| /* |
| * 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.io; |
| |
| import static org.apache.commons.io.IOUtils.EOF; |
| |
| import java.io.ByteArrayInputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.InputStreamReader; |
| import java.io.OutputStream; |
| import java.io.OutputStreamWriter; |
| import java.io.Reader; |
| import java.io.StringReader; |
| import java.io.Writer; |
| import java.nio.charset.Charset; |
| |
| /** |
| * This class provides static utility methods for buffered |
| * copying between sources ({@link InputStream}, {@link Reader}, |
| * {@link String} and {@code byte[]}) and destinations |
| * ({@link OutputStream}, {@link Writer}, {@link String} and |
| * {@code byte[]}). |
| * <p> |
| * Unless otherwise noted, these {@code copy} methods do <em>not</em> |
| * flush or close the streams. Often doing so would require making non-portable |
| * assumptions about the streams' origin and further use. This means that both |
| * streams' {@code close()} methods must be called after copying. if one |
| * omits this step, then the stream resources (sockets, file descriptors) are |
| * released when the associated Stream is garbage-collected. It is not a good |
| * idea to rely on this mechanism. For a good overview of the distinction |
| * between "memory management" and "resource management", see |
| * <a href="http://www.unixreview.com/articles/1998/9804/9804ja/ja.htm">this |
| * UnixReview article</a>. |
| * <p> |
| * For byte-to-char methods, a {@code copy} variant allows the encoding |
| * to be selected (otherwise the platform default is used). We would like to |
| * encourage you to always specify the encoding because relying on the platform |
| * default can lead to unexpected results. |
| * <p> |
| * We don't provide special variants for the {@code copy} methods that |
| * let you specify the buffer size because in modern VMs the impact on speed |
| * seems to be minimal. We're using a default buffer size of 4 KB. |
| * <p> |
| * The {@code copy} methods use an internal buffer when copying. It is |
| * therefore advisable <em>not</em> to deliberately wrap the stream arguments |
| * to the {@code copy} methods in {@code Buffered*} streams. For |
| * example, don't do the following: |
| * <pre> |
| * copy( new BufferedInputStream( in ), new BufferedOutputStream( out ) ); |
| * </pre> |
| * The rationale is as follows: |
| * <p> |
| * Imagine that an InputStream's read() is a very expensive operation, which |
| * would usually suggest wrapping in a BufferedInputStream. The |
| * BufferedInputStream works by issuing infrequent |
| * {@link java.io.InputStream#read(byte[] b, int off, int len)} requests on the |
| * underlying InputStream, to fill an internal buffer, from which further |
| * {@code read} requests can inexpensively get their data (until the buffer |
| * runs out). |
| * <p> |
| * However, the {@code copy} methods do the same thing, keeping an |
| * internal buffer, populated by |
| * {@link InputStream#read(byte[] b, int off, int len)} requests. Having two |
| * buffers (or three if the destination stream is also buffered) is pointless, |
| * and the unnecessary buffer management hurts performance slightly (about 3%, |
| * according to some simple experiments). |
| * <p> |
| * Behold, intrepid explorers; a map of this class: |
| * <pre> |
| * Method Input Output Dependency |
| * ------ ----- ------ ------- |
| * 1 copy InputStream OutputStream (primitive) |
| * 2 copy Reader Writer (primitive) |
| * |
| * 3 copy InputStream Writer 2 |
| * |
| * 4 copy Reader OutputStream 2 |
| * |
| * 5 copy String OutputStream 2 |
| * 6 copy String Writer (trivial) |
| * |
| * 7 copy byte[] Writer 3 |
| * 8 copy byte[] OutputStream (trivial) |
| * </pre> |
| * <p> |
| * Note that only the first two methods shuffle bytes; the rest use these |
| * two, or (if possible) copy using native Java copy methods. As there are |
| * method variants to specify the encoding, each row may |
| * correspond to up to 2 methods. |
| * <p> |
| * Provenance: Excalibur. |
| * |
| * @deprecated Use IOUtils. Will be removed in 3.0. |
| * Methods renamed to IOUtils.write() or IOUtils.copy(). |
| * Null handling behavior changed in IOUtils (null data does not |
| * throw NullPointerException). |
| */ |
| @Deprecated |
