replicant-frameworks_native/awt/javax/imageio/stream/MemoryCacheImageOutputStream.java
The Android Open Source Project 7c1b96a165 Initial Contribution
2008-10-21 07:00:00 -07:00

131 lines
3.3 KiB
Java

/*
* 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 javax.imageio.stream;
import org.apache.harmony.x.imageio.stream.RandomAccessMemoryCache;
import java.io.OutputStream;
import java.io.IOException;
/**
* The MemoryCacheImageOutputStream class implements ImageOutputStream
* using a memory buffer for caching the data.
*/
public class MemoryCacheImageOutputStream extends ImageOutputStreamImpl {
/** The os. */
OutputStream os;
/** The ramc. */
RandomAccessMemoryCache ramc = new RandomAccessMemoryCache();
/**
* Instantiates a new MemoryCacheImageOutputStream
* which writes to the specified OutputStream.
*
* @param stream the OutputStream.
*/
public MemoryCacheImageOutputStream(OutputStream stream) {
if (stream == null) {
throw new IllegalArgumentException("stream == null!");
}
os = stream;
}
@Override
public void write(int b) throws IOException {
flushBits(); // See the flushBits method description
ramc.putData(b, streamPos);
streamPos++;
}
@Override
public void write(byte[] b, int off, int len) throws IOException {
flushBits(); // See the flushBits method description
ramc.putData(b, off, len, streamPos);
streamPos += len;
}
@Override
public int read() throws IOException {
bitOffset = 0;
int res = ramc.getData(streamPos);
if (res >= 0) {
streamPos++;
}
return res;
}
@Override
public int read(byte[] b, int off, int len) throws IOException {
bitOffset = 0;
int res = ramc.getData(b, off, len, streamPos);
if (res > 0) {
streamPos += res;
}
return res;
}
@Override
public long length() {
return ramc.length();
}
@Override
public boolean isCached() {
return true;
}
@Override
public boolean isCachedMemory() {
return true;
}
@Override
public boolean isCachedFile() {
return false;
}
@Override
public void close() throws IOException {
flushBefore(length());
super.close();
ramc.close();
}
@Override
public void flushBefore(long pos) throws IOException {
long flushedPosition = getFlushedPosition();
super.flushBefore(pos);
long newFlushedPosition = getFlushedPosition();
int nBytes = (int)(newFlushedPosition - flushedPosition);
ramc.getData(os, nBytes, flushedPosition);
ramc.freeBefore(newFlushedPosition);
os.flush();
}
}