Save This Page
Home » openjdk-7 » sun » misc » [javadoc | source]
    1   /*
    2    * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved.
    3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
    4    *
    5    * This code is free software; you can redistribute it and/or modify it
    6    * under the terms of the GNU General Public License version 2 only, as
    7    * published by the Free Software Foundation.  Oracle designates this
    8    * particular file as subject to the "Classpath" exception as provided
    9    * by Oracle in the LICENSE file that accompanied this code.
   10    *
   11    * This code is distributed in the hope that it will be useful, but WITHOUT
   12    * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   13    * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   14    * version 2 for more details (a copy is included in the LICENSE file that
   15    * accompanied this code).
   16    *
   17    * You should have received a copy of the GNU General Public License version
   18    * 2 along with this work; if not, write to the Free Software Foundation,
   19    * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   20    *
   21    * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   22    * or visit www.oracle.com if you need additional information or have any
   23    * questions.
   24    */
   25   
   26   /**
   27    * IOUtils: A collection of IO-related public static methods.
   28    */
   29   
   30   package sun.misc;
   31   
   32   import java.io.EOFException;
   33   import java.io.IOException;
   34   import java.io.InputStream;
   35   import java.util.Arrays;
   36   
   37   public class IOUtils {
   38   
   39       /**
   40        * Read up to <code>length</code> of bytes from <code>in</code>
   41        * until EOF is detected.
   42        * @param in input stream, must not be null
   43        * @param length number of bytes to read, -1 or Integer.MAX_VALUE means
   44        *        read as much as possible
   45        * @param readAll if true, an EOFException will be thrown if not enough
   46        *        bytes are read. Ignored when length is -1 or Integer.MAX_VALUE
   47        * @return bytes read
   48        * @throws IOException Any IO error or a premature EOF is detected
   49        */
   50       public static byte[] readFully(InputStream is, int length, boolean readAll)
   51               throws IOException {
   52           byte[] output = {};
   53           if (length == -1) length = Integer.MAX_VALUE;
   54           int pos = 0;
   55           while (pos < length) {
   56               int bytesToRead;
   57               if (pos >= output.length) { // Only expand when there's no room
   58                   bytesToRead = Math.min(length - pos, output.length + 1024);
   59                   if (output.length < pos + bytesToRead) {
   60                       output = Arrays.copyOf(output, pos + bytesToRead);
   61                   }
   62               } else {
   63                   bytesToRead = output.length - pos;
   64               }
   65               int cc = is.read(output, pos, bytesToRead);
   66               if (cc < 0) {
   67                   if (readAll && length != Integer.MAX_VALUE) {
   68                       throw new EOFException("Detect premature EOF");
   69                   } else {
   70                       if (output.length != pos) {
   71                           output = Arrays.copyOf(output, pos);
   72                       }
   73                       break;
   74                   }
   75               }
   76               pos += cc;
   77           }
   78           return output;
   79       }
   80   }

Save This Page
Home » openjdk-7 » sun » misc » [javadoc | source]