Question

Java program please

Exercise 7.2.8: Using the charAt) method, write and run a Java program that rea tring and prints the string in reverse order. (Tip: Once the string has been entere aved, retrieve and display characters starting from the end of the string).

Answer 1

Java Program for Exercise 7.2.8:

import java.util.Scanner;

public class CharTest {
   public static void main(String[]r){
      
       //Scanner instance to read the input from keyboard
       Scanner scanner = new Scanner(System.in);
      
       //asking the user input
       System.out.print("Entery any string:");
       String inputString = scanner.nextLine();
      
       //using for loop and charAt() method,displaying the string in reverse order
       System.out.print("Reverse of "+inputString+" is:");
       for(int i=inputString.length()-1;i>=0;i--){
           System.out.print(inputString.charAt(i));
       }
   }
}

Java Program and Output Screenshot:

public class Char Test f 3 4public static void main (String[]r)t 6 //Scanner instance to read the input from keyboard Scanner scanner new Scanner(System.in); 8 //asking the user input System.out.print ("Entery any string:"); String inputString -scanner.nextLine(); 9 10 //using for loop and charAt ) method,displaying the string in reverse order System.out.print ("Reverse of "+inputString+" is:"); for(int i-inputString.length)-1;i>-0;i--)i System.out.print (inputString.charAt (i)); 14 15 16 17 18 19 20 a Javadoc ConsoleProgresPalettalHierarchy Debug <terminated> CharTest [Java Application] C:AProgram FilesJava\idk1.8.0 161 bin javaw.exe (May 24, 2019, 2:42:11 PM Entery any string:john babu Reverse of john babu is : ubab nhoi

Java Program:

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ButtonDemo extends JFrame
{
/**
   *
   */
   private static final long serialVersionUID = 6216899821916327889L;
  
   /*Buttons declarations*/
   JButton firstButton;
   JButton secondButton;
   JButton thirdButton;
JLabel lbl;
  
/*Constructor to initialize buttons and labels*/
ButtonDemo()
{
firstButton = new JButton("Click on See");
secondButton = new JButton ("Click on Hear");
thirdButton = new JButton ("Click on Speak");
lbl = new JLabel ("");
setLayout (new GridLayout(4,1));
setSize (300,250);
add(firstButton);
add(secondButton);
add(thirdButton);
add(lbl);
setVisible(true);
  
ButtonHandler bh = new ButtonHandler();
firstButton.addActionListener(bh);
secondButton.addActionListener(bh);
thirdButton.addActionListener(bh);
}
  
//class to handle button actions
class ButtonHandler implements ActionListener
{
   //method to perform different actions base on the different buttons
public void actionPerformed(ActionEvent ae)
{
if (ae.getSource()==firstButton)
{
lbl.setText("See no evil");
}
if (ae.getSource()==secondButton)
{
lbl.setText("Hear no evil");
}
if (ae.getSource()==thirdButton)
{
   lbl.setText("Speak no evil");
}
}
}

//main() method - starting point of the program
public static void main(String[] args)
{
   //calling ButtonDemo() constructor
new ButtonDemo();
}
}

Output:

Click on See Click on Hear Click on Speak Hear no evil