Clob.getSubString and Blob.getBytes are now up to 3 times faster.

h2/src/docsrc/html/changelog.html

@@ -18,7 +18,8 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>New database setting DEFAULT_CONNECTION (disabled by default)
+<ul><li>Clob.getSubString and Blob.getBytes are now up to 3 times faster.
+</li><li>New database setting DEFAULT_CONNECTION (disabled by default)
     to support DriverManager.getConnection("jdbc:default:connection").
     Please note the Oracle JDBC driver will try to resolve this database URL if it is loaded before the H2 driver.
 </li><li>JaQu: the static map Db.TOKENS was not synchronized.

h2/src/main/org/h2/jdbc/JdbcBlob.java

@@ -58,21 +58,7 @@ public class JdbcBlob extends TraceObject implements Blob {
                     return precision;
                 }
             }
-            long size = 0;
-            InputStream in = value.getInputStream();
-            try {
-                byte[] buff = new byte[Constants.IO_BUFFER_SIZE];
-                while (true) {
-                    int len = in.read(buff, 0, Constants.IO_BUFFER_SIZE);
-                    if (len <= 0) {
-                        break;
-                    }
-                    size += len;
-                }
-            } finally {
-                in.close();
-            }
-            return size;
+            return IOUtils.copyAndCloseInput(value.getInputStream(), null);
         } catch (Exception e) {
             throw logAndConvert(e);
         }
@@ -106,14 +92,7 @@ public class JdbcBlob extends TraceObject implements Blob {
             InputStream in = value.getInputStream();
             try {
                 IOUtils.skipFully(in, pos - 1);
-                while (length > 0) {
-                    int x = in.read();
-                    if (x < 0) {
-                        break;
-                    }
-                    out.write(x);
-                    length--;
-                }
+                IOUtils.copy(in, out, length);
             } finally {
                 in.close();
             }

h2/src/main/org/h2/jdbc/JdbcClob.java

@@ -13,6 +13,7 @@ import java.io.PipedInputStream;
 import java.io.PipedOutputStream;
 import java.io.Reader;
 import java.io.StringReader;
+import java.io.StringWriter;
 import java.io.Writer;
 import java.sql.Clob;
 //## Java 1.6 begin ##
@@ -63,21 +64,7 @@ public class JdbcClob extends TraceObject implements Clob
                     return precision;
                 }
             }
-            Reader in = value.getReader();
-            try {
-                long size = 0;
-                char[] buff = new char[Constants.IO_BUFFER_SIZE];
-                while (true) {
-                    int len = in.read(buff, 0, Constants.IO_BUFFER_SIZE);
-                    if (len <= 0) {
-                        break;
-                    }
-                    size += len;
-                }
-                return size;
-            } finally {
-                in.close();
-            }
+            return IOUtils.copyAndCloseInput(value.getReader(), null, Long.MAX_VALUE);
         } catch (Exception e) {
             throw logAndConvert(e);
         }
@@ -196,21 +183,15 @@ public class JdbcClob extends TraceObject implements Clob
             if (length < 0) {
                 throw DbException.getInvalidValueException("length", length);
             }
-            StringBuilder buff = new StringBuilder(Math.min(4096, length));
+            StringWriter writer = new StringWriter(Math.min(Constants.IO_BUFFER_SIZE, length));
             Reader reader = value.getReader();
             try {
                 IOUtils.skipFully(reader, pos - 1);
-                for (int i = 0; i < length; i++) {
-                    int ch = reader.read();
-                    if (ch < 0) {
-                        break;
-                    }
-                    buff.append((char) ch);
-                }
+                IOUtils.copyAndCloseInput(reader, writer, length);
             } finally {
                 reader.close();
             }
-            return buff.toString();
+            return writer.toString();
         } catch (Exception e) {
             throw logAndConvert(e);
         }

