      * Read the page from the disk.
      */
-    void read() throws SQLException {
-        data = store.createData();
-        store.readPage(getPos(), data);
+    private void read() throws SQLException {
+        data.reset();
         int p = data.readInt();
         int t = data.readByte();
-        if (t == Page.TYPE_EMPTY) {
-            return;
-        }
-        if (t != Page.TYPE_FREE_LIST || p != 0) {
+        if (p != 0) {
             throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1, "pos:" + getPos() + " type:" + t + " parent:" + p
                     + " expected type:" + Page.TYPE_FREE_LIST);
         }

h2/src/main/org/h2/store/PageInputStream.java

@@ -76,7 +76,7 @@ public class PageInputStream extends InputStream {
         }
     }
 
-    private void fillBuffer() throws SQLException {
+    private void fillBuffer() throws SQLException, EOFException {
         if (remaining > 0 || endOfFile) {
             return;
         }
@@ -87,8 +87,11 @@ public class PageInputStream extends InputStream {
         int next;
         while (true) {
             if (trunk == null) {
-                trunk = new PageStreamTrunk(store, trunkNext);
-                trunk.read();
+                trunk = (PageStreamTrunk) store.getPage(trunkNext);
+                if (trunk == null) {
+                    throw new EOFException();
+                }
+                trunk.resetIndex();
                 trunkNext = trunk.getNextTrunk();
             }
             if (trunk != null) {
@@ -104,8 +107,11 @@ public class PageInputStream extends InputStream {
             trace.debug("pageIn.readPage " + next);
         }
         dataPage = -1;
-        data = new PageStreamData(store, next, 0);
-        data.read();
+        data = (PageStreamData) store.getPage(next);
+        if (data == null) {
+            throw new EOFException();
+        }
+        data.initRead();
         remaining = data.getLength();
     }
 
@@ -120,8 +126,11 @@ public class PageInputStream extends InputStream {
         while (trunkPage != 0) {
             pages.set(trunkPage);
             store.allocatePage(trunkPage);
-            PageStreamTrunk t = new PageStreamTrunk(store, trunkPage);
-            t.read();
+            PageStreamTrunk t = (PageStreamTrunk) store.getPage(trunkPage);
+            if (t == null) {
+                break;
+            }
+            t.resetIndex();
             while (true) {
                 int n = t.getNextPageData();
                 if (n == -1) {

h2/src/main/org/h2/store/PageLog.java

@@ -189,10 +189,8 @@ public class PageLog {
             if (store.getRecord(firstTrunkPage) != null) {
                 throw Message.throwInternalError("" + store.getRecord(firstTrunkPage));
             }
-            PageStreamTrunk t = new PageStreamTrunk(store, this.firstTrunkPage);
-            try {
-                t.read();
-            } catch (SQLException e) {
+            PageStreamTrunk t = (PageStreamTrunk) store.getPage(this.firstTrunkPage);
+            if (t == null) {
                 store.freePage(firstTrunkPage, false, null);
                 // EOF
                 break;
@@ -621,9 +619,8 @@ public class PageLog {
     private int removeUntil(int firstTrunkPage, int firstDataPageToKeep) throws SQLException {
         trace.debug("log.removeUntil " + firstDataPageToKeep);
         while (true) {
-            // TODO keep trunk page in the cache
-            PageStreamTrunk t = new PageStreamTrunk(store, firstTrunkPage);
-            t.read();
+            PageStreamTrunk t = (PageStreamTrunk) store.getPage(firstTrunkPage);
+            t.resetIndex();
             if (t.contains(firstDataPageToKeep)) {
                 return t.getPos();
             }
@@ -725,8 +722,7 @@ public class PageLog {
      * @param commit whether the transaction should be committed
      */
     void setInDoubtTransactionState(int sessionId, int pageId, boolean commit) throws SQLException {
-        PageStreamData d = new PageStreamData(store, pageId, 0);
-        d.read();
+        PageStreamData d = (PageStreamData) store.getPage(pageId);
         d.initWrite();
         ByteArrayOutputStream buff = new ByteArrayOutputStream();
         DataOutputStream o = new DataOutputStream(buff);

h2/src/main/org/h2/store/PageOutputStream.java

@@ -98,13 +98,13 @@ public class PageOutputStream extends OutputStream {
                 pageIds[i] = reservedPages.get(i);
             }
             trunkNext = reservedPages.get(len);
-            trunk = new PageStreamTrunk(store, parent, trunkPageId, trunkNext, pageIds);
+            trunk = PageStreamTrunk.create(store, parent, trunkPageId, trunkNext, pageIds);
             pages++;
             trunk.write(null);
             reservedPages.removeRange(0, len + 1);
             nextData = trunk.getNextPageData();
         }
-        data = new PageStreamData(store, nextData, trunk.getPos());
+        data = PageStreamData.create(store, nextData, trunk.getPos());
         pages++;
         data.initWrite();
     }

