com.alipay.sofa.ark.loader.jar.ZipInflaterInputStream 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.
*/
package com.alipay.sofa.ark.loader.jar;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.util.zip.Inflater;
import java.util.zip.InflaterInputStream;
/**
* {@link InflaterInputStream} that supports the writing of an extra "dummy" byte (which
* is required with JDK 6) and returns accurate available() results.
*
* @author Phillip Webb
*/
public class ZipInflaterInputStream extends InflaterInputStream {
private boolean extraBytesWritten;
private int available;
ZipInflaterInputStream(InputStream inputStream, int size) {
super(inputStream, new Inflater(true), getInflaterBufferSize(size));
this.available = size;
}
@Override
public int available() throws IOException {
if (this.available < 0) {
return super.available();
}
return this.available;
}
@Override
public int read(byte[] b, int off, int len) throws IOException {
int result = super.read(b, off, len);
if (result != -1) {
this.available -= result;
}
return result;
}
@Override
public void close() throws IOException {
super.close();
this.inf.end();
}
@Override
protected void fill() throws IOException {
try {
super.fill();
} catch (EOFException ex) {
if (this.extraBytesWritten) {
throw ex;
}
this.len = 1;
this.buf[0] = 0x0;
this.extraBytesWritten = true;
this.inf.setInput(this.buf, 0, this.len);
}
}
private static int getInflaterBufferSize(long size) {
// inflater likes some space
size += 2;
size = (size > 65536 ? 8192 : size);
size = (size <= 0 ? 4096 : size);
return (int) size;
}
}