| public class CopyUtils { |
| |
| /** |
| * Copies bytes from a {@code byte[]} to an {@link OutputStream}. |
| * @param input the byte array to read from |
| * @param output the {@link OutputStream} to write to |
| * @throws IOException In case of an I/O problem |
| */ |
| public static void copy(final byte[] input, final OutputStream output) throws IOException { |
| output.write(input); |
| } |
| |
| /** |
| * Copies and convert bytes from a {@code byte[]} to chars on a |
| * {@link Writer}. |
| * The platform's default encoding is used for the byte-to-char conversion. |
| * |
| * @param input the byte array to read from |
| * @param output the {@link Writer} to write to |
| * @throws IOException In case of an I/O problem |
| * @deprecated 2.5 use {@link #copy(byte[], Writer, String)} instead |
| */ |
| @Deprecated |
| public static void copy(final byte[] input, final Writer output) throws IOException { |
| final ByteArrayInputStream inputStream = new ByteArrayInputStream(input); |
| copy(inputStream, output); |
| } |
| |
| /** |
| * Copies and convert bytes from a {@code byte[]} to chars on a |
| * {@link Writer}, using the specified encoding. |
| * |
| * @param input the byte array to read from |
| * @param output the {@link Writer} to write to |
| * @param encoding The name of a supported character encoding. See the |
| * <a href="http://www.iana.org/assignments/character-sets">IANA |
| * Charset Registry</a> for a list of valid encoding types. |
| * @throws IOException In case of an I/O problem |
| */ |
| public static void copy(final byte[] input, final Writer output, final String encoding) throws IOException { |
| final ByteArrayInputStream inputStream = new ByteArrayInputStream(input); |
| copy(inputStream, output, encoding); |
| } |
| |
| /** |
| * Copies bytes from an {@link InputStream} to an |
| * {@link OutputStream}. |
| * |
| * @param input the {@link InputStream} to read from |
| * @param output the {@link OutputStream} to write to |
| * @return the number of bytes copied |
| * @throws IOException In case of an I/O problem |
| */ |
| public static int copy(final InputStream input, final OutputStream output) throws IOException { |
| final byte[] buffer = IOUtils.byteArray(); |
| int count = 0; |
| int n; |
| while (EOF != (n = input.read(buffer))) { |
| output.write(buffer, 0, n); |
| count += n; |
| } |
| return count; |
| } |
| |
| /** |
| * Copies and convert bytes from an {@link InputStream} to chars on a |
| * {@link Writer}. |
| * The platform's default encoding is used for the byte-to-char conversion. |
| * |
| * @param input the {@link InputStream} to read from |
| * @param output the {@link Writer} to write to |
| * @throws IOException In case of an I/O problem |
| * @deprecated 2.5 use {@link #copy(InputStream, Writer, String)} instead |
| */ |
| @Deprecated |
| public static void copy( |
| final InputStream input, |
| final Writer output) |
| throws IOException { |
| // make explicit the dependency on the default encoding |
| final InputStreamReader in = new InputStreamReader(input, Charset.defaultCharset()); |
| copy(in, output); |
| } |
| |
| /** |
| * Copies and convert bytes from an {@link InputStream} to chars on a |
| * {@link Writer}, using the specified encoding. |
| * |
| * @param input the {@link InputStream} to read from |
| * @param output the {@link Writer} to write to |
| * @param encoding The name of a supported character encoding. See the |
| * <a href="http://www.iana.org/assignments/character-sets">IANA |
| * Charset Registry</a> for a list of valid encoding types. |
| * @throws IOException In case of an I/O problem |
| */ |
| public static void copy( |
| final InputStream input, |
| final Writer output, |
| final String encoding) |
| throws IOException { |
| final InputStreamReader in = new InputStreamReader(input, encoding); |
| copy(in, output); |
| } |
| |
| /** |
| * Serialize chars from a {@link Reader} to bytes on an |
| * {@link OutputStream}, and flush the {@link OutputStream}. |
| * Uses the default platform encoding. |
| * |
| * @param input the {@link Reader} to read from |
| * @param output the {@link OutputStream} to write to |
| * @throws IOException In case of an I/O problem |
| * @deprecated 2.5 use {@link #copy(Reader, OutputStream, String)} instead |
| */ |
| @Deprecated |
