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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 com.parse;
import java.io.ByteArrayOutputStream;
import java.io.Closeable;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
/**
* General IO stream manipulation utilities.
*/
/** package */ class ParseIOUtils {
private static final int EOF = -1;
/**
* The default buffer size ({@value}) to use for
* {@link #copyLarge(InputStream, OutputStream)}
*/
private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;
/**
* The default buffer size to use for the skip() methods.
*/
private static final int SKIP_BUFFER_SIZE = 2048;
// Allocated in the relevant skip method if necessary.
/*
* N.B. no need to synchronize these because:
* - we don't care if the buffer is created multiple times (the data is ignored)
* - we always use the same size buffer, so if it it is recreated it will still be OK
* (if the buffer size were variable, we would need to synch. to ensure some other thread
* did not create a smaller one)
*/
private static byte[] SKIP_BYTE_BUFFER;
// 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();
}
// 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, or -1 if > Integer.MAX_VALUE
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 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.
*
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
*
* @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 1.3
*/
public static long copyLarge(InputStream input, OutputStream output)
throws IOException {
return copyLarge(input, output, new byte[DEFAULT_BUFFER_SIZE]);
}
/**
* Copy bytes from a large (over 2GB) InputStream to an
* OutputStream.
*
* This method uses the provided buffer, so there is no need to use a
* BufferedInputStream.
*
*
* @param input the InputStream to read from
* @param output the OutputStream to write to
* @param buffer the buffer to use for the copy
* @return the number of bytes copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.2
*/
public static long copyLarge(InputStream input, OutputStream output, byte[] buffer)
throws IOException {
long count = 0;
int n = 0;
while (EOF != (n = input.read(buffer))) {
output.write(buffer, 0, n);
count += n;
}
return count;
}
/**
* Copy some or all bytes from a large (over 2GB) InputStream to an
* OutputStream, optionally skipping input bytes.
*
* This method buffers the input internally, so there is no need to use a
* BufferedInputStream.
*
* The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
*
* @param input the InputStream to read from
* @param output the OutputStream to write to
* @param inputOffset : number of bytes to skip from input before copying
* -ve values are ignored
* @param length : number of bytes to copy. -ve means all
* @return the number of bytes copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.2
*/
public static long copyLarge(InputStream input, OutputStream output, long inputOffset, long length)
throws IOException {
return copyLarge(input, output, inputOffset, length, new byte[DEFAULT_BUFFER_SIZE]);
}
/**
* Skip bytes from an input byte stream.
* This implementation guarantees that it will read as many bytes
* as possible before giving up; this may not always be the case for
* subclasses of {@link java.io.Reader}.
*
* @param input byte stream to skip
* @param toSkip number of bytes to skip.
* @return number of bytes actually skipped.
*
* @see InputStream#skip(long)
*
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if toSkip is negative
* @since 2.0
*/
public static long skip(InputStream input, long toSkip) throws IOException {
if (toSkip < 0) {
throw new IllegalArgumentException("Skip count must be non-negative, actual: " + toSkip);
}
/*
* N.B. no need to synchronize this because: - we don't care if the buffer is created multiple times (the data
* is ignored) - we always use the same size buffer, so if it it is recreated it will still be OK (if the buffer
* size were variable, we would need to synch. to ensure some other thread did not create a smaller one)
*/
if (SKIP_BYTE_BUFFER == null) {
SKIP_BYTE_BUFFER = new byte[SKIP_BUFFER_SIZE];
}
long remain = toSkip;
while (remain > 0) {
long n = input.read(SKIP_BYTE_BUFFER, 0, (int) Math.min(remain, SKIP_BUFFER_SIZE));
if (n < 0) { // EOF
break;
}
remain -= n;
}
return toSkip - remain;
}
/**
* Copy some or all bytes from a large (over 2GB) InputStream to an
* OutputStream, optionally skipping input bytes.
*
* This method uses the provided buffer, so there is no need to use a
* BufferedInputStream.
*
*
* @param input the InputStream to read from
* @param output the OutputStream to write to
* @param inputOffset : number of bytes to skip from input before copying
* -ve values are ignored
* @param length : number of bytes to copy. -ve means all
* @param buffer the buffer to use for the copy
*
* @return the number of bytes copied
* @throws NullPointerException if the input or output is null
* @throws IOException if an I/O error occurs
* @since 2.2
*/
public static long copyLarge(InputStream input, OutputStream output,
final long inputOffset, final long length, byte[] buffer) throws IOException {
if (inputOffset > 0) {
skipFully(input, inputOffset);
}
if (length == 0) {
return 0;
}
final int bufferLength = buffer.length;
int bytesToRead = bufferLength;
if (length > 0 && length < bufferLength) {
bytesToRead = (int) length;
}
int read;
long totalRead = 0;
while (bytesToRead > 0 && EOF != (read = input.read(buffer, 0, bytesToRead))) {
output.write(buffer, 0, read);
totalRead += read;
if (length > 0) { // only adjust length if not reading to the end
// Note the cast must work because buffer.length is an integer
bytesToRead = (int) Math.min(length - totalRead, bufferLength);
}
}
return totalRead;
}
/**
* Skip the requested number of bytes or fail if there are not enough left.
*
* This allows for the possibility that {@link InputStream#skip(long)} may
* not skip as many bytes as requested (most likely because of reaching EOF).
*
* @param input stream to skip
* @param toSkip the number of bytes to skip
* @see InputStream#skip(long)
*
* @throws IOException if there is a problem reading the file
* @throws IllegalArgumentException if toSkip is negative
* @throws EOFException if the number of bytes skipped was incorrect
* @since 2.0
*/
public static void skipFully(InputStream input, long toSkip) throws IOException {
if (toSkip < 0) {
throw new IllegalArgumentException("Bytes to skip must not be negative: " + toSkip);
}
long skipped = skip(input, toSkip);
if (skipped != toSkip) {
throw new EOFException("Bytes to skip: " + toSkip + " actual: " + skipped);
}
}
/**
* 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
}
}
/**
* Closes a Closeable unconditionally.
*
* Equivalent to {@link Closeable#close()}, except any exceptions will be ignored.
* This is typically used in finally blocks.
*
* Example code:
*
* Closeable closeable = null;
* try {
* closeable = new FileReader("foo.txt");
* // process closeable
* closeable.close();
* } catch (Exception e) {
* // error handling
* } finally {
* IOUtils.closeQuietly(closeable);
* }
*
*
* @param closeable the object to close, may be null or already closed
* @since 2.0
*/
public static void closeQuietly(final Closeable closeable) {
try {
if (closeable != null) {
closeable.close();
}
} catch (final IOException ioe) {
// ignore
}
}
}