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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.zeroturnaround.zip.commons;
import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.Reader;
import java.io.StringWriter;
import java.io.Writer;
/**
* This is a class that has been made significantly smaller (deleted a bunch of methods) and originally
* is from the Apache commons-io package. All license and other documentation is intact.
*
* General IO stream manipulation utilities.
*
* This class provides static utility methods for input/output operations.
*
* - closeQuietly - these methods close a stream ignoring nulls and exceptions
*
- toXxx/read - these methods read data from a stream
*
- write - these methods write data to a stream
*
- copy - these methods copy all the data from one stream to another
*
- contentEquals - these methods compare the content of two streams
*
*
* The byte-to-char methods and char-to-byte methods involve a conversion step. Two methods are provided in each case, one that uses the platform default encoding and the other
* which allows you to specify an encoding. You are encouraged to always specify an encoding because relying on the platform default can lead to unexpected results, for example
* when moving from development to production.
*
* All the methods in this class that read a stream are buffered internally. This means that there is no cause to use a BufferedInputStream or
* BufferedReader. The default buffer size of 4K has been shown to be efficient in tests.
*
* Wherever possible, the methods in this class do not flush or close the stream. This is to avoid making non-portable assumptions about the streams' origin and further
* use. Thus the caller is still responsible for closing streams after use.
*
* Origin of code: Excalibur.
*
* @author Peter Donald
* @author Jeff Turner
* @author Matthew Hawthorne
* @author Stephen Colebourne
* @author Gareth Davis
* @author Ian Springer
* @author Niall Pemberton
* @author Sandy McArthur
* @version $Id: IOUtils.java 481854 2006-12-03 18:30:07Z scolebourne $
*/
public class IOUtils {
// NOTE: This class is focused on InputStream, OutputStream, Reader and
// Writer. Each method should take at least one of these as a parameter,
// or return one of them.
/**
* The Unix directory separator character.
*/
public static final char DIR_SEPARATOR_UNIX = '/';
/**
* The Windows directory separator character.
*/
public static final char DIR_SEPARATOR_WINDOWS = '\\';
/**
* The system directory separator character.
*/
public static final char DIR_SEPARATOR = File.separatorChar;
/**
* The Unix line separator string.
*/
public static final String LINE_SEPARATOR_UNIX = "\n";
/**
* The Windows line separator string.
*/
public static final String LINE_SEPARATOR_WINDOWS = "\r\n";
/**
* The system line separator string.
*/
public static final String LINE_SEPARATOR;
static {
// avoid security issues
StringWriter buf = new StringWriter(4);
PrintWriter out = new PrintWriter(buf);
out.println();
LINE_SEPARATOR = buf.toString();
}
/**
* The default buffer size to use.
*/
private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;
/**
* Instances should NOT be constructed in standard programming.
*/
public IOUtils() {
super();
}
/**
* Unconditionally close an InputStream.
*
* Equivalent to {@link InputStream#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
*
* @param input the InputStream to close, may be null or already closed
*/
public static void closeQuietly(InputStream input) {
try {
if (input != null) {
input.close();
}
}
catch (IOException ioe) {
// ignore
}
}
/**
* Unconditionally close an OutputStream.
*
* Equivalent to {@link OutputStream#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
*
* @param output the OutputStream to close, may be null or already closed
*/
public static void closeQuietly(OutputStream output) {
try {
if (output != null) {
output.close();
}
}
catch (IOException ioe) {
// ignore
}
}
// read toByteArray
// -----------------------------------------------------------------------
/**
* Get the contents of an InputStream as a byte[].
*
* This method buffers the input internally, so there is no need to use a BufferedInputStream.
*
* @param input the InputStream to read from
* @return the requested byte array
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
*/
public static byte[] toByteArray(InputStream input) throws IOException {
ByteArrayOutputStream output = new ByteArrayOutputStream();
copy(input, output);
return output.toByteArray();
}
/**
* Get the contents of an InputStream as a String
* using the specified character encoding.
*
* Character encoding names can be found at IANA.
*
* This method buffers the input internally, so there is no need to use a BufferedInputStream.
*
* @param input the InputStream to read from
* @param encoding the encoding to use, null means platform default
* @return the requested String
* @throws NullPointerException if the input is null
* @throws IOException if an I/O error occurs
*/
public static String toString(InputStream input, String encoding)
throws IOException {
StringWriter sw = new StringWriter();
copy(input, sw, encoding);
return sw.toString();
}
// copy from InputStream
// -----------------------------------------------------------------------
/**
* Copy bytes from an InputStream to an OutputStream.
