Question

You are to write a class StringPlay that has only a main method. This class contains all interaction with the user.

The main method

• Uses a Scanner to accept user input
• Maintains a “current” String
• Uses a sentinel-controlled loop to accept multiple user commands, or exit
• The program displays a message asking the user to enter one of the following commands
  • a – enter a new value for current
  • b – padLeft asks the user for the number of characters to add to the start of the current string, and the character to use for the padding
  • c – padRight asks the user for the number of characters to add to the end of the current string, and the character to use for the padding
  • d – zapLeft asks the user for the number of characters to remove from the start of the current string
  • e – zapRight asks the user for the number of characters to remove from the end of the current string
  • f – exits the program
• The loop body performs its actions using the appropriate method from StringUtils.
• After the action is completed, the loop displays the current string and prompts for another command.

Notes

Use Scanner’s next method for the “e” command; we will limit our user input to have no spaces or other whitespace. Similarly, padding characters will not be whitespace. You may assume valid user input.

Answer 1

Sample Output:

The screenshots are attached below for reference.

Please follow them for proper output.

Program code to copy:

import java.util.*;
public class StringPlay{
public static void main (String[] args) {
Scanner inp=new Scanner(System.in);
String current="";
System.out.println("Enter the current string:");
current=inp.next();//read current string
char ch='a';
int n=0;
while(ch!='f'){
System.out.println("The current string is:"+current);//print current string
System.out.println("a-Enter a new value for current:");
System.out.println("b-padLeft");//print menu options
System.out.println("c-padRight");
System.out.println("d-zapLeft");
System.out.println("e-zapRight");
System.out.println("f-exit");
System.out.println("Enter choice:");
ch=inp.next().charAt(0);//read choice from user
if(ch=='a'){
System.out.println("Enter the value for current string:");
current=inp.next();
}
else if(ch=='b'){
System.out.println("Enter number of characters to add:");
n=inp.nextInt();
System.out.println("Enter character:");//read input from user
ch=inp.next().charAt(0);
String res="";
for(int i=0;i<n;i++){
res=res+ch;//create a new string and add characters at front
}
res+=current;
current=res;///update current with res string
}
else if(ch=='c'){
System.out.println("Enter number of characters to add:");
n=inp.nextInt();
System.out.println("Enter character:");
ch=inp.next().charAt(0);//read input from user
for(int i=0;i<n;i++){
current=current+ch;//add characters
}
}
else if(ch=='d'){
System.out.println("Enter number of characters to remove:");
n=inp.nextInt();//read input from user
n=n-1;
String res="";
for(int i=n;i<current.length();i++){
res=res+current.charAt(i);//add charaters to res String from current string after n positions
}
current=res;
}
else if(ch=='e'){
System.out.println("Enter number of characters to remove:");
n=inp.nextInt();
String res="";
for(int i=0;i<current.length()-n;i++){
res=res+current.charAt(i);//add characters to res from current string till n characters from last
}
current=res;
}
else{
break;
}
  
}
}
}