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* Copyright 2003-2007 Luck Consulting Pty Ltd
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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package net.sf.ehcache.util;
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import java.io.ByteArrayOutputStream;
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import java.io.IOException;
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import java.io.ObjectOutputStream;
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import java.io.Serializable;
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* This class is designed to minimise the number of System.arraycopy(); methods
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* required to complete.
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* ByteArrayOutputStream in the JDK is tuned for a wide variety of purposes. This sub-class
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* starts with an initial size which is a closer match for ehcache usage.
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* @author <a href="mailto:gluck@gregluck.com">Greg Luck</a>
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public final class MemoryEfficientByteArrayOutputStream extends ByteArrayOutputStream {
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* byte[] payloads are not expected to be tiny.
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private static final int BEST_GUESS_SIZE = 512;
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private static int lastSize = BEST_GUESS_SIZE;
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* Creates a new byte array output stream, with a buffer capacity of
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* the specified size, in bytes.
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* @param size the initial size.
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public MemoryEfficientByteArrayOutputStream(int size) {
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* Gets the bytes. Not all may be valid. Use only up to getSize()
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* @return the underlying byte[]
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public synchronized byte getBytes()[] {
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* @param serializable any Object that implements Serializable
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* @param estimatedPayloadSize how many bytes is expected to be in the Serialized representation
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* @return a ByteArrayOutputStream with a Serialized object in it
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* @throws java.io.IOException if something goes wrong with the Serialization
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public static MemoryEfficientByteArrayOutputStream serialize(Serializable serializable, int estimatedPayloadSize) throws IOException {
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MemoryEfficientByteArrayOutputStream outstr = new MemoryEfficientByteArrayOutputStream(estimatedPayloadSize);
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ObjectOutputStream objstr = new ObjectOutputStream(outstr);
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objstr.writeObject(serializable);
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* Factory method. This method optimises memory by trying to make a better guess than the Java default
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* of 32 bytes by assuming the starting point for the serialized size will be what it was last time
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* this method was called.
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* @param serializable any Object that implements Serializable
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* @return a ByteArrayOutputStream with a Serialized object in it
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* @throws java.io.IOException if something goes wrong with the Serialization
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public static MemoryEfficientByteArrayOutputStream serialize(Serializable serializable) throws IOException {
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MemoryEfficientByteArrayOutputStream outstr = new MemoryEfficientByteArrayOutputStream(lastSize);
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ObjectOutputStream objstr = new ObjectOutputStream(outstr);
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objstr.writeObject(serializable);
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lastSize = outstr.getBytes().length;
added
removed
net/sf/ehcache/util/MemoryEfficientByteArrayOutputStream.java
