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* 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 * | |
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package org.apache.james.mime4j.io; | |
import java.io.InputStream; | |
import java.io.IOException; | |
public class PartialInputStream extends PositionInputStream { | |
private final long limit; | |
public PartialInputStream(InputStream inputStream, long offset, long length) throws IOException { | |
super(inputStream); | |
inputStream.skip(offset); | |
this.limit = offset + length; | |
} | |
public int available() throws IOException { | |
return Math.min(super.available(), getBytesLeft()); | |
} | |
public int read() throws IOException { | |
if (limit > position) | |
return super.read(); | |
else | |
return -1; | |
} | |
public int read(byte b[], int off, int len) throws IOException { | |
len = Math.min(len, getBytesLeft()); | |
return super.read(b, off, len); | |
} | |
public long skip(long n) throws IOException { | |
n = Math.min(n, getBytesLeft()); | |
return super.skip(n); | |
} | |
private int getBytesLeft() { | |
return (int)Math.min(Integer.MAX_VALUE, limit - position); | |
} | |
} |