/* (non-Javadoc)
* @see com.ongraphdb.store.DiskSore1#shutdown()
*/
public void shutdown() throws IOException {
mappedDataBuffer.force();
mappedDataBuffer.clear();
dataLock.release();
dataChannel.close();
unmap(mappedDataBuffer);
Runtime.getRuntime().removeShutdownHook(shutdownHookThread);
}
public synchronized void close() {
try {
if (activateMemoryMappedBuffers) {
buffer.force();
}
storedFile.close();
closed = true;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
public void flush() {
synchronized (this) {
if (this.closed) return;
if (this.dirty) {
MappedByteBuffer srcBuf = (MappedByteBuffer) this.threadLocalBuffer.getSourceBuffer();
srcBuf.force();
this.dirty = false;
if (logger.isDebugEnabled())
logger.debug("Mapped page for " + this.pageFile + " was just flushed.");
}
}
}
/** @tests {@link java.nio.MappedByteBuffer#force()} */
public void test_force() throws IOException {
// buffer was not mapped in read/write mode
FileInputStream fileInputStream = new FileInputStream(tmpFile);
FileChannel fileChannelRead = fileInputStream.getChannel();
MappedByteBuffer mmbRead = fileChannelRead.map(MapMode.READ_ONLY, 0, fileChannelRead.size());
mmbRead.force();
FileInputStream inputStream = new FileInputStream(tmpFile);
FileChannel fileChannelR = inputStream.getChannel();
MappedByteBuffer resultRead = fileChannelR.map(MapMode.READ_ONLY, 0, fileChannelR.size());
// If this buffer was not mapped in read/write mode, then invoking this method has no effect.
assertEquals(
"Invoking force() should have no effect when this buffer was not mapped in read/write mode",
mmbRead,
resultRead);
// Buffer was mapped in read/write mode
RandomAccessFile randomFile = new RandomAccessFile(tmpFile, "rw");
FileChannel fileChannelReadWrite = randomFile.getChannel();
MappedByteBuffer mmbReadWrite =
fileChannelReadWrite.map(FileChannel.MapMode.READ_WRITE, 0, fileChannelReadWrite.size());
mmbReadWrite.put((byte) 'o');
mmbReadWrite.force();
RandomAccessFile random = new RandomAccessFile(tmpFile, "rw");
FileChannel fileChannelRW = random.getChannel();
MappedByteBuffer resultReadWrite =
fileChannelRW.map(FileChannel.MapMode.READ_WRITE, 0, fileChannelRW.size());
// Invoking force() will change the buffer
assertFalse(mmbReadWrite.equals(resultReadWrite));
fileChannelRead.close();
fileChannelR.close();
fileChannelReadWrite.close();
fileChannelRW.close();
}
@Override
public void close() throws BlockStoreException {
try {
buffer.force();
if (System.getProperty("os.name").toLowerCase().contains("win")) {
log.info("Windows mmap hack: Forcing buffer cleaning");
WindowsMMapHack.forceRelease(buffer);
}
buffer = null; // Allow it to be GCd and the underlying file mapping to go away.
randomAccessFile.close();
} catch (IOException e) {
throw new BlockStoreException(e);
}
}
public synchronized void flush(List<Update> updates) {
Assert.state(storedFile != null, "The FileStorage is not initialized");
try {
for (Update update : updates) {
ensureCapacity(update.index * BYTES_IN_LONG + BYTES_IN_LONG);
if (activateMemoryMappedBuffers) {
buffer.putLong(update.index * BYTES_IN_LONG, update.value);
} else {
storedFile.seek(update.index * BYTES_IN_LONG);
storedFile.writeLong(update.value);
}
}
if (activateMemoryMappedBuffers) {
buffer.force();
}
storedFile.getFD().sync();
} catch (Exception e) {
throw new RuntimeException(e);
}
}
@Override
public void flush() {
((MappedByteBuffer) bb).force();
}
public static void main(String[] argv) throws Exception {
// Create a temp file and get a channel connected to it
File tempFile = File.createTempFile("mmaptest", null);
RandomAccessFile file = new RandomAccessFile(tempFile, "rw");
FileChannel channel = file.getChannel();
// write strings to file by channel
ByteBuffer temp = ByteBuffer.allocate(100);
temp.put("This is the file content".getBytes());
temp.flip();
channel.write(temp, 0);
temp.clear();
temp.put("This is more file content".getBytes());
temp.flip();
channel.write(temp, 8192);
// readonly
MappedByteBuffer ro = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size());
// read and write
MappedByteBuffer rw = channel.map(FileChannel.MapMode.READ_WRITE, 0, channel.size());
// copy on write
MappedByteBuffer cow = channel.map(FileChannel.MapMode.PRIVATE, 0, channel.size());
System.out.println("Begin");
// ro、rw、cow 相同
showBuffers(ro, rw, cow);
// Modify the copy-on-write buffer，copy-on-write不会影响数据源
cow.position(8);
cow.put("COW".getBytes());
System.out.println("Change to COW buffer");
showBuffers(ro, rw, cow);
// Modify the read/write buffer，read/write会影响数据源
rw.position(9);
rw.put(" R/W ".getBytes());
rw.position(8194);
rw.put(" R/W ".getBytes());
rw.force();
System.out.println("Change to R/W buffer");
showBuffers(ro, rw, cow);
// Write to the file through the channel; hit both pages
temp.clear();
temp.put("Channel write ".getBytes());
temp.flip();
channel.write(temp, 0);
temp.rewind();
channel.write(temp, 8202);
System.out.println("Write on channel");
showBuffers(ro, rw, cow);
// Modify the copy-on-write buffer again
cow.position(8207);
cow.put(" COW2 ".getBytes());
System.out.println("Second change to COW buffer");
showBuffers(ro, rw, cow);
// Modify the read/write buffer
rw.position(0);
rw.put(" R/W2 ".getBytes());
rw.position(8210);
rw.put(" R/W2 ".getBytes());
rw.force();
System.out.println("Second change to R/W buffer");
showBuffers(ro, rw, cow);
}