*
* This method buffers the input internally, so there is no need to use a BufferedInputStream.
*
* Large streams (over 2GB) will return a bytes copied value of -1 after the copy has completed since the correct number of bytes cannot be returned as an int. For
* large streams use the copyLarge(InputStream, OutputStream) method.
*
* @param input the InputStream to read from
* @param output the OutputStream to write to
* @return the number of bytes copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @throws ArithmeticException if the byte count is too large
* @since Commons IO 1.1
*/
public static int copy(InputStream input, OutputStream output) throws IOException {
long count = copyLarge(input, output);
if (count > Integer.MAX_VALUE) {
return -1;
}
return (int) count;
}
/**
* Copy bytes from a large (over 2GB) InputStream to an OutputStream.
*
* This method buffers the input internally, so there is no need to use a BufferedInputStream.
*
* @param input the InputStream to read from
* @param output the OutputStream to write to
* @return the number of bytes copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since Commons IO 1.3
*/
public static long copyLarge(InputStream input, OutputStream output)
throws IOException {
byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
long count = 0;
int n = 0;
while (-1 != (n = input.read(buffer))) {
output.write(buffer, 0, n);
count += n;
}
return count;
}
/**
* Copy bytes from an InputStream to chars on a Writer using the default character encoding of the platform.
*
* This method buffers the input internally, so there is no need to use a BufferedInputStream.
*
* This method uses {@link InputStreamReader}.
*
* @param input the InputStream to read from
* @param output the Writer to write to
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since Commons IO 1.1
*/
public static void copy(InputStream input, Writer output)
throws IOException {
InputStreamReader in = new InputStreamReader(input);
copy(in, output);
}
/**
* Copy bytes from an InputStream to chars on a Writer using the specified character encoding.
*
* This method buffers the input internally, so there is no need to use a BufferedInputStream.
*
* Character encoding names can be found at IANA.
*
* This method uses {@link InputStreamReader}.
*
* @param input the InputStream to read from
* @param output the Writer to write to
* @param encoding the encoding to use, null means platform default
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since Commons IO 1.1
*/
public static void copy(InputStream input, Writer output, String encoding)
throws IOException {
if (encoding == null) {
copy(input, output);
}
else {
InputStreamReader in = new InputStreamReader(input, encoding);
copy(in, output);
}
}
// copy from Reader
// -----------------------------------------------------------------------
/**
* Copy chars from a Reader to a Writer.
*
* This method buffers the input internally, so there is no need to use a BufferedReader.
*
* Large streams (over 2GB) will return a chars copied value of -1 after the copy has completed since the correct number of chars cannot be returned as an int. For
* large streams use the copyLarge(Reader, Writer) method.
*
* @param input the Reader to read from
* @param output the Writer to write to
* @return the number of characters copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @throws ArithmeticException if the character count is too large
* @since Commons IO 1.1
*/
public static int copy(Reader input, Writer output) throws IOException {
long count = copyLarge(input, output);
if (count > Integer.MAX_VALUE) {
return -1;
}
return (int) count;
}
/**
* Copy chars from a large (over 2GB) Reader to a Writer.
*
* This method buffers the input internally, so there is no need to use a BufferedReader.
*
* @param input the Reader to read from
* @param output the Writer to write to
* @return the number of characters copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since Commons IO 1.3
*/
public static long copyLarge(Reader input, Writer output) throws IOException {
char[] buffer = new char[DEFAULT_BUFFER_SIZE];
long count = 0;
int n = 0;
while (-1 != (n = input.read(buffer))) {
output.write(buffer, 0, n);
count += n;
}
return count;
}
// content equals
// -----------------------------------------------------------------------
/**
* Compare the contents of two Streams to determine if they are equal or
* not.
*
* This method buffers the input internally using BufferedInputStream if they are not already buffered.
*
* @param input1 the first stream
* @param input2 the second stream
* @return true if the content of the streams are equal or they both don't
* exist, false otherwise
* @throws NullPointerException if either input is null
* @throws IOException if an I/O error occurs
*/
public static boolean contentEquals(InputStream input1, InputStream input2)
throws IOException {
if (!(input1 instanceof BufferedInputStream)) {
input1 = new BufferedInputStream(input1);
}
if (!(input2 instanceof BufferedInputStream)) {
input2 = new BufferedInputStream(input2);
}
int ch = input1.read();
while (-1 != ch) {
int ch2 = input2.read();
if (ch != ch2) {
return false;
}
ch = input1.read();
}
int ch2 = input2.read();
return (ch2 == -1);
}
}