h2/src/main/org/h2/store/PageStore.java

@@ -18,8 +18,12 @@ import org.h2.engine.Session;
 import org.h2.index.Cursor;
 import org.h2.index.Index;
 import org.h2.index.IndexType;
-import org.h2.index.Page;
 import org.h2.index.PageBtreeIndex;
+import org.h2.index.PageBtreeLeaf;
+import org.h2.index.PageBtreeNode;
+import org.h2.index.PageDataLeaf;
+import org.h2.index.PageDataNode;
+import org.h2.index.PageDataOverflow;
 import org.h2.index.PageScanIndex;
 import org.h2.log.InDoubtTransaction;
 import org.h2.log.LogSystem;
@@ -192,7 +196,7 @@ public class PageStore implements CacheWriter {
     private Schema metaSchema;
     private TableData metaTable;
     private PageScanIndex metaIndex;
-    private HashMap<Integer, Index> metaObjects;
+    private HashMap<Integer, Index> metaObjects = New.hashMap();
 
     /**
      * The map of reserved pages, to ensure index head pages
@@ -360,32 +364,87 @@ public class PageStore implements CacheWriter {
         if (free == -1 || free < 10) {
             return;
         }
-        Record rec = getRecord(full);
-        if (rec == null) {
+        Page p = getPage(full);
+    }
 
-        } else {
-            Data page = Data.create(database, pageSize);
-            readPage(full, page);
-            int parent = page.readInt();
-            int type = page.readByte();
-            boolean last = (type & Page.FLAG_LAST) != 0;
-            type = type & ~Page.FLAG_LAST;
-            System.out.println("last page is " + type + " parent: " + parent);
-            switch (type) {
-            case Page.TYPE_EMPTY:
-                break;
-            case Page.TYPE_FREE_LIST:
-                break;
-            case Page.TYPE_DATA_LEAF:
-                break;
-            case Page.TYPE_DATA_NODE:
-            case Page.TYPE_DATA_OVERFLOW:
-            case Page.TYPE_BTREE_LEAF:
-            case Page.TYPE_BTREE_NODE:
-            case Page.TYPE_STREAM_TRUNK:
-            case Page.TYPE_STREAM_DATA:
+    /**
+     * Read a page from the store.
+     *
+     * @param pageId the page id
+     * @return the page
+     */
+    public Page getPage(int pageId) throws SQLException {
+        Record rec = getRecord(pageId);
+        if (rec != null) {
+            return (Page) rec;
+        }
+        Data data = Data.create(database, pageSize);
+        readPage(pageId, data);
+        data.readInt();
+        int type = data.readByte();
+        Page p;
+        switch (type & ~Page.FLAG_LAST) {
+        case Page.TYPE_EMPTY:
+            return null;
+        case Page.TYPE_FREE_LIST:
+            p = PageFreeList.read(this, data, pageId);
+            break;
+        case Page.TYPE_DATA_LEAF: {
+            int indexId = data.readInt();
+            PageScanIndex index = (PageScanIndex) metaObjects.get(indexId);
+            if (index == null) {
+                Message.throwInternalError("index not found " + indexId);
             }
+            p = PageDataLeaf.read(index, data, pageId);
+            break;
         }
+        case Page.TYPE_DATA_NODE: {
+            int indexId = data.readInt();
+            PageScanIndex index = (PageScanIndex) metaObjects.get(indexId);
+            if (index == null) {
+                Message.throwInternalError("index not found " + indexId);
+            }
+            p = PageDataNode.read(index, data, pageId);
+            break;
+        }
+        case Page.TYPE_DATA_OVERFLOW: {
+            int indexId = data.readInt();
+            PageScanIndex index = (PageScanIndex) metaObjects.get(indexId);
+            if (index == null) {
+                Message.throwInternalError("index not found " + indexId);
+            }
+            p = PageDataOverflow.read(index, data, pageId);
+            break;
+        }
+        case Page.TYPE_BTREE_LEAF: {
+            int indexId = data.readInt();
+            PageBtreeIndex index = (PageBtreeIndex) metaObjects.get(indexId);
+            if (index == null) {
+                Message.throwInternalError("index not found " + indexId);
+            }
+            p = PageBtreeLeaf.read(index, data, pageId);
+            break;
+        }
+        case Page.TYPE_BTREE_NODE: {
+            int indexId = data.readInt();
+            PageBtreeIndex index = (PageBtreeIndex) metaObjects.get(indexId);
+            if (index == null) {
+                Message.throwInternalError("index not found " + indexId);
+            }
+            p = PageBtreeNode.read(index, data, pageId);
+            break;
+        }
+        case Page.TYPE_STREAM_TRUNK:
+            p = PageStreamTrunk.read(this, data, pageId);
+            break;
+        case Page.TYPE_STREAM_DATA:
+            p = PageStreamData.read(this, data, pageId);
+            break;
+        default:
+            throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1, "page=" + pageId + " type=" + type);
+        }
+        cache.put(p);
+        return p;
     }
 
