org.apache.cxf.io.AbstractThresholdOutputStream 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.cxf.io;
import java.io.IOException;
import org.apache.cxf.helpers.LoadingByteArrayOutputStream;
/**
* Outputstream that will buffer a certain amount before writing anything to the underlying
* stream. When the threshold is reached, provides a callback point to allow the
* subclass to update headers, replace/set the output stream, etc...
*
* Also provides a callback for when the stream is closed without it reaching the threshold.
*/
public abstract class AbstractThresholdOutputStream extends AbstractWrappedOutputStream {
protected int threshold;
protected LoadingByteArrayOutputStream buffer;
public AbstractThresholdOutputStream(int threshold) {
this.threshold = threshold;
if (threshold >= 0) {
buffer = new LoadingByteArrayOutputStream(threshold + 1);
}
}
public abstract void thresholdReached() throws IOException;
public abstract void thresholdNotReached() throws IOException;
@Override
public void write(byte[] b, int off, int len) throws IOException {
if (buffer != null) {
int space = threshold - buffer.size();
if (space > len) {
space = len;
}
buffer.write(b, off, space);
len -= space;
off += space;
if (buffer.size() >= threshold) {
thresholdReached();
unBuffer();
}
if (len == 0) {
return;
}
}
super.write(b, off, len);
}
@Override
public void write(int b) throws IOException {
if (buffer != null) {
buffer.write(b);
if (buffer.size() >= threshold) {
thresholdReached();
unBuffer();
}
return;
}
super.write(b);
}
public void unBuffer() throws IOException {
if (buffer != null) {
if (buffer.size() > 0) {
super.write(buffer.getRawBytes(), 0, buffer.size());
}
buffer = null;
}
}
@Override
public void close() throws IOException {
if (buffer != null) {
thresholdNotReached();
unBuffer();
}
super.close();
}
}