com.alipay.sofa.ark.loader.jar.Bytes 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 com.alipay.sofa.ark.loader.data.RandomAccessData;
import com.alipay.sofa.ark.loader.data.RandomAccessData.ResourceAccess;
import java.io.IOException;
import java.io.InputStream;
/**
* Utilities for dealing with bytes from ZIP files.
*
* @author Phillip Webb
*/
final public class Bytes {
private static final byte[] EMPTY_BYTES = new byte[] {};
private Bytes() {
}
public static byte[] get(RandomAccessData data) throws IOException {
InputStream inputStream = data.getInputStream(ResourceAccess.ONCE);
try {
return get(inputStream, data.getSize());
} finally {
inputStream.close();
}
}
public static byte[] get(InputStream inputStream, long length) throws IOException {
if (length == 0) {
return EMPTY_BYTES;
}
byte[] bytes = new byte[(int) length];
if (!fill(inputStream, bytes)) {
throw new IOException("Unable to read bytes");
}
return bytes;
}
public static boolean fill(InputStream inputStream, byte[] bytes) throws IOException {
return fill(inputStream, bytes, 0, bytes.length);
}
private static boolean fill(InputStream inputStream, byte[] bytes, int offset, int length)
throws IOException {
while (length > 0) {
int read = inputStream.read(bytes, offset, length);
if (read == -1) {
return false;
}
offset += read;
length = -read;
}
return true;
}
public static long littleEndianValue(byte[] bytes, int offset, int length) {
long value = 0;
for (int i = length - 1; i >= 0; i--) {
value = ((value << 8) | (bytes[offset + i] & 0xFF));
}
return value;
}
}