Java Code to implement a Stack using Java Generics

In this post I have implemented Stack using Java Generics and the LinkedList class. This post isn't a tutorial rather an implementation of Stack Data Structure.

Code for Stack Interface : StackInterface.java

	package com.codehackersblog.JStack;
	/**
	*
	* @author Psycho_Coder
	* @param <T>
	*/
	public interface StackInterface<T> {
	/**
	*
	* @param item This method push the item passed into the stack
	*/
	public abstract void push(T item);
	/**
	*
	* @return This method removes the top element from the stack
	*/
	public abstract T pop();
	/**
	*
	* @return This method returns whether the stack is empty or not
	*/
	public abstract boolean isEmpty();
	/**
	*
	* @return This Methods returns the top element of the stack
	*/
	public abstract T peek();
	/**
	*
	* @return This method returns the size of the stack
	*/
	public abstract int size();
	/**
	*
	* @return This method returns the array of the items in the stack
	*/
	public abstract String display();
	}

view raw StackInterface.java hosted with ❤ by GitHub

Code for Stack Interface : JStack.java

	package com.codehackersblog.JStack;
	import java.util.Iterator;
	import java.util.LinkedList;
	/**
	*
	* @author Psycho_Coder
	* @param <T>
	*/
	public class JStack<T> implements StackInterface<T> {
	private LinkedList<T> list;
	public JStack() {
	this.list = new LinkedList<>();
	}
	/*
	* @see com.psychocoder.JStack.StackInterface#push(java.lang.Object)
	*/
	@Override
	public synchronized void push(T item) {
	list.addFirst(item);
	}
	/*
	* @see com.psychocoder.JStack.StackInterface#pop()
	*/
	@Override
	public synchronized T pop() {
	return list.removeFirst();
	}
	/*
	* @see com.psychocoder.JStack.StackInterface#isEmpty()
	*/
	@Override
	public boolean isEmpty() {
	return list.isEmpty();
	}
	/*
	* @see com.psychocoder.JStack.StackInterface#peek()
	*/
	@Override
	public synchronized T peek() {
	return list.getFirst();
	}
	/*
	* @see com.psychocoder.JStack.StackInterface#size()
	*/
	@Override
	public int size() {
	return list.size();
	}
	/*
	* @see com.psychocoder.JStack.StackInterface#display()
	*/
	@Override
	public String display() {
	String m = "";
	for (Iterator<T> it = list.iterator(); it.hasNext();) {
	m = m + it.next() + " ";
	}
	return m;
	}
	/**
	* @returns An array of all the element in the stack
	*/
	public Object[] elements() {
	return list.toArray();
	}
	}

view raw JStack.java hosted with ❤ by GitHub

Demo Run of Above Implementation

	import com.codehackersblog.JStack.JStack;
	/**
	*
	* @author psychocoder
	*/
	public class JStackDemo {
	public static void main(String[] args) {
	JStack<String> jstack = new JStack();
	jstack.push("1");
	jstack.push("2");
	jstack.push("3");
	jstack.push("4");
	System.out.println("Print All Elements in Stack : \n");
	for (Object m : jstack.elements()) {
	System.out.println(m.toString());
	}
	jstack.pop();
	jstack.pop();
	System.out.println("\nAll Elements in Stack are : \n" + jstack.display());
	System.out.println("\nTop Element : " + jstack.peek());
	jstack.push("3");
	jstack.push("4");
	System.out.println("\nSize of Stack : " + jstack.size());
	}
	}

view raw JStackDemo.java hosted with ❤ by GitHub

Output

Print All Elements in Stack : 

4
3
2
1

All Elements in Stack are : 
2 1 

Top Element : 2

Size of Stack : 4