crcgen.java

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


public class crcgen extends JApplet  implements ActionListener
 {
  JButton b1,b2,b3;
  JPanel p0,p1,p2,p3,p4,p5;
  JLabel l1,l2,l3,l4,l5,l6;
  JLabel st=new JLabel();
  JLabel df=new JLabel();
  JFrame f=new JFrame();
  String crcfile=new String();
  public crcgen()
   {
		f.setVisible(true);
		f.setBounds(250,250,540,400);
		f.setTitle("CRC Generation");
		f.setResizable(false);
		Image img=Toolkit.getDefaultToolkit().getImage("ddsm113.jpg");
				 f.setIconImage(img);
		
		p0=new JPanel();
		p1=new JPanel();
		p2=new JPanel();
		p3=new JPanel();
		p4=new JPanel();
		p5=new JPanel();

		l3=new JLabel();
		p0.setBackground(Color.darkGray);
		p1.setBackground(Color.gray);
		 p2.setBackground(Color.gray);
		  p3.setBackground(Color.gray);
		   p4.setBackground(Color.gray);
			p5.setBackground(Color.gray);
		p0.setLayout(new FlowLayout(FlowLayout.LEFT,0,0));
		l1=new JLabel("CRC GENERATION",JLabel.LEFT);
		l1.setFont(new Font("TimesRoman",Font.BOLD,30));
		l1.setForeground(Color.lightGray);
		l4=new JLabel("Choose File",JLabel.LEFT);
		l4.setFont(new Font("TimesRoman",Font.BOLD,20));
		l4.setForeground(Color.black);
		p2.setLayout(new FlowLayout(FlowLayout.CENTER,10,20));
		p3.setLayout(new FlowLayout(FlowLayout.CENTER,50,0));
		p4.setLayout(new FlowLayout(FlowLayout.LEFT,20,40));
		p5.setLayout(new FlowLayout(FlowLayout.LEFT,20,0));
		l2=new JLabel("Selected File :-",JLabel.LEFT);
		l2.setFont(new Font("TimesRoman",Font.BOLD,15));
		l2.setForeground(Color.black);
		l5=new JLabel("Generated File :-",JLabel.LEFT);
		l5.setFont(new Font("TimesRoman",Font.BOLD,15));
		l5.setForeground(Color.black);

		l6=new JLabel();

		st.setFont(new Font("TimesRoman",Font.BOLD,15));
		st.setForeground(Color.black);

		df.setFont(new Font("TimesRoman",Font.BOLD,15));
		df.setForeground(Color.black);


		b1=new JButton("Browse...");
		b2=new JButton(" GENERATE ");
		b3=new JButton("   CANCEL   ");
		b1.addActionListener(this);
		b2.addActionListener(this);
		b3.addActionListener(this);

		p0.add(l1);
		p2.add(l4);
		p2.add(b1);
		p3.add(b2);
		p3.add(b3);
		p4.add(l2);
		p4.add(st);
		p5.add(l5);
		p5.add(df);
		p1.setLayout(new GridLayout(4,1,0,0));
		f.getContentPane().add(p0,BorderLayout.NORTH);
		f.getContentPane().add(p1,BorderLayout.CENTER);
		p1.add(p2);
		p1.add(p3);
		p1.add(p4);
		p1.add(p5);
		
		}
  
  public void actionPerformed(ActionEvent ae)
   {
     JFrame jp;
     jp=new JFrame();
     FileDialog fd=new FileDialog(jp,"fd",FileDialog.LOAD);
     fd.setFile("*.*;");

     String m=new String();
     if(ae.getSource()==b1)
     {
     fd.setVisible(true);
     fd.getFile();
     l3.setText(fd.getFile());
     st.setText(fd.getDirectory()+fd.getFile());
     l6.setText(fd.getDirectory());
     }
     if(ae.getSource()==b2)
      {
       try
       {
        m=l3.getText();
        generate(m);
       }
       catch(Exception e)
        { }
       }
     
	 else if(ae.getSource()==b3)
     { 
		 f.setVisible(false);
		 f.dispose();
     }

   }
  
  public void generate(String fp) throws Exception
  {
    
	File file=new File(fp);
    crcfile=fp.substring(0,fp.lastIndexOf(".")+1) + "crc";
    String filename=file.getName();
    StringBuffer sb=new StringBuffer(filename);
    sb.setLength(20);
    BufferedInputStream fin=new BufferedInputStream(new FileInputStream(fp));
    DataOutputStream fout=new DataOutputStream(new FileOutputStream(crcfile));
    fout.write(sb.toString().getBytes());
    CRC32 crc=new CRC32();
    df.setText(l6.getText()+crcfile);    
    int b;
    while((b=fin.read())!=-1) {
      fout.write(b);
      crc.update(b);
    }

    long checksum=crc.getValue();
    fout.writeLong(checksum);
    
    fin.close();
     fout.close();
  }
}