/*
* Copyright (C) 2014 Indeed Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
* in compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the
* License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.indeed.imhotep.io;
import com.google.common.base.Throwables;
import org.apache.log4j.Logger;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.IllegalBlockingModeException;
import java.nio.channels.SelectableChannel;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.spi.SelectorProvider;
/**
* @author jplaisance
*/
public final class BufferedWritableSelectableChannel extends WritableSelectableChannel {
private static final Logger log = Logger.getLogger(BufferedWritableSelectableChannel.class);
private final ByteBuffer buffer = ByteBuffer.allocate(16384);
private final WritableSelectableChannel wrapped;
private boolean closed = false;
public BufferedWritableSelectableChannel(final WritableSelectableChannel wrapped) {
this.wrapped = wrapped;
}
public SelectorProvider provider() {
return wrapped.provider();
}
public int validOps() {
return wrapped.validOps();
}
public boolean isRegistered() {
return wrapped.isRegistered();
}
public SelectionKey keyFor(final Selector sel) {
return wrapped.keyFor(sel);
}
public SelectionKey register(final Selector sel, final int ops, final Object att) throws ClosedChannelException {
return wrapped.register(sel, ops, att);
}
public SelectableChannel configureBlocking(final boolean block) throws IOException {
return wrapped.configureBlocking(block);
}
public boolean isBlocking() {
return wrapped.isBlocking();
}
public Object blockingLock() {
return wrapped.blockingLock();
}
public int write(final ByteBuffer src) throws IOException {
final int copy = Math.min(buffer.remaining(), src.remaining());
final int limit = src.limit();
src.limit(src.position()+copy);
buffer.put(src);
src.limit(limit);
if (!buffer.hasRemaining()) {
final int written = flushInternal();
if (written > 0 && src.hasRemaining()) {
return copy+write(src);
}
}
return copy;
}
private int flushInternal() throws IOException {
buffer.flip();
final int written = wrapped.write(buffer);
buffer.compact();
return written;
}
public boolean flush() throws IOException {
flushInternal();
return buffer.position() == 0;
}
protected void implCloseChannel() throws IOException {
if (!closed) {
closed = true;
try {
if (buffer.hasRemaining()) {
wrapped.configureBlocking(true);
while (buffer.position() != 0) {
flushInternal();
}
}
} catch (IllegalBlockingModeException e) {
// this happens when close is called asynchronously or something
// it's not a problem because we just want everything to die
} catch (Exception e) {
Throwables.propagateIfInstanceOf(e, IOException.class);
throw new IOException(e);
} finally {
wrapped.close();
}
}
}
}