Coverage Report - org.apache.commons.io.input.BoundedInputStream
 
Classes in this File Line Coverage Branch Coverage Complexity
BoundedInputStream
52%
23/44
55%
11/20
2
 
 1  
 /*
 2  
  * Licensed to the Apache Software Foundation (ASF) under one or more
 3  
  * contributor license agreements.  See the NOTICE file distributed with
 4  
  * this work for additional information regarding copyright ownership.
 5  
  * The ASF licenses this file to You under the Apache License, Version 2.0
 6  
  * (the "License"); you may not use this file except in compliance with
 7  
  * the License.  You may obtain a copy of the License at
 8  
  *
 9  
  *      http://www.apache.org/licenses/LICENSE-2.0
 10  
  *
 11  
  * Unless required by applicable law or agreed to in writing, software
 12  
  * distributed under the License is distributed on an "AS IS" BASIS,
 13  
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 14  
  * See the License for the specific language governing permissions and
 15  
  * limitations under the License.
 16  
  */
 17  
 package org.apache.commons.io.input;
 18  
 
 19  
 import java.io.IOException;
 20  
 import java.io.InputStream;
 21  
 
 22  
 /**
 23  
  * This is a stream that will only supply bytes up to a certain length - if its
 24  
  * position goes above that, it will stop.
 25  
  * <p>
 26  
  * This is useful to wrap ServletInputStreams. The ServletInputStream will block
 27  
  * if you try to read content from it that isn't there, because it doesn't know
 28  
  * whether the content hasn't arrived yet or whether the content has finished.
 29  
  * So, one of these, initialized with the Content-length sent in the
 30  
  * ServletInputStream's header, will stop it blocking, providing it's been sent
 31  
  * with a correct content length.
 32  
  *
 33  
  * @version $Id: BoundedInputStream.java 1415850 2012-11-30 20:51:39Z ggregory $
 34  
  * @since 2.0
 35  
  */
 36  
 public class BoundedInputStream extends InputStream {
 37  
 
 38  
     /** the wrapped input stream */
 39  
     private final InputStream in;
 40  
 
 41  
     /** the max length to provide */
 42  
     private final long max;
 43  
 
 44  
     /** the number of bytes already returned */
 45  16
     private long pos = 0;
 46  
 
 47  
     /** the marked position */
 48  16
     private long mark = -1;
 49  
 
 50  
     /** flag if close shoud be propagated */
 51  16
     private boolean propagateClose = true;
 52  
 
 53  
     /**
 54  
      * Creates a new <code>BoundedInputStream</code> that wraps the given input
 55  
      * stream and limits it to a certain size.
 56  
      *
 57  
      * @param in The wrapped input stream
 58  
      * @param size The maximum number of bytes to return
 59  
      */
 60  16
     public BoundedInputStream(final InputStream in, final long size) {
 61  
         // Some badly designed methods - eg the servlet API - overload length
 62  
         // such that "-1" means stream finished
 63  16
         this.max = size;
 64  16
         this.in = in;
 65  16
     }
 66  
 
 67  
     /**
 68  
      * Creates a new <code>BoundedInputStream</code> that wraps the given input
 69  
      * stream and is unlimited.
 70  
      *
 71  
      * @param in The wrapped input stream
 72  
      */
 73  
     public BoundedInputStream(final InputStream in) {
 74  2
         this(in, -1);
 75  2
     }
 76  
 
 77  
     /**
 78  
      * Invokes the delegate's <code>read()</code> method if
 79  
      * the current position is less than the limit.
 80  
      * @return the byte read or -1 if the end of stream or
 81  
      * the limit has been reached.
 82  
      * @throws IOException if an I/O error occurs
 83  
      */
 84  
     @Override
 85  
     public int read() throws IOException {
 86  60
         if (max >= 0 && pos >= max) {
 87  4
             return -1;
 88  
         }
 89  56
         final int result = in.read();
 90  56
         pos++;
 91  56
         return result;
 92  
     }
 93  
 
 94  
     /**
 95  
      * Invokes the delegate's <code>read(byte[])</code> method.
 96  
      * @param b the buffer to read the bytes into
 97  
      * @return the number of bytes read or -1 if the end of stream or
 98  
      * the limit has been reached.
 99  
      * @throws IOException if an I/O error occurs
 100  
      */
 101  
     @Override
 102  
     public int read(final byte[] b) throws IOException {
 103  18
         return this.read(b, 0, b.length);
 104  
     }
 105  
 