     /**
@@ -608,12 +667,12 @@ public class PageStore implements CacheWriter {
         while (p >= pageCount) {
             increaseFileSize(INCREMENT_PAGES);
         }
-        PageFreeList list = (PageFreeList) getRecord(p);
+        PageFreeList list = null;
+        if (p < pageCount) {
+            list = (PageFreeList) getPage(p);
+        }
         if (list == null) {
-            list = new PageFreeList(this, p);
-            if (p < pageCount) {
-                list.read();
-            }
+            list = PageFreeList.create(this, p);
             cache.put(list);
         }
         return list;
@@ -987,7 +1046,7 @@ public class PageStore implements CacheWriter {
                 META_TABLE_ID, cols, false, true, true, false, headPos, systemSession);
         metaIndex = (PageScanIndex) metaTable.getScanIndex(
                 systemSession);
-        metaObjects = New.hashMap();
+        metaObjects.clear();
         metaObjects.put(-1, metaIndex);
     }
 
@@ -1076,6 +1135,15 @@ public class PageStore implements CacheWriter {
         metaObjects.put(id, meta);
     }
 
+    /**
+     * Add an index to the in-memory index map.
+     *
+     * @param index the index
+     */
+    public void addIndex(Index index) {
+        metaObjects.put(index.getId(), index);
+    }
+
     /**
      * Add the meta data of an index.
      *
@@ -1124,6 +1192,7 @@ public class PageStore implements CacheWriter {
     public void removeMeta(Index index, Session session) throws SQLException {
         if (!recoveryRunning) {
             removeMetaIndex(index, session);
+            metaObjects.remove(index.getId());
         }
     }
 

h2/src/main/org/h2/store/PageStreamData.java

@@ -7,9 +7,6 @@
 package org.h2.store;
 
 import java.sql.SQLException;
-import org.h2.constant.ErrorCode;
-import org.h2.index.Page;
-import org.h2.message.Message;
 
 /**
  * A data page of a stream. The format is:
@@ -20,7 +17,7 @@ import org.h2.message.Message;
  * <li>9-remainder: data</li>
  * </ul>
  */
-public class PageStreamData extends Record {
+public class PageStreamData extends Page {
 
     private static final int LENGTH_START = 5;
     private static final int DATA_START = 9;
@@ -31,25 +28,47 @@ public class PageStreamData extends Record {
     private int remaining;
     private int length;
 
-    PageStreamData(PageStore store, int pageId, int trunk) {
+    private PageStreamData(PageStore store, int pageId, int trunk) {
         setPos(pageId);
         this.store = store;
         this.trunk = trunk;
     }
 
+    /**
+     * Read a stream data page.
+     *
+     * @param store the page store
+     * @param data the data
+     * @param pageId the page id
+     * @return the page
+     */
+    static PageStreamData read(PageStore store, Data data, int pageId) {
+        PageStreamData p = new PageStreamData(store, pageId, 0);
+        p.data = data;
+        p.read();
+        return p;
+    }
+
+    /**
+     * Create a new stream trunk page.
+     *
+     * @param store the page store
+     * @param pageId the page id
+     * @param trunk the trunk page
+     * @return the page
+     */
+    static PageStreamData create(PageStore store, int pageId, int trunk) {
+        return new PageStreamData(store, pageId, trunk);
+    }
+
     /**
      * Read the page from the disk.
      */
-    void read() throws SQLException {
-        data = store.createData();
-        store.readPage(getPos(), data);
+    private void read() {
+        data.reset();
         trunk = data.readInt();
         data.setPos(4);
-        int t = data.readByte();
-        if (t != Page.TYPE_STREAM_DATA) {
-            throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1, "pos:" + getPos() + " type:" + t +
-                    " expected type:" + Page.TYPE_STREAM_DATA);
-        }
+        data.readByte();
         length = data.readInt();
     }
 
