NumberedLineReader


1   package SnowMailClient.utils;
2   
3   import java.util.*;
4   import java.io.*;
5   
6   
7   /** the number is usually used a human-readable debug information
8       this also stores a cache of the last line.
9   */
10  public class NumberedLineReader extends BufferedReader
11  {
12    private int lineNumber = 0;
13    private String   lastLine = null;
14    /** only for one line !
15    */
16    private boolean undo = false;
17  
18  
19    public NumberedLineReader(String   cont)
20    {
21       super( new StringReader( cont ) );
22    } // Constructor
23  
24  
25    public final String   readLine() throws IOException
26    {
27       if(undo)
28       {
29         undo = false;
30       }
31       else
32       {
33         lineNumber++;
34         lastLine = super.readLine();
35       }
36       return lastLine;
37    }
38  
39    /** this undoes the read of the last line.
40     => the next readLine will return exactely the same line
41    */
42    public final void undoRead()
43    {
44      if(undo==true)         throw new RuntimeException  ("Only one undo allowed !");
45      if(lastLine==null) throw new RuntimeException  ("No line to undo !");
46      this.undo = true;
47    }
48  
49    public final String   getLastLineCached() { return lastLine; }
50  
51    public final int getLineNumber() { return lineNumber; }
52  
53  } // NumberedLineReader

A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame

Popular Tags