| public static void copy( |
| final Reader input, |
| final OutputStream output) |
| throws IOException { |
| // make explicit the dependency on the default encoding |
| final OutputStreamWriter out = new OutputStreamWriter(output, Charset.defaultCharset()); |
| copy(input, out); |
| // XXX Unless anyone is planning on rewriting OutputStreamWriter, we |
| // have to flush here. |
| out.flush(); |
| } |
| |
| /** |
| * Serialize chars from a {@link Reader} to bytes on an |
| * {@link OutputStream}, and flush the {@link OutputStream}. |
| * |
| * @param input the {@link Reader} to read from |
| * @param output the {@link OutputStream} to write to |
| * @param encoding The name of a supported character encoding. See the |
| * <a href="http://www.iana.org/assignments/character-sets">IANA |
| * Charset Registry</a> for a list of valid encoding types. |
| * @throws IOException In case of an I/O problem |
| * @since 2.5 |
| */ |
| public static void copy( |
| final Reader input, |
| final OutputStream output, |
| final String encoding) |
| throws IOException { |
| final OutputStreamWriter out = new OutputStreamWriter(output, encoding); |
| copy(input, out); |
| // XXX Unless anyone is planning on rewriting OutputStreamWriter, we |
| // have to flush here. |
| out.flush(); |
| } |
| |
| /** |
| * Copies chars from a {@link Reader} to a {@link Writer}. |
| * |
| * @param input the {@link Reader} to read from |
| * @param output the {@link Writer} to write to |
| * @return the number of characters copied |
| * @throws IOException In case of an I/O problem |
| */ |
| public static int copy( |
| final Reader input, |
| final Writer output) |
| throws IOException { |
| final char[] buffer = IOUtils.getScratchCharArray(); |
| int count = 0; |
| int n; |
| while (EOF != (n = input.read(buffer))) { |
| output.write(buffer, 0, n); |
| count += n; |
| } |
| return count; |
| } |
| |
| /** |
| * Serialize chars from a {@link String} to bytes on an |
| * {@link OutputStream}, and |
| * flush the {@link OutputStream}. |
| * Uses the platform default encoding. |
| * |
| * @param input the {@link String} to read from |
| * @param output the {@link OutputStream} to write to |
| * @throws IOException In case of an I/O problem |
| * @deprecated 2.5 use {@link #copy(String, OutputStream, String)} instead |
| */ |
| @Deprecated |
| public static void copy( |
| final String input, |
| final OutputStream output) |
| throws IOException { |
| final StringReader in = new StringReader(input); |
| // make explicit the dependency on the default encoding |
| final OutputStreamWriter out = new OutputStreamWriter(output, Charset.defaultCharset()); |
| copy(in, out); |
| // XXX Unless anyone is planning on rewriting OutputStreamWriter, we |
| // have to flush here. |
| out.flush(); |
| } |
| |
| /** |
| * Serialize chars from a {@link String} to bytes on an |
| * {@link OutputStream}, and |
| * flush the {@link OutputStream}. |
| * |
| * @param input the {@link String} to read from |
| * @param output the {@link OutputStream} to write to |
| * @param encoding The name of a supported character encoding. See the |
| * <a href="http://www.iana.org/assignments/character-sets">IANA |
| * Charset Registry</a> for a list of valid encoding types. |
| * @throws IOException In case of an I/O problem |
| * @since 2.5 |
| */ |
| public static void copy( |
| final String input, |
| final OutputStream output, |
| final String encoding) |
| throws IOException { |
| final StringReader in = new StringReader(input); |
| final OutputStreamWriter out = new OutputStreamWriter(output, encoding); |
| copy(in, out); |
| // XXX Unless anyone is planning on rewriting OutputStreamWriter, we |
| // have to flush here. |
| out.flush(); |
| } |
| |
| /** |
| * Copies chars from a {@link String} to a {@link Writer}. |
| * |
| * @param input the {@link String} to read from |
| * @param output the {@link Writer} to write to |
| * @throws IOException In case of an I/O problem |
| */ |
| public static void copy(final String input, final Writer output) |
| throws IOException { |
| output.write(input); |
| } |
| |
| /** |
| * Instances should NOT be constructed in standard programming. |
| * |
| * @deprecated TODO Make private in 4.0. |
| */ |
| @Deprecated |
| public CopyUtils() { |
| // empty |
| } |
| |
| } |