h2/src/main/org/h2/server/web/WebThread.java

@@ -354,21 +354,13 @@ class WebThread extends WebApp implements Runnable {
         len -= headerBytes;
         File file = new File(WebServer.TRANSFER, fileName);
         OutputStream out = new FileOutputStream(file);
-        byte[] bytes = Utils.newBytes(Constants.IO_BUFFER_SIZE);
-        while (len > 0) {
-            int l = Math.min(Constants.IO_BUFFER_SIZE, len);
-            l = in.read(bytes, 0, l);
-            if (l < 0) {
-                break;
-            }
-            out.write(bytes, 0, l);
-            len -= l;
-        }
+        IOUtils.copy(in, out, len);
         out.close();
         // remove the boundary
         RandomAccessFile f = new RandomAccessFile(file, "rw");
         int testSize = (int) Math.min(f.length(), Constants.IO_BUFFER_SIZE);
         f.seek(f.length() - testSize);
+        byte[] bytes = Utils.newBytes(Constants.IO_BUFFER_SIZE);
         f.readFully(bytes, 0, testSize);
         String s = new String(bytes, "ASCII");
         int x = s.lastIndexOf(boundary);

h2/src/main/org/h2/store/fs/FileSystemDisk.java

@@ -18,7 +18,6 @@ import java.net.URL;
 
 import org.h2.constant.ErrorCode;
 import org.h2.constant.SysProperties;
-import org.h2.engine.Constants;
 import org.h2.message.DbException;
 import org.h2.util.IOUtils;
 import org.h2.util.StringUtils;
@@ -322,17 +321,9 @@ public class FileSystemDisk extends FileSystem {
         OutputStream out = null;
         InputStream in = null;
         try {
-            out = IOUtils.openFileOutputStream(target, false);
             in = IOUtils.openFileInputStream(source);
-            byte[] buffer = new byte[Constants.IO_BUFFER_SIZE];
-            while (true) {
-                int len = in.read(buffer);
-                if (len < 0) {
-                    break;
-                }
-                out.write(buffer, 0, len);
-            }
-            out.close();
+            out = IOUtils.openFileOutputStream(target, false);
+            IOUtils.copy(in, out);
         } catch (IOException e) {
             throw DbException.convertIOException(e, "original: " + source + " copy: " + target);
         } finally {

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

@@ -280,24 +280,15 @@ public class Recover extends Tool implements DataHandler {
     private void dumpLob(String fileName, boolean lobCompression) {
         OutputStream fileOut = null;
         FileStore fileStore = null;
-        int size = 0;
+        long size = 0;
         String n = fileName + (lobCompression ? ".comp" : "") + ".txt";
         InputStream in = null;
         try {
             fileOut = IOUtils.openFileOutputStream(n, false);
             fileStore = FileStore.open(null, fileName, "r");
             fileStore.init();
-            in = new BufferedInputStream(new FileStoreInputStream(fileStore, this, lobCompression, false));
-            byte[] buffer = new byte[Constants.IO_BUFFER_SIZE];
-            while (true) {
-                int l = in.read(buffer);
-                if (l < 0) {
-                    break;
-                }
-                fileOut.write(buffer, 0, l);
-                size += l;
-            }
-            fileOut.close();
+            in = new FileStoreInputStream(fileStore, this, lobCompression, false);
+            size = IOUtils.copy(in, fileOut);
         } catch (Throwable e) {
             // this is usually not a problem, because we try both compressed and
             // uncompressed

h2/src/main/org/h2/util/IOUtils.java

@@ -33,8 +33,6 @@ import org.h2.store.fs.FileSystem;
  */
 public class IOUtils {
 
