org.apache.xmlgraphics.image.loader.util.ImageInputStreamAdapter 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.
*/
/* $Id: ImageInputStreamAdapter.java 750418 2009-03-05 11:03:54Z vhennebert $ */
package org.apache.xmlgraphics.image.loader.util;
import java.io.IOException;
import java.io.InputStream;
import javax.imageio.stream.ImageInputStream;
/**
* Decorates an ImageInputStream with an InputStream interface. The methods mark()
* and reset() are fully supported. The method available() will
* always return 0.
*/
public class ImageInputStreamAdapter extends InputStream {
private ImageInputStream iin;
private long lastMarkPosition;
/**
* Creates a new ImageInputStreamAdapter.
* @param iin the underlying ImageInputStream
*/
public ImageInputStreamAdapter(ImageInputStream iin) {
assert iin != null : "InputStream is null";
this.iin = iin;
}
/** {@inheritDoc} */
public int read(byte[] b, int off, int len) throws IOException {
return iin.read(b, off, len);
}
/** {@inheritDoc} */
public int read(byte[] b) throws IOException {
return iin.read(b);
}
/** {@inheritDoc} */
public int read() throws IOException {
return iin.read();
}
/** {@inheritDoc} */
public long skip(long n) throws IOException {
return iin.skipBytes(n);
}
/** {@inheritDoc} */
public void close() throws IOException {
iin.close();
iin = null;
}
/** {@inheritDoc} */
public synchronized void mark(int readlimit) {
//Parameter readlimit is ignored
try {
//Cannot use mark()/reset() since they are nestable, and InputStream's are not
this.lastMarkPosition = iin.getStreamPosition();
} catch (IOException ioe) {
throw new RuntimeException(
"Unexpected IOException in ImageInputStream.getStreamPosition()", ioe);
}
}
/** {@inheritDoc} */
public boolean markSupported() {
return true;
}
/** {@inheritDoc} */
public synchronized void reset() throws IOException {
iin.seek(this.lastMarkPosition);
}
/** {@inheritDoc} */
public int available() throws IOException {
return 0;
}
}