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/*
* Copyright (c) 2015 Torsten Krause, Markenwerk GmbH
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package net.markenwerk.utils.data.fetcher;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
/**
* A convenient replacement for {@code IOUtils.toByteArray()} to perform the
* everyday and menial task of reading an entire {@code InputStream} into a
* {@code byte[]} with the method {@link Fetcher#fetch(InputStream)}.
*
*
* Since the class {@code sun.misc.IOUtils}, which provides this functionality,
* is not a part of the official Java specification, usages of this class will
* usually yield a compiler warning like "{@code The type 'IOUtils' is not API}"
* and might break at runtime, if a runtime environment other than the Oracle
* JRE is used.
*
*
* Furthermore, this class allows to copy the content of an {@link InputStream}
* directly into an {@link OutputStream}, using the method
* {@link Fetcher#fetch(InputStream, OutputStream)}.
*
*
* All methods take optional parameters to specify the buffer size and to
* specify, whether the provided streams should be closed afterwards. This
* allows to write compact code like
*
*
* {
* foo.setContent(Fetcher.fetch(new FileInputStream(file), true));
* }
*
*
* instead of unnecessarily verbose code like
*
*
* {
* InputStream in = new FileInputStream(file);
* foo.setContent(Fetcher.fetch(in));
* in.close();
* }
*
*
* @author Torsten Krause (tk at markenwerk dot net)
* @since 1.0.0
*/
public final class Fetcher {
private static final int DEFAULT_BUFEFR_SIZE = 1024;
private Fetcher() {
}
/**
* Copies the content of a given {@link InputStream} into a fresh byte[],
* using {@code byte[]} as a buffer of default buffer size of one kibibyte (1024 bytes).
*
*
* See
* {@link Fetcher#fetch(InputStream, OutputStream, int, boolean, boolean)}
* for the handling of missing or invalid arguments.
*
* @param in
* The {@link InputStream} to read from.
* @return A new {@code byte[]}, containing the content of the given
* {@link InputStream}.
* @throws IOException
* If anything went wrong while reading from the given
* {@link InputStream}.
*/
public static byte[] fetch(InputStream in) throws IOException {
return fetch(in, DEFAULT_BUFEFR_SIZE, false);
}
/**
* Copies the content of a given {@link InputStream} into a fresh byte[],
* using {@code byte[]} as a buffer.
*
*
* See
* {@link Fetcher#fetch(InputStream, OutputStream, int, boolean, boolean)}
* for the handling of missing or invalid arguments.
*
* @param in
* The {@link InputStream} to read from.
* @param bufferSize
* The size of the buffer.
* @return A new {@code byte[]}, containing the content of the given
* {@link InputStream}.
* @throws IOException
* If anything went wrong while reading from the given
* {@link InputStream}.
*/
public static byte[] fetch(InputStream in, int bufferSize) throws IOException {
return fetch(in, bufferSize, false);
}
/**
* Copies the content of a given {@link InputStream} into a fresh byte[],
* using {@code byte[]} as a buffer of default buffer size of one kibibyte (1024 bytes).
*
*
* See
* {@link Fetcher#fetch(InputStream, OutputStream, int, boolean, boolean)}
* for the handling of missing or invalid arguments.
*
* @param in
* The {@link InputStream} to read from.
* @param close
* Whether to close the given {@link InputStream}, after reading
* from it.
* @return A new {@code byte[]}, containing the content of the given
* {@link InputStream}.
* @throws IOException
* If anything went wrong while reading from the given
* {@link InputStream}. {@link IOException IOExceptions} thrown
* while trying to close the given {@link InputStream}, if
* requested, are ignored.
*/
public static byte[] fetch(InputStream in, boolean close) throws IOException {
return fetch(in, DEFAULT_BUFEFR_SIZE, close);
}
/**
* Copies the content of a given {@link InputStream} into a fresh byte[],
* using a {@code byte[]} as a buffer.
*
*
* See
* {@link Fetcher#fetch(InputStream, OutputStream, int, boolean, boolean)}
* for the handling of missing or invalid arguments.
*
* @param in
* The {@link InputStream} to read from.
* @param bufferSize
* The size of the buffer.
* @param close
* Whether to close the given {@link InputStream}, after reading
* from it.
* @return A new {@code byte[]}, containing the content of the given
* {@link InputStream}.
* @throws IOException
* If anything went wrong while reading from the given
* {@link InputStream}. {@link IOException IOExceptions} thrown
* while trying to close the given {@link InputStream}, if
* requested, are ignored.
