org.apache.commons.compress.utils.ArchiveUtils Maven / Gradle / Ivy
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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 "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 org.apache.commons.compress.utils;
import java.io.UnsupportedEncodingException;
import org.apache.commons.compress.archivers.ArchiveEntry;
/**
* Generic Archive utilities
*/
public class ArchiveUtils {
/** Private constructor to prevent instantiation of this utility class. */
private ArchiveUtils(){
}
/**
* Generates a string containing the name, isDirectory setting and size of an entry.
*
* For example:
* - 2000 main.c
* d 100 testfiles
*
* @return the representation of the entry
*/
public static String toString(ArchiveEntry entry){
StringBuffer sb = new StringBuffer();
sb.append(entry.isDirectory()? 'd' : '-');// c.f. "ls -l" output
String size = Long.toString((entry.getSize()));
sb.append(' ');
// Pad output to 7 places, leading spaces
for(int i=7; i > size.length(); i--){
sb.append(' ');
}
sb.append(size);
sb.append(' ').append(entry.getName());
return sb.toString();
}
/**
* Check if buffer contents matches Ascii String.
*
* @param expected
* @param buffer
* @param offset
* @param length
* @return {@code true} if buffer is the same as the expected string
*/
public static boolean matchAsciiBuffer(
String expected, byte[] buffer, int offset, int length){
byte[] buffer1;
try {
buffer1 = expected.getBytes("ASCII");
} catch (UnsupportedEncodingException e) {
throw new RuntimeException(e); // Should not happen
}
return isEqual(buffer1, 0, buffer1.length, buffer, offset, length, false);
}
/**
* Check if buffer contents matches Ascii String.
*
* @param expected
* @param buffer
* @return {@code true} if buffer is the same as the expected string
*/
public static boolean matchAsciiBuffer(String expected, byte[] buffer){
return matchAsciiBuffer(expected, buffer, 0, buffer.length);
}
/**
* Convert a string to Ascii bytes.
* Used for comparing "magic" strings which need to be independent of the default Locale.
*
* @param inputString
* @return the bytes
*/
public static byte[] toAsciiBytes(String inputString){
try {
return inputString.getBytes("ASCII");
} catch (UnsupportedEncodingException e) {
throw new RuntimeException(e); // Should never happen
}
}
/**
* Convert an input byte array to a String using the ASCII character set.
*
* @param inputBytes
* @return the bytes, interpreted as an Ascii string
*/
public static String toAsciiString(final byte[] inputBytes){
try {
return new String(inputBytes, "ASCII");
} catch (UnsupportedEncodingException e) {
throw new RuntimeException(e); // Should never happen
}
}
/**
* Convert an input byte array to a String using the ASCII character set.
*
* @param inputBytes input byte array
* @param offset offset within array
* @param length length of array
* @return the bytes, interpreted as an Ascii string
*/
public static String toAsciiString(final byte[] inputBytes, int offset, int length){
try {
return new String(inputBytes, offset, length, "ASCII");
} catch (UnsupportedEncodingException e) {
throw new RuntimeException(e); // Should never happen
}
}
/**
* Compare byte buffers, optionally ignoring trailing nulls
*
* @param buffer1
* @param offset1
* @param length1
* @param buffer2
* @param offset2
* @param length2
* @param ignoreTrailingNulls
* @return {@code true} if buffer1 and buffer2 have same contents, having regard to trailing nulls
*/
public static boolean isEqual(
final byte[] buffer1, final int offset1, final int length1,
final byte[] buffer2, final int offset2, final int length2,
boolean ignoreTrailingNulls){
int minLen=length1 < length2 ? length1 : length2;
for (int i=0; i < minLen; i++){
if (buffer1[offset1+i] != buffer2[offset2+i]){
return false;
}
}
if (length1 == length2){
return true;
}
if (ignoreTrailingNulls){
if (length1 > length2){
for(int i = length2; i < length1; i++){
if (buffer1[offset1+i] != 0){
return false;
}
}
} else {
for(int i = length1; i < length2; i++){
if (buffer2[offset2+i] != 0){
return false;
}
}
}
return true;
}
return false;
}
/**
* Compare byte buffers
*
* @param buffer1
* @param offset1
* @param length1
* @param buffer2
* @param offset2
* @param length2
* @return {@code true} if buffer1 and buffer2 have same contents
*/
public static boolean isEqual(
final byte[] buffer1, final int offset1, final int length1,
final byte[] buffer2, final int offset2, final int length2){
return isEqual(buffer1, offset1, length1, buffer2, offset2, length2, false);
}
/**
* Compare byte buffers
*
* @param buffer1
* @param buffer2
* @return {@code true} if buffer1 and buffer2 have same contents
*/
public static boolean isEqual(final byte[] buffer1, final byte[] buffer2 ){
return isEqual(buffer1, 0, buffer1.length, buffer2, 0, buffer2.length, false);
}
/**
* Compare byte buffers, optionally ignoring trailing nulls
*
* @param buffer1
* @param buffer2
* @param ignoreTrailingNulls
* @return {@code true} if buffer1 and buffer2 have same contents
*/
public static boolean isEqual(final byte[] buffer1, final byte[] buffer2, boolean ignoreTrailingNulls){
return isEqual(buffer1, 0, buffer1.length, buffer2, 0, buffer2.length, ignoreTrailingNulls);
}
/**
* Compare byte buffers, ignoring trailing nulls
*
* @param buffer1
* @param offset1
* @param length1
* @param buffer2
* @param offset2
* @param length2
* @return {@code true} if buffer1 and buffer2 have same contents, having regard to trailing nulls
*/
public static boolean isEqualWithNull(
final byte[] buffer1, final int offset1, final int length1,
final byte[] buffer2, final int offset2, final int length2){
return isEqual(buffer1, offset1, length1, buffer2, offset2, length2, true);
}
}