Clover coverage report - Ant Coverage
Coverage timestamp: Tue Apr 8 2003 20:43:55 EST
file stats: LOC: 187   Methods: 7
NCLOC: 54   Classes: 1
 
 Source file Conditionals Statements Methods TOTAL
HeadFilter.java 33.3% 65.2% 85.7% 59.5%
 1   
 /*
 2   
  * The Apache Software License, Version 1.1
 3   
  *
 4   
  * Copyright (c) 2002 The Apache Software Foundation.  All rights
 5   
  * reserved.
 6   
  *
 7   
  * Redistribution and use in source and binary forms, with or without
 8   
  * modification, are permitted provided that the following conditions
 9   
  * are met:
 10   
  *
 11   
  * 1. Redistributions of source code must retain the above copyright
 12   
  *    notice, this list of conditions and the following disclaimer.
 13   
  *
 14   
  * 2. Redistributions in binary form must reproduce the above copyright
 15   
  *    notice, this list of conditions and the following disclaimer in
 16   
  *    the documentation and/or other materials provided with the
 17   
  *    distribution.
 18   
  *
 19   
  * 3. The end-user documentation included with the redistribution, if
 20   
  *    any, must include the following acknowlegement:
 21   
  *       "This product includes software developed by the
 22   
  *        Apache Software Foundation (http://www.apache.org/)."
 23   
  *    Alternately, this acknowlegement may appear in the software itself,
 24   
  *    if and wherever such third-party acknowlegements normally appear.
 25   
  *
 26   
  * 4. The names "Ant" and "Apache Software
 27   
  *    Foundation" must not be used to endorse or promote products derived
 28   
  *    from this software without prior written permission. For written
 29   
  *    permission, please contact apache@apache.org.
 30   
  *
 31   
  * 5. Products derived from this software may not be called "Apache"
 32   
  *    nor may "Apache" appear in their names without prior written
 33   
  *    permission of the Apache Group.
 34   
  *
 35   
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 36   
  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 37   
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 38   
  * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 39   
  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 40   
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 41   
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 42   
  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 43   
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 44   
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 45   
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 46   
  * SUCH DAMAGE.
 47   
  * ====================================================================
 48   
  *
 49   
  * This software consists of voluntary contributions made by many
 50   
  * individuals on behalf of the Apache Software Foundation.  For more
 51   
  * information on the Apache Software Foundation, please see
 52   
  * <http://www.apache.org/>.
 53   
  */
 54   
 package org.apache.tools.ant.filters;
 55   
 
 56   
 import java.io.IOException;
 57   
 import java.io.Reader;
 58   
 import org.apache.tools.ant.types.Parameter;
 59   
 
 60   
 /**
 61   
  * Reads the first <code>n</code> lines of a stream.
 62   
  * (Default is first 10 lines.)
 63   
  * <p>
 64   
  * Example:
 65   
  * <pre>&lt;headfilter lines=&quot;3&quot;/&gt;</pre>
 66   
  * Or:
 67   
  * <pre>&lt;filterreader classname=&quot;org.apache.tools.ant.filters.HeadFilter&quot;&gt;
 68   
  *    &lt;param name=&quot;lines&quot; value=&quot;3&quot;/&gt;
 69   
  * &lt;/filterreader&gt;</pre>
 70   
  *
 71   
  * @author Magesh Umasankar
 72   
  */
 73   
 public final class HeadFilter
 74   
     extends BaseParamFilterReader
 75   
     implements ChainableReader {
 76   
     /** Parameter name for the number of lines to be returned. */
 77   
     private static final String LINES_KEY = "lines";
 78   
 
 79   
     /** Number of lines currently read in. */
 80   
     private long linesRead = 0;
 81   
 
 82   
     /** Number of lines to be returned in the filtered stream. */
 83   
     private long lines = 10;
 84   
 
 85   
     /**
 86   
      * Constructor for "dummy" instances.
 87   
      * 
 88   
      * @see BaseFilterReader#BaseFilterReader()
 89   
      */
 90  1
     public HeadFilter() {
 91  1
         super();
 92   
     }
 93   
 
 94   
     /**
 95   
      * Creates a new filtered reader.
 96   
      *
 97   
      * @param in A Reader object providing the underlying stream.
 98   
      *           Must not be <code>null</code>.
 99   
      */
 100  1
     public HeadFilter(final Reader in) {
 101  1
         super(in);
 102   
     }
 103   
 
 104   
     /**
 105   
      * Returns the next character in the filtered stream. If the desired
 106   
      * number of lines have already been read, the resulting stream is
 107   
      * effectively at an end. Otherwise, the next character from the 
 108   
      * underlying stream is read and returned.
 109   
      * 
 110   
      * @return the next character in the resulting stream, or -1
 111   
      * if the end of the resulting stream has been reached
 112   
      * 
 113   
      * @exception IOException if the underlying stream throws an IOException
 114   
      * during reading     
 115   
      */
 116  49
     public final int read() throws IOException {
 117  49
         if (!getInitialized()) {
 118  0
             initialize();
 119  0
             setInitialized(true);
 120   
         }
 121   
 
 122  49
         int ch = -1;
 123   
 
 124  49
         if (linesRead < lines) {
 125   
 
 126  49
             ch = in.read();
 127   
 
 128  49
             if (ch == '\n') {
 129  4
                 linesRead++;
 130   
             }
 131   
         }
 132   
 
 133  49
         return ch;
 134   
     }
 135   
 
 136   
     /**
 137   
      * Sets the number of lines to be returned in the filtered stream.
 138   
      * 
 139   
      * @param lines the number of lines to be returned in the filtered stream
 140   
      */
 141  2
     public final void setLines(final long lines) {
 142  2
         this.lines = lines;
 143   
     }
 144   
 
 145   
     /**
 146   
      * Returns the number of lines to be returned in the filtered stream.
 147   
      * 
 148   
      * @return the number of lines to be returned in the filtered stream
 149   
      */
 150  1
     private final long getLines() {
 151  1
         return lines;
 152   
     }
 153   
 
 154   
     /**
 155   
      * Creates a new HeadFilter using the passed in
 156   
      * Reader for instantiation.
 157   
      * 
 158   
      * @param rdr A Reader object providing the underlying stream.
 159   
      *            Must not be <code>null</code>.
 160   
      * 
 161   
      * @return a new filter based on this configuration, but filtering
 162   
      *         the specified reader
 163   
      */
 164  1
     public final Reader chain(final Reader rdr) {
 165  1
         HeadFilter newFilter = new HeadFilter(rdr);
 166  1
         newFilter.setLines(getLines());
 167  1
         newFilter.setInitialized(true);
 168  1
         return newFilter;
 169   
     }
 170   
 
 171   
     /**
 172   
      * Scans the parameters list for the "lines" parameter and uses
 173   
      * it to set the number of lines to be returned in the filtered stream.
 174   
      */
 175  0
     private final void initialize() {
 176  0
         Parameter[] params = getParameters();
 177  0
         if (params != null) {
 178  0
             for (int i = 0; i < params.length; i++) {
 179  0
                 if (LINES_KEY.equals(params[i].getName())) {
 180  0
                     lines = new Long(params[i].getValue()).longValue();
 181  0
                     break;
 182   
                 }
 183   
             }
 184   
         }
 185   
     }
 186   
 }
 187