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1   /**
2    * Redistribution  and use  in source  and binary  forms, with  or without
3    * modification, are permitted provided  that the following conditions are
4    * met :
5    *
6    * . Redistributions  of  source  code  must  retain  the  above copyright
7    *   notice, this list of conditions and the following disclaimer.
8    *
9    * . Redistributions in  binary form  must reproduce  the above  copyright
10   *   notice, this list of conditions  and the following disclaimer in  the
11   *   documentation and/or other materials provided with the distribution.
12   *
13   * . The name of the author may not be used to endorse or promote products
14   *   derived from this software without specific prior written permission.
15   *
16   * THIS SOFTWARE IS  PROVIDED BY THE  AUTHOR ``AS IS''  AND ANY EXPRESS  OR
17   * IMPLIED  WARRANTIES,  INCLUDING,  BUT   NOT  LIMITED  TO,  THE   IMPLIED
18   * WARRANTIES OF MERCHANTABILITY AND  FITNESS FOR A PARTICULAR  PURPOSE ARE
19   * DISCLAIMED.  IN NO  EVENT SHALL  THE AUTHOR  BE LIABLE  FOR ANY  DIRECT,
20   * INDIRECT,  INCIDENTAL,  SPECIAL,  EXEMPLARY,  OR  CONSEQUENTIAL  DAMAGES
21   * (INCLUDING,  BUT  NOT LIMITED  TO,  PROCUREMENT OF  SUBSTITUTE  GOODS OR
22   * SERVICES;  LOSS  OF USE,  DATA,  OR PROFITS;  OR  BUSINESS INTERRUPTION)
23   * HOWEVER CAUSED  AND ON  ANY THEORY  OF LIABILITY,  WHETHER IN  CONTRACT,
24   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25   * ANY  WAY  OUT OF  THE  USE OF  THIS  SOFTWARE, EVEN  IF  ADVISED OF  THE
26   * POSSIBILITY OF SUCH DAMAGE.
27   */
28  
29  package cpptools;
30  
31  import java.io.BufferedReader;
32  import java.io.FileReader;
33  import java.io.IOException;
34  
35  /**
36   * Captures behaviours common to loggers.
37   *
38   * @author Mathieu Champlon
39   */
40  public abstract class AbstractLogger implements EventHandler
41  {
42      private static final double MS_PER_S = 1000.0;
43      private static final int ERROR_LINES_DISPLAYED = 3;
44      private long start;
45  
46      /**
47       * {@inheritDoc}
48       */
49      public final void started()
50      {
51          start = System.currentTimeMillis();
52      }
53  
54      /**
55       * {@inheritDoc}
56       */
57      public final void finished( final int parsed, final int total )
58      {
59          final long end = System.currentTimeMillis();
60          final double time = (end - start) / MS_PER_S;
61          log( "Successfully parsed " + parsed + " / " + total + " files in " + time + " s" );
62      }
63  
64      /**
65       * Log a given message.
66       *
67       * @param message the message
68       */
69      protected abstract void log( String message );
70  
71      /**
72       * {@inheritDoc}
73       */
74      public final void display( final String filename, final int line, final int column )
75      {
76          try
77          {
78              displayLocation( line, ERROR_LINES_DISPLAYED, filename );
79              displayCursor( column );
80          }
81          catch( IOException e )
82          {
83              error( "internal", e, "while trying to display error location" );
84          }
85      }
86  
87      private void displayCursor( final int column )
88      {
89          final StringBuffer line = new StringBuffer();
90          for( int i = 0; i < column - 1; ++i )
91              line.append( ' ' );
92          log( line.append( '^' ).toString() );
93      }
94  
95      private void displayLocation( final int start, final int lines, final String filename ) throws IOException
96      {
97          final BufferedReader reader = new BufferedReader( new FileReader( filename ) );
98          try
99          {
100             for( int i = 0; i < start - lines; i++ )
101                 reader.readLine();
102             for( int i = 0; i < lines; ++i )
103                 log( reader.readLine() );
104         }
105         finally
106         {
107             reader.close();
108         }
109     }
110 }