*/
public static byte[] fetch(InputStream in, int bufferSize, boolean close) throws IOException {
if (bufferSize < 1) {
bufferSize = DEFAULT_BUFEFR_SIZE;
}
ByteArrayOutputStream out = new ByteArrayOutputStream(bufferSize);
fetch(in, out, bufferSize, close, true);
return out.toByteArray();
}
/**
* Copies the content of a given {@link InputStream} into a given
* {@link OutputStream}, using {@code byte[]} as a buffer of default buffer
* size of one kibibyte
* (1024 bytes).
*
*
* See
* {@link Fetcher#fetch(InputStream, OutputStream, int, boolean, boolean)}
* for the handling of missing or invalid arguments.
*
* @param in
* The {@link InputStream} to read from.
* @param out
* The {@link OutputStream} to write to.
* @throws IOException
* If anything went wrong while reading from the given
* {@link InputStream} or writing to the given
* {@link OutputStream}.
*/
public static void fetch(InputStream in, OutputStream out) throws IOException {
fetch(in, out, DEFAULT_BUFEFR_SIZE, false, false);
}
/**
* Copies the content of a given {@link InputStream} into a given
* {@link OutputStream}, using {@code byte[]} as a buffer of default buffer
* size of one kibibyte
* (1024 bytes).
*
*
* See
* {@link Fetcher#fetch(InputStream, OutputStream, int, boolean, boolean)}
* for the handling of missing or invalid arguments.
*
* @param in
* The {@link InputStream} to read from.
* @param out
* The {@link OutputStream} to write to.
* @param closeIn
* Whether to close the given {@link InputStream}, after reading
* from it.
* @param closeOut
* Whether to close the given {@link OutputStream}, after writing
* to it.
* @throws IOException
* If anything went wrong while reading from the given
* {@link InputStream} or writing to the given
* {@link OutputStream}. {@link IOException IOExceptions} thrown
* while trying to close one of the given streams, if requested,
* are ignored.
*/
public static void fetch(InputStream in, OutputStream out, boolean closeIn, boolean closeOut) throws IOException {
fetch(in, out, DEFAULT_BUFEFR_SIZE, closeIn, closeOut);
}
/**
* Copies the content of a given {@link InputStream} into a given
* {@link OutputStream}, using a {@code byte[]} as a buffer.
*
*
* See
* {@link Fetcher#fetch(InputStream, OutputStream, int, boolean, boolean)}
* for the handling of missing or invalid arguments.
*
* @param in
* The {@link InputStream} to read from.
* @param out
* The {@link OutputStream} to write to.
* @param bufferSize
* The size of the buffer.
* @throws IOException
* If anything went wrong while reading from the given
* {@link InputStream} or writing to the given
* {@link OutputStream}.
*/
public static void fetch(InputStream in, OutputStream out, int bufferSize) throws IOException {
fetch(in, out, bufferSize, false, false);
}
/**
* Copies the content of a given {@link InputStream} into a given
* {@link OutputStream}, using a {@code byte[]} as a buffer.
*
*
* Missing or invalid arguments are handled gracefully with the following
* behaviour.
*
*
* A {@code null} is given as an {@link InputStream}, it is simply ignored
* and handled as if there was nothing to read. If {@code closeOut} is
* {@literal true}, the given {@link OutputStream} will be closed anyway
*
*
* A {@code null} is given as an {@link OutputStream}, it is simply ignored,
* but the content of given {@link InputStream} is fetched anyway. If
* {@code closeIn} is {@literal true}, the given {@link InputStream} will be
* closed anyway
*
*
* A non-positive buffer size is replaced with the default buffer size of
* one kibibyte (1024
* bytes).
*
* @param in
* The {@link InputStream} to read from.
* @param out
* The {@link OutputStream} to write to.
* @param bufferSize
* The size of the buffer.
* @param closeIn
* Whether to close the given {@link InputStream}, after reading
* from it.
* @param closeOut
* Whether to close the given {@link OutputStream}, after writing
* to it.
* @throws IOException
* If anything went wrong while reading from the given
* {@link InputStream} or writing to the given
* {@link OutputStream}. {@link IOException IOExceptions} thrown
* while trying to close one of the given streams, if requested,
* are ignored.
*/
public static void fetch(InputStream in, OutputStream out, int bufferSize, boolean closeIn, boolean closeOut)
throws IOException {
if (bufferSize < 1) {
bufferSize = DEFAULT_BUFEFR_SIZE;
}
try {
if (null != in) {
if (null == out) {
out = new NullOutputStream();
closeOut = true;
}
byte[] buffer = new byte[bufferSize];
int length = in.read(buffer);
while (length != -1) {
out.write(buffer, 0, length);
length = in.read(buffer);
}
}
} catch (IOException e) {
throw e;
} finally {
if (closeIn && null != in) {
try {
in.close();
} catch (IOException e) {
}
}
if (closeOut && null != out) {
try {
out.close();
} catch (IOException e) {
}
}
}
}
}