@@ -133,4 +152,12 @@ public class PageStreamData extends Record {
         return store.getPageSize() >> 2;
     }
 
+    /**
+     * Reset the index.
+     */
+    void initRead() {
+        data.setPos(DATA_START);
+        remaining = length;
+    }
+
 }
\ No newline at end of file

h2/src/main/org/h2/store/PageStreamTrunk.java

@@ -7,10 +7,6 @@
 package org.h2.store;
 
 import java.sql.SQLException;
-import org.h2.constant.ErrorCode;
-import org.h2.index.Page;
-import org.h2.message.Message;
-import org.h2.util.MemoryUtils;
 
 /**
  * A trunk page of a stream. It contains the page numbers of the stream, and
@@ -23,7 +19,7 @@ import org.h2.util.MemoryUtils;
  * <li>13-remainder: page ids</li>
  * </ul>
  */
-public class PageStreamTrunk extends Record {
+public class PageStreamTrunk extends Page {
 
     private static final int DATA_START = 13;
 
@@ -35,7 +31,7 @@ public class PageStreamTrunk extends Record {
     private Data data;
     private int index;
 
-    PageStreamTrunk(PageStore store, int parent, int pageId, int next, int[] pageIds) {
+    private PageStreamTrunk(PageStore store, int parent, int pageId, int next, int[] pageIds) {
         setPos(pageId);
         this.parent = parent;
         this.store = store;
@@ -44,28 +40,47 @@ public class PageStreamTrunk extends Record {
         this.pageIds = pageIds;
     }
 
-    PageStreamTrunk(PageStore store, int pageId) {
+    private PageStreamTrunk(PageStore store, Data data, int pageId) {
         setPos(pageId);
+        this.data = data;
         this.store = store;
     }
 
+    /**
+     * Read a stream trunk page.
+     *
+     * @param store the page store
+     * @param data the data
+     * @param pageId the page id
+     * @return the page
+     */
+    static PageStreamTrunk read(PageStore store, Data data, int pageId) {
+        PageStreamTrunk p = new PageStreamTrunk(store, data, pageId);
+        p.read();
+        return p;
+    }
+
+    /**
+     * Create a new stream trunk page.
+     *
+     * @param store the page store
+     * @param parent the parent page
+     * @param pageId the page id
+     * @param next the next trunk page
+     * @param pageIds the stream data page ids
+     * @return the page
+     */
+    static PageStreamTrunk create(PageStore store, int parent, int pageId, int next, int[] pageIds) {
+        return new PageStreamTrunk(store, parent, pageId, next, pageIds);
+    }
+
     /**
      * Read the page from the disk.
      */
-    void read() throws SQLException {
-        data = store.createData();
-        store.readPage(getPos(), data);
+    private void read() {
+        data.reset();
         parent = data.readInt();
-        int t = data.readByte();
-        if (t == Page.TYPE_EMPTY) {
-            // end of file
-            pageIds = MemoryUtils.EMPTY_INTS;
-            return;
-        }
-        if (t != Page.TYPE_STREAM_TRUNK) {
-            throw Message.getSQLException(ErrorCode.FILE_CORRUPTED_1, "pos:" + getPos() + " type:" + t + " parent:" + parent
-                    + " expected type:" + Page.TYPE_STREAM_TRUNK);
-        }
+        data.readByte();
         nextTrunk = data.readInt();
         pageCount = data.readInt();
         pageIds = new int[pageCount];
@@ -74,6 +89,13 @@ public class PageStreamTrunk extends Record {
         }
     }
 
+    /**
+     * Reset the read/write index.
+     */
+    void resetIndex() {
+        index = 0;
+    }
+
     void setNextDataPage(int page) {
         pageIds[index++] = page;
     }

h2/src/main/org/h2/tools/Recover.java

@@ -27,7 +27,6 @@ import org.h2.command.Parser;
 import org.h2.engine.Constants;
 import org.h2.engine.DbObject;
 import org.h2.engine.MetaRecord;
-import org.h2.index.Page;
 import org.h2.log.LogFile;
 import org.h2.message.Message;
 import org.h2.message.Trace;
@@ -41,6 +40,7 @@ import org.h2.store.DiskFile;
 import org.h2.store.FileLister;
 import org.h2.store.FileStore;
 import org.h2.store.FileStoreInputStream;
+import org.h2.store.Page;
 import org.h2.store.PageFreeList;
 import org.h2.store.PageLog;
 import org.h2.store.PageStore;