/** | |
* 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.activemq.protobuf; | |
import java.io.EOFException; | |
import java.io.IOException; | |
import java.io.OutputStream; | |
/** | |
* Very similar to the java.io.ByteArrayOutputStream but this version | |
* is not thread safe and the resulting data is returned in a Buffer | |
* to avoid an extra byte[] allocation. It also does not re-grow it's | |
* internal buffer. | |
*/ | |
final public class BufferOutputStream extends OutputStream { | |
byte buffer[]; | |
int offset; | |
int limit; | |
int pos; | |
public BufferOutputStream(int size) { | |
this(new byte[size]); | |
} | |
public BufferOutputStream(byte[] buffer) { | |
this.buffer = buffer; | |
this.limit = buffer.length; | |
} | |
public BufferOutputStream(Buffer data) { | |
this.buffer = data.data; | |
this.pos = this.offset = data.offset; | |
this.limit = data.offset+data.length; | |
} | |
public void write(int b) throws IOException { | |
int newPos = pos + 1; | |
checkCapacity(newPos); | |
buffer[pos] = (byte) b; | |
pos = newPos; | |
} | |
public void write(byte b[], int off, int len) throws IOException { | |
int newPos = pos + len; | |
checkCapacity(newPos); | |
System.arraycopy(b, off, buffer, pos, len); | |
pos = newPos; | |
} | |
public Buffer getNextBuffer(int len) throws IOException { | |
int newPos = pos + len; | |
checkCapacity(newPos); | |
return new Buffer(buffer, pos, len); | |
} | |
/** | |
* Ensures the the buffer has at least the minimumCapacity specified. | |
* @param i | |
* @throws EOFException | |
*/ | |
private void checkCapacity(int minimumCapacity) throws IOException { | |
if( minimumCapacity > limit ) { | |
throw new EOFException("Buffer limit reached."); | |
} | |
} | |
public void reset() { | |
pos = offset; | |
} | |
public Buffer toBuffer() { | |
return new Buffer(buffer, offset, pos); | |
} | |
public byte[] toByteArray() { | |
return toBuffer().toByteArray(); | |
} | |
public int size() { | |
return offset-pos; | |
} | |
} |