org.apache.sshd.common.util.io.NullOutputStream Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.sshd.common.util.io;
import java.io.EOFException;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.channels.Channel;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* A {code /dev/null} output stream
*
* @author Apache MINA SSHD Project
*/
public class NullOutputStream extends OutputStream implements Channel {
private final AtomicBoolean open = new AtomicBoolean(true);
public NullOutputStream() {
super();
}
@Override
public boolean isOpen() {
return open.get();
}
@Override
public void write(int b) throws IOException {
if (!isOpen()) {
throw new EOFException("Stream is closed for writing one byte");
}
}
@Override
public void write(byte[] b, int off, int len) throws IOException {
if (!isOpen()) {
throw new EOFException("Stream is closed for writing " + len + " bytes");
}
}
@Override
public void flush() throws IOException {
if (!isOpen()) {
throw new EOFException("Stream is closed for flushing");
}
}
@Override
public void close() throws IOException {
if (open.getAndSet(false)) {
// noinspection UnnecessaryReturnStatement
return; // debug breakpoint
}
}
}