src/main/java/de/todesbaum/util/io/TeeOutputStream.java

   1 /*
   2  * jSite - TeeOutputStream.java - Copyright © 2010–2019 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package de.todesbaum.util.io;
  19
  20 import java.io.IOException;
  21 import java.io.OutputStream;
  22
  23 /**
  24  * {@link OutputStream} that sends all data it receives to multiple other output
  25  * streams. If an error occurs during a {@link #write(int)} to one of the
  26  * underlying output streams no guarantees are made about how much data is sent
  27  * to each stream, i.e. there is no good way to recover from such an error.
  28  *
  29  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  30  */
  31 public class TeeOutputStream extends OutputStream {
  32
  33         /** The output streams. */
  34         private final OutputStream[] outputStreams;
  35
  36         /**
  37          * Creates a new tee output stream that sends all to all given output
  38          * streams.
  39          *
  40          * @param outputStreams
  41          *            The output streams to send all data to
  42          */
  43         public TeeOutputStream(OutputStream... outputStreams) {
  44                 this.outputStreams = outputStreams;
  45         }
  46
  47         /**
  48          * {@inheritDoc}
  49          * <p>
  50          * An effort is made to close all output streams. If multiple exceptions
  51          * occur, only the first exception is thrown after all output streams have
  52          * been tried to close.
  53          */
  54         @Override
  55         public void close() throws IOException {
  56                 IOException occuredException = null;
  57                 for (OutputStream outputStream : outputStreams) {
  58                         try {
  59                                 outputStream.flush();
  60                         } catch (IOException ioe1) {
  61                                 if (occuredException == null) {
  62                                         occuredException = ioe1;
  63                                 }
  64                         }
  65                 }
  66                 if (occuredException != null) {
  67                         throw occuredException;
  68                 }
  69         }
  70
  71         /**
  72          * {@inheritDoc}
  73          * <p>
  74          * An effort is made to flush all output streams. If multiple exceptions
  75          * occur, only the first exception is thrown after all output streams have
  76          * been tried to flush.
  77          */
  78         @Override
  79         public void flush() throws IOException {
  80                 IOException occuredException = null;
  81                 for (OutputStream outputStream : outputStreams) {
  82                         try {
  83                                 outputStream.flush();
  84                         } catch (IOException ioe1) {
  85                                 if (occuredException == null) {
  86                                         occuredException = ioe1;
  87                                 }
  88                         }
  89                 }
  90                 if (occuredException != null) {
  91                         throw occuredException;
  92                 }
  93         }
  94
  95         /**
  96          * {@inheritDoc}
  97          */
  98         @Override
  99         public void write(byte[] buffer) throws IOException {
 100                 for (OutputStream outputStream : outputStreams) {
 101                         outputStream.write(buffer);
 102                 }
 103         }
 104
 105         /**
 106          * {@inheritDoc}
 107          */
 108         @Override
 109         public void write(byte[] buffer, int offset, int length) throws IOException {
 110                 for (OutputStream outputStream : outputStreams) {
 111                         outputStream.write(buffer, offset, length);
 112                 }
 113         }
 114
 115         /**
 116          * {@inheritDoc}
 117          */
 118         @Override
 119         public void write(int data) throws IOException {
 120                 for (OutputStream outputStream : outputStreams) {
 121                         outputStream.write(data);
 122                 }
 123         }
 124
 125 }