New to Java

Hi every body
I am new 2 java
I am struck in editing a text file that ends with .dat
I successfully added,viewed data of the *.dat file.
but,I cannt edit,delete the lines that i need to do randomly.

Here is the code i have written.

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.LineNumberReader;
import java.io.RandomAccessFile;
import java.util.ArrayList;
import java.util.StringTokenizer;

public class ReadWriteFile {
	String id=null;
	String name=null;
	String dept=null;
	String doj=null;
	String adrss=null;
	
	public void WriteFile(String Id,String Name,String Dept,String Doj,String Adrss) throws IOException{
		
		File f=new File("TraineeDetails.dat");
	    if(!f.exists()){
	    f.createNewFile();
	    }
		BufferedWriter bw=new BufferedWriter(new FileWriter("TraineeDetails.dat",true));
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		System.out.print("Enter Id : ");
		Id=br.readLine();
		System.out.print("Enter name : ");
		Name=br.readLine();
		System.out.print("Enter dept : ");
		Dept=br.readLine();
		System.out.print("Enter doj : ");
		Doj=br.readLine();
		System.out.print("Enter adrss : ");
		Adrss=br.readLine();
		bw.write(Id+"::"+Name+"::"+Dept+"::"+Doj+"::"+Adrss+":END:");
		bw.flush();
		bw.newLine();
		bw.close();
		
		
	}
	
	public static void main(String[] args) throws IOException {
		ReadWriteFile rwf=new ReadWriteFile();
		String TID = null;
		String TADRSS = null;
		String TDOJ = null;
		String TNAME = null;
		String TDEPT = null;
		rwf.ReadFile(TID,TNAME,TDEPT,TDOJ,TADRSS);

	}
	public void ReadFile(String Id1,String Name1,String Dept1,String Doj1,String Adrss1) throws IOException{
		
		BufferedReader br = new BufferedReader(new FileReader("TraineeDetails.dat"));
		String s;
				
	      while((s = br.readLine())!= null) 
	      {

	        // Create string tokenizer
	    	  StringTokenizer st =new StringTokenizer(s, "::");
		      
		        System.out.println("----------------------------------------------");
		        System.out.println("| Trainee Id: "+st.nextToken()             +"|");
		        System.out.println("| Trainee Name: "+st.nextToken()           +"|");
		        System.out.println("| Trainee Department:"+st.nextToken()      +"|");
		        System.out.println("| Date of Joining: "+st.nextToken()        +"|");
		        System.out.println("| Trainee Address: "+st.nextToken()        +"|\n");
		        System.out.println("----------------------------------------------");
       
	      }
	      // Close file reader
	      br.close();
	}
}

and here is the data i have written

Trainee.dat*
111::jain::roads::2-2008::Blore:END:
123::tim::service::1-2000::delhi:END:
444::faru::civil::3-2200::sanapur:END:
555::niv::cse::10-2000::gnagar:END:
999::linda::mech::6-2001::tnagar:END:
258::yansi::geo::8-2002::rtnagar:END:
656::hari::garrage::3-1000::uttarahalli:END:
888::muni::hr::5-2009::ernakulam:END:
007::bond::spy::2-1972::america:END:
0123::landy::games::6-2003::hdp:END:
678::maddy::pumbing::4-1999::dispur:END: