traceviewer.java

JAVA Servlet2.3外文书籍源码

package debugging;

import java.util.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;

/**
  * A class to visualize a debug trace.
  */
public class TraceViewer extends JFrame implements ListCellRenderer
{

  /**
    * The main() method reads the log output from a text file and
    * then displays the logged invocations. The log file name is supplied
    * as a command line argument.
    */
  public static void main(String args[]) 
  {
    if (args.length<1) System.exit(0);

    // -- get inocations from the log file --
    Vector invocations=TraceViewer.getInvocations(args[0]);

    // -- display them --
    TraceViewer.displayInvocations(invocations); 
  }

  /**
    * This method reads a set of tagged lines, from the given file,
    * which corresponding with method invocations.
    */
  private static Vector getInvocations(String fileName)
  {
    Vector invocations=new Vector();

    try
    {
      BufferedReader reader=new BufferedReader(new FileReader(fileName));

      String thisLine=reader.readLine();
      while (thisLine!=null)
      {
        InvocationRecord thisInvocation=null;

        // -- create an invocation record from this line --
        if (thisLine.length()>0)
          thisInvocation=new InvocationRecord(thisLine);

        // -- add it to the Vector --
        if (thisInvocation!=null)
          invocations.addElement(thisInvocation);

        thisLine=reader.readLine();
      }
    
      reader.close();
    }
    catch (Exception ex)
    {
      ex.printStackTrace();
    }

    return invocations;
  }

  /**
    * Static method to create a TraceViewer instance with a set of
    * invocations to be visualised.
    */
  public static void displayInvocations(Vector invocations)
  {
    // -- call the TraceViewer constructor with a set of invocations --
    TraceViewer traceViewer=new TraceViewer(invocations);

    traceViewer.addWindowListener(
      new WindowAdapter()
      {
        public void windowClosing(WindowEvent event) {System.exit(0);}
      }
    );

    // -- display it --
    traceViewer.setSize(500,500);
    traceViewer.setVisible(true);
  }

  /**
    * The constructor creates a JList with a set of invocations
    * as the content to be visualised.
    */
  public TraceViewer(Vector invocations)
  {
    JList traceList=new JList(invocations);
    traceList.setCellRenderer(this);
    getContentPane().add(new JScrollPane(traceList));
  }

  /**
    * This method is called automatically, and repeatedly, to render
    * element of the JList.
    */
  public Component getListCellRendererComponent(JList list, Object value
  , int index, boolean isSelected, boolean cellHasFocus)
  {
    // -- Here's the thing we're going to display --
    InvocationRecord thisInvocation=(InvocationRecord) value;

    // -- Create a Jpanel to hold everything --
    JPanel invocationPanel=new JPanel();
    invocationPanel.setLayout(new GridLayout(6,1));

	Font labelFont=new Font("Courier",Font.PLAIN,11);

    // -- Create a "sender" Label --
    JLabel senderLabel=new JLabel("SENDER: " + thisInvocation.sender);
    senderLabel.setFont(labelFont);
    senderLabel.setForeground(Color.black);

    // -- Create a "message" Label --
    JLabel messageLabel=new JLabel("  MESSAGE: " + thisInvocation.message);
    messageLabel.setFont(labelFont);
    messageLabel.setForeground(Color.black);

    // -- Create a "receiver" Label --
    JLabel receiverLabel=new JLabel("  RECEIVER: " + thisInvocation.receiver);
    receiverLabel.setFont(labelFont);
    receiverLabel.setForeground(Color.black);

    // -- Create a "thread" Label --
    JLabel threadLabel=new JLabel("  THREAD: " + thisInvocation.thread);
    threadLabel.setFont(labelFont);
    threadLabel.setForeground(Color.black);

    // -- Create a "duration" Label --
    JLabel durationLabel=new JLabel("  DURATION: " + thisInvocation.duration);
    durationLabel.setFont(labelFont);
    durationLabel.setForeground(Color.black);

    // -- Add everything to the panel --
    invocationPanel.add(senderLabel);
    invocationPanel.add(messageLabel);
    invocationPanel.add(receiverLabel);
    invocationPanel.add(threadLabel);
    invocationPanel.add(durationLabel);
    invocationPanel.add(new JLabel(""));

    invocationPanel.setBackground(Color.white);
    invocationPanel.setOpaque(true);
    return invocationPanel;
  }

}

/**
  * This class represents an individual invocation record to be
  * displayed.
  */
class InvocationRecord
{
  public String sender="";
  public String message="";
  public String receiver="";
  public String thread="";
  public String duration="";

  /**
    * The constructor makes an invocation record from the
    * tagged input.
    */
  public InvocationRecord(String taggedText)
  {
    sender=InvocationRecord.getField(taggedText,"sender");
    message=InvocationRecord.getField(taggedText,"message");
    receiver=InvocationRecord.getField(taggedText,"receiver");
    thread=InvocationRecord.getField(taggedText,"thread");
    duration=InvocationRecord.getField(taggedText,"duration");
    if (duration.length()>0)
      duration=duration+"ms";
  }

  /**
    * This method extracts the content of a given tag.
    */
  public static String getField(String taggedText, String tag)
  {
    String fieldValue="";

    int startPos=taggedText.indexOf("<"+tag+">");
    int endPos=taggedText.indexOf("</"+tag+">");

    if ( (startPos>=0) && (endPos>startPos) )
    {
      startPos=startPos+tag.length()+2;
      fieldValue=taggedText.substring(startPos,endPos);
    }

    return fieldValue;
  }
}