 106  
     /**
 107  
      * Invokes the delegate's <code>read(byte[], int, int)</code> method.
 108  
      * @param b the buffer to read the bytes into
 109  
      * @param off The start offset
 110  
      * @param len The number of bytes to read
 111  
      * @return the number of bytes read or -1 if the end of stream or
 112  
      * the limit has been reached.
 113  
      * @throws IOException if an I/O error occurs
 114  
      */
 115  
     @Override
 116  
     public int read(final byte[] b, final int off, final int len) throws IOException {
 117  18
         if (max>=0 && pos>=max) {
 118  6
             return -1;
 119  
         }
 120  12
         final long maxRead = max>=0 ? Math.min(len, max-pos) : len;
 121  12
         final int bytesRead = in.read(b, off, (int)maxRead);
 122  
 
 123  12
         if (bytesRead==-1) {
 124  4
             return -1;
 125  
         }
 126  
 
 127  8
         pos+=bytesRead;
 128  8
         return bytesRead;
 129  
     }
 130  
 
 131  
     /**
 132  
      * Invokes the delegate's <code>skip(long)</code> method.
 133  
      * @param n the number of bytes to skip
 134  
      * @return the actual number of bytes skipped
 135  
      * @throws IOException if an I/O error occurs
 136  
      */
 137  
     @Override
 138  
     public long skip(final long n) throws IOException {
 139  0
         final long toSkip = max>=0 ? Math.min(n, max-pos) : n;
 140  0
         final long skippedBytes = in.skip(toSkip);
 141  0
         pos+=skippedBytes;
 142  0
         return skippedBytes;
 143  
     }
 144  
 
 145  
     /**
 146  
      * {@inheritDoc}
 147  
      */
 148  
     @Override
 149  
     public int available() throws IOException {
 150  0
         if (max>=0 && pos>=max) {
 151  0
             return 0;
 152  
         }
 153  0
         return in.available();
 154  
     }
 155  
 
 156  
     /**
 157  
      * Invokes the delegate's <code>toString()</code> method.
 158  
      * @return the delegate's <code>toString()</code>
 159  
      */
 160  
     @Override
 161  
     public String toString() {
 162  0
         return in.toString();
 163  
     }
 164  
 
 165  
     /**
 166  
      * Invokes the delegate's <code>close()</code> method
 167  
      * if {@link #isPropagateClose()} is {@code true}.
 168  
      * @throws IOException if an I/O error occurs
 169  
      */
 170  
     @Override
 171  
     public void close() throws IOException {
 172  0
         if (propagateClose) {
 173  0
             in.close();
 174  
         }
 175  0
     }
 176  
 
 177  
     /**
 178  
      * Invokes the delegate's <code>reset()</code> method.
 179  
      * @throws IOException if an I/O error occurs
 180  
      */
 181  
     @Override
 182  
     public synchronized void reset() throws IOException {
 183  0
         in.reset();
 184  0
         pos = mark;
 185  0
     }
 186  
 
 187  
     /**
 188  
      * Invokes the delegate's <code>mark(int)</code> method.
 189  
      * @param readlimit read ahead limit
 190  
      */
 191  
     @Override
 192  
     public synchronized void mark(final int readlimit) {
 193  0
         in.mark(readlimit);
 194  0
         mark = pos;
 195  0
     }
 196  
 
 197  
     /**
 198  
      * Invokes the delegate's <code>markSupported()</code> method.
 199  
      * @return true if mark is supported, otherwise false
 200  
      */
 201  
     @Override
 202  
     public boolean markSupported() {
 203  0
         return in.markSupported();
 204  
     }
 205  
 
 206  
     /**
 207  
      * Indicates whether the {@link #close()} method
 208  
      * should propagate to the underling {@link InputStream}.
 209  
      *
 210  
      * @return {@code true} if calling {@link #close()}
 211  
      * propagates to the <code>close()</code> method of the
 212  
      * underlying stream or {@code false} if it does not.
 213  
      */
 214  
     public boolean isPropagateClose() {
 215  0
         return propagateClose;
 216  
     }
 217  
 
 218  
     /**
 219  
      * Set whether the {@link #close()} method
 220  
      * should propagate to the underling {@link InputStream}.
 221  
      *
 222  
      * @param propagateClose {@code true} if calling
 223  
      * {@link #close()} propagates to the <code>close()</code>
 224  
      * method of the underlying stream or
 225  
      * {@code false} if it does not.
 226  
      */
 227  
     public void setPropagateClose(final boolean propagateClose) {
 228  0
         this.propagateClose = propagateClose;
 229  0
     }
 230  
 }