org.apache.pdfbox.io.IOUtils Maven / Gradle / Ivy
Show all versions of pdfbox Show documentation
/*
* 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.
*/
/* $Id: IOUtils.java 1834594 2018-06-28 10:29:51Z msahyoun $ */
package org.apache.pdfbox.io;
import java.io.ByteArrayOutputStream;
import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.commons.logging.Log;
/**
* This class contains various I/O-related methods.
*/
public final class IOUtils
{
//TODO PDFBox should really use Apache Commons IO.
private IOUtils()
{
//Utility class. Don't instantiate.
}
/**
* Reads the input stream and returns its contents as a byte array.
* @param in the input stream to read from.
* @return the byte array
* @throws IOException if an I/O error occurs
*/
public static byte[] toByteArray(InputStream in) throws IOException
{
ByteArrayOutputStream baout = new ByteArrayOutputStream();
copy(in, baout);
return baout.toByteArray();
}
/**
* Copies all the contents from the given input stream to the given output stream.
* @param input the input stream
* @param output the output stream
* @return the number of bytes that have been copied
* @throws IOException if an I/O error occurs
*/
public static long copy(InputStream input, OutputStream output) throws IOException
{
byte[] buffer = new byte[4096];
long count = 0;
int n = 0;
while (-1 != (n = input.read(buffer)))
{
output.write(buffer, 0, n);
count += n;
}
return count;
}
/**
* Populates the given buffer with data read from the input stream. If the data doesn't
* fit the buffer, only the data that fits in the buffer is read. If the data is less than
* fits in the buffer, the buffer is not completely filled.
* @param in the input stream to read from
* @param buffer the buffer to fill
* @return the number of bytes written to the buffer
* @throws IOException if an I/O error occurs
*/
public static long populateBuffer(InputStream in, byte[] buffer) throws IOException
{
int remaining = buffer.length;
while (remaining > 0)
{
int bufferWritePos = buffer.length - remaining;
int bytesRead = in.read(buffer, bufferWritePos, remaining);
if (bytesRead < 0)
{
break; //EOD
}
remaining -= bytesRead;
}
return buffer.length - remaining;
}
/**
* Null safe close of the given {@link Closeable} suppressing any exception.
*
* @param closeable to be closed
*/
public static void closeQuietly(Closeable closeable)
{
try
{
if (closeable != null)
{
closeable.close();
}
}
catch (IOException ioe)
{
// ignore
}
}
/**
* Try to close an IO resource and log and return if there was an exception.
*
* An exception is only returned if the IOException passed in is null.
*
* @param closeable to be closed
* @param logger the logger to be used so that logging appears under that log instance
* @param resourceName the name to appear in the log output
* @param initialException to be closed
* @return the IOException is there was any but only if initialException is null
*/
public static IOException closeAndLogException(Closeable closeable, Log logger, String resourceName, IOException initialException)
{
try
{
closeable.close();
}
catch (IOException ioe)
{
logger.warn("Error closing " + resourceName, ioe);
if (initialException == null)
{
return ioe;
}
}
return initialException;
}
}