-    private static final int BUFFER_BLOCK_SIZE = 4 * 1024;
-
     private IOUtils() {
         // utility class
     }
@@ -126,7 +124,7 @@ public class IOUtils {
      * input stream. Exceptions while closing are ignored.
      *
      * @param in the input stream
-     * @param out the output stream
+     * @param out the output stream (null if writing is not required)
      * @return the number of bytes copied
      */
     public static long copyAndCloseInput(InputStream in, OutputStream out) throws IOException {
@@ -144,22 +142,40 @@ public class IOUtils {
      * are kept open.
      *
      * @param in the input stream
-     * @param out the output stream
+     * @param out the output stream (null if writing is not required)
      * @return the number of bytes copied
      */
     public static long copy(InputStream in, OutputStream out) throws IOException {
+        return copy(in, out, Long.MAX_VALUE);
+    }
+
+    /**
+     * Copy all data from the input stream to the output stream. Both streams
+     * are kept open.
+     *
+     * @param in the input stream
+     * @param out the output stream (null if writing is not required)
+     * @param length the maximum number of bytes to copy
+     * @return the number of bytes copied
+     */
+    public static long copy(InputStream in, OutputStream out, long length) throws IOException {
         try {
-            long written = 0;
-            byte[] buffer = new byte[4 * 1024];
-            while (true) {
-                int len = in.read(buffer);
+            long copied = 0;
+            int len = (int) Math.min(length, Constants.IO_BUFFER_SIZE);
+            byte[] buffer = new byte[len];
+            while (length > 0) {
+                len = in.read(buffer, 0, len);
                 if (len < 0) {
                     break;
                 }
-                out.write(buffer, 0, len);
-                written += len;
+                if (out != null) {
+                    out.write(buffer, 0, len);
+                }
+                copied += len;
+                length -= len;
+                len = (int) Math.min(length, Constants.IO_BUFFER_SIZE);
             }
-            return written;
+            return copied;
         } catch (Exception e) {
             throw DbException.convertToIOException(e);
         }
@@ -170,22 +186,28 @@ public class IOUtils {
      * Exceptions while closing are ignored.
      *
      * @param in the reader
-     * @param out the writer
+     * @param out the writer (null if writing is not required)
+     * @param length the maximum number of bytes to copy
      * @return the number of characters copied
      */
-    public static long copyAndCloseInput(Reader in, Writer out) throws IOException {
+    public static long copyAndCloseInput(Reader in, Writer out, long length) throws IOException {
         try {
-            long written = 0;
-            char[] buffer = new char[4 * 1024];
-            while (true) {
-                int len = in.read(buffer);
+            long copied = 0;
+            int len = (int) Math.min(length, Constants.IO_BUFFER_SIZE);
+            char[] buffer = new char[len];
+            while (length > 0) {
+                len = in.read(buffer, 0, len);
                 if (len < 0) {
                     break;
                 }
-                out.write(buffer, 0, len);
-                written += len;
+                if (out != null) {
+                    out.write(buffer, 0, len);
+                }
+                length -= len;
+                len = (int) Math.min(length, Constants.IO_BUFFER_SIZE);
+                copied += len;
             }
-            return written;
+            return copied;
         } catch (Exception e) {
             throw DbException.convertToIOException(e);
         } finally {
@@ -253,18 +275,9 @@ public class IOUtils {
             if (length <= 0) {
                 length = Integer.MAX_VALUE;
             }
-            int block = Math.min(BUFFER_BLOCK_SIZE, length);
+            int block = Math.min(Constants.IO_BUFFER_SIZE, length);
             ByteArrayOutputStream out = new ByteArrayOutputStream(block);
-            byte[] buff = new byte[block];
-            while (length > 0) {
-                int len = Math.min(block, length);
-                len = in.read(buff, 0, len);
-                if (len < 0) {
-                    break;
-                }
-                out.write(buff, 0, len);
-                length -= len;
-            }
+            copy(in, out, length);
             return out.toByteArray();
         } catch (Exception e) {
             throw DbException.convertToIOException(e);
@@ -286,18 +299,9 @@ public class IOUtils {
             if (length <= 0) {
                 length = Integer.MAX_VALUE;
             }
-            int block = Math.min(BUFFER_BLOCK_SIZE, length);
-            StringWriter out = new StringWriter(length == Integer.MAX_VALUE ? block : length);
-            char[] buff = new char[block];
-            while (length > 0) {
-                int len = Math.min(block, length);
-                len = in.read(buff, 0, len);
-                if (len < 0) {
-                    break;
-                }
-                out.write(buff, 0, len);
-                length -= len;
-            }
+            int block = Math.min(Constants.IO_BUFFER_SIZE, length);
+            StringWriter out = new StringWriter(block);
+            copyAndCloseInput(in, out, length);
             return out.toString();
         } finally {
             in.close();

h2/src/main/org/h2/util/SourceCompiler.java

@@ -218,15 +218,7 @@ public class SourceCompiler {
     private static void copyInThread(final InputStream in, final OutputStream out) {
         new Task() {
             public void call() throws IOException {
-                while (true) {
-                    int x = in.read();
-                    if (x < 0) {
-                        return;
-                    }
-                    if (out != null) {
-                        out.write(x);
-                    }
-                }
+                IOUtils.copy(in, out);
             }
         }.execute();
     }