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Java Program to display a simple message “A simple Applet” on the applet window – Q46

January 23, 2009 Leave a comment

Q46: Java Program to display a simple message “A simple Applet” on the applet window.

import java.applet.*;
import java.awt.*;

public class Ap_Simple extends Applet{
	public void paint(Graphics g){
		g.drawString("Manoj Pandey", 50, 50);
	}
}

… from College notes (BCA/MCA assignments):

Categories: Java Tags:

Java Program to use all the methods defined by StringBuffer class which are different from String class – Q45

January 23, 2009 Leave a comment

Q45: Java Program to use all the methods defined by StringBuffer class which are different from string class.

class Str_Buffer{
	
	public static void main(String args[]){
		StringBuffer sb = new StringBuffer("Hello");

		System.out.println("buffer before= " + sb);
		System.out.println("charAt(1) before= " + sb.charAt(1));
		
		sb.setCharAt(1, 'i');
		sb.setLength(2);
		
		System.out.println("buffer after= " + sb);
		System.out.println("charAt(1) after= " + sb.charAt(1));
	}
}

… from College notes (BCA/MCA assignments):

Categories: Java Tags:

Java Program to use all the methods defined by string class (substring, indexOf, length, charAt, getchars etc) – Q44

January 22, 2009 Leave a comment

Q44: Java Program to use all the methods defined by string class (substring, indexOf, length, charAt, getchars etc).

class StringMethods{
	public static void main(String args[]){
	    String s = "This is a demo of the getchars method.";
		int start = 10;
		int end = 14;
		char buf[] = new char[end - start];
		s.getChars(start, end, buf, 0);
	
		System.out.println(buf);
		String org = "This is a test. This is, too.";
		String search = "is";
		String sub = "was";
		String result = "";
		int i;
		
		do{
			System.out.println(" ");
			System.out.println(org);
			i = org.indexOf(search);
			if(i != -1){
				result = org.substring(0, i);
				result = result + sub;
				result = result + org.substring(i + search.length());
				org = result;
			}
		}while(i != -1);
	}
}

… from College notes (BCA/MCA assignments):

Categories: Java Tags:

Java Program to handle object serialization using ObjectInputStream and ObjectOutputStream – Q43

January 22, 2009 Leave a comment

Q43: Java Program to handle object serialization using ObjectInputStream and ObjectOutputStream.

import java.io.*;

public class SerializationDemo{
	public static void main(String args[]){
		try{
			Myclass object1 = new Myclass("Hello", -7, 2.7e10);
			System.out.println("object1: " + object1);
			FileOutputStream fos = new FileOutputStream("serial");
			ObjectOutputStream oos = new ObjectOutputStream(fos);
			oos.writeObject(object1);
			oos.flush();
			oos.close();
		}
		catch(IOException e){
			System.out.println("Exception during serialization: " + e);
			System.exit(0);
			
		}
		try{
			Myclass object2;
			FileInputStream fis = new FileInputStream("serial");
			ObjectInputStream ois = new ObjectInputStream(fis);
			object2 = (Myclass)ois.readObject();
			ois.close();
			System.out.println("object2: " + object2);
		}
		catch(Exception e){
			System.out.println("Exception during Deserialization: " + e);
			System.exit(0);
		}
	}
}
class Myclass implements Serializable{
	String s;
	int i;
	double d;
	public Myclass(String s, int i, double d){
		this.s = s;
		this.i = i;
		this.d = d;
	}
	public String toString(){
		return "s= " + s + "; i= " + i + "; d= " + d;
	}
}

… from College notes (BCA/MCA assignments):

Categories: Java Tags: ,

Java Program to print integers you have input through console using BufferedReader and StringTokenizer – Q42

January 21, 2009 Leave a comment

Q42: Java Program to print integers you have input through console using BufferedReader and StringTokenizer.

import java.util.*;
import java.io.*;

class Buf_R_Str_Token{
	public static void main(String args[]) throws IOException{
		BufferedReader b_r = new BufferedReader(new 
InputStreamReader(System.in));
		String str = b_r.readLine();
		
		StringTokenizer st = new StringTokenizer(str, ",");
		
		String item;
		try{
			while((item = st.nextToken()) != null){
				System.out.print(" " + item);
			}
		}
		catch(Exception e){
			System.out.println("\n End of String.");
		}
	}
}

… from College notes (BCA/MCA assignments):

Categories: Java Tags: ,