org.h2.store.FileStoreOutputStream Maven / Gradle / Ivy
/*
* Copyright 2004-2019 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (https://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.store;
import java.io.OutputStream;
import java.util.Arrays;
import org.h2.engine.Constants;
import org.h2.tools.CompressTool;
/**
* An output stream that is backed by a file store.
*/
public class FileStoreOutputStream extends OutputStream {
private FileStore store;
private final Data page;
private final String compressionAlgorithm;
private final CompressTool compress;
private final byte[] buffer = { 0 };
public FileStoreOutputStream(FileStore store, DataHandler handler,
String compressionAlgorithm) {
this.store = store;
if (compressionAlgorithm != null) {
this.compress = CompressTool.getInstance();
this.compressionAlgorithm = compressionAlgorithm;
} else {
this.compress = null;
this.compressionAlgorithm = null;
}
page = Data.create(handler, Constants.FILE_BLOCK_SIZE, true);
}
@Override
public void write(int b) {
buffer[0] = (byte) b;
write(buffer);
}
@Override
public void write(byte[] buff) {
write(buff, 0, buff.length);
}
@Override
public void write(byte[] buff, int off, int len) {
if (len > 0) {
page.reset();
if (compress != null) {
if (off != 0 || len != buff.length) {
buff = Arrays.copyOfRange(buff, off, off + len);
off = 0;
}
int uncompressed = len;
buff = compress.compress(buff, compressionAlgorithm);
len = buff.length;
page.checkCapacity(2 * Data.LENGTH_INT + len);
page.writeInt(len);
page.writeInt(uncompressed);
page.write(buff, off, len);
} else {
page.checkCapacity(Data.LENGTH_INT + len);
page.writeInt(len);
page.write(buff, off, len);
}
page.fillAligned();
store.write(page.getBytes(), 0, page.length());
}
}
@Override
public void close() {
if (store != null) {
try {
store.close();
} finally {
store = null;
}
}
}
}