Stack using Java Stack Utils Example in Java

Introduction

Stack Using Java Stack Utils is a classic Java console program that demonstrates the concept with complete source code and sample output. Classic data structures such as stack, queue and linked list implemented in Java.

This tutorial walks through the program line by line, explains how the logic works, and highlights best practices you can apply in your own code.

Definition

A stack is a basic computer science data structure and can be defined in an abstract, implementation-free manner, or it can be generally defined as a linear list of items in which all additions and deletion are restricted to one end that is Top.

Stack Using Java Stack Utils Example Program

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Stack;

class StackProgram {

    public static void main(String[] args) throws IOException {
        Stack stk = new Stack();
        stk.setSize(5);
        
        boolean yes=true;
        int choice;
        BufferedReader is = new BufferedReader(new InputStreamReader(System.in));
        
        do{
            System.out.println("1).Push\n2).Pop\n3).Exit\n\nEnter Choice");
            choice = Integer.parseInt(is.readLine());
            
            switch(choice)
            {
                case 1: System.out.println("Enter Push Item: ");
                        stk.push(Integer.parseInt(is.readLine()));
                        break;
                case 2: System.out.println("Poped Item : "+stk.pop());break;
                case 3: yes = false;break;
                default: System.out.println("Invalid Choice");
            }
        }while(yes==true);
        
    }
}

Sample Output

1).Push
2).Pop
3).Exit

Enter Choice
1
Enter Push Item: 
23
1).Push
2).Pop
3).Exit

Enter Choice
1
Enter Push Item: 
45
1).Push
2).Pop
3).Exit

Enter Choice
2
Poped Item : 45
1).Push
2).Pop
3).Exit

Enter Choice
2
Poped Item : 23
1).Push
2).Pop
3).Exit

When to use

Use this stack using java stack utils example when learning or revising core Java syntax.

How it works

1. Execution begins in the main method — the JVM calls this method when you run the class.

2. import java.io.BufferedReader; imports a class used later in the program.

3. import java.io.IOException; imports a class used later in the program.

4. import java.io.InputStreamReader; imports a class used later in the program.

5. import java.util.Stack; imports a class used later in the program.

6. Stack stk = new Stack(); updates a variable used in the calculation or output.

7. boolean yes=true; updates a variable used in the calculation or output.

8. A println / print call writes text to the console — part of the sample output below.

Best Practices

• Use meaningful variable and class names that describe their purpose.
• Compile and run the program locally — modify values to see how output changes.
• Read compiler errors carefully; they usually point to the exact line to fix.

Common Mistakes

• Copying code without understanding each line — practice by changing one statement at a time.
• Mismatching the public class name and the .java filename.
• Forgetting semicolons at the end of statements.