Stacks Algorithms

Writing a Stack using Array

package com.saroj.stack;
/**
 * @author saroj
 *
 */
public class MyStack {
	public static void main(String[] args) {
		Stack myStack = new Stack(10);
		for(int i=0; i<10; i++){
			myStack.push(i);
		}
		for(int i=0; i<5; i++){
			System.out.println(myStack.pop());
		}
	}
	
	static class Stack{
		int size;
		int top;
		int[] array;
		
		public Stack(int maxSize){
			this.size=maxSize;
			top = -1;
			array = new int[maxSize];
		}
		
		public void push(int val){
			array[++top] = val;
		}
		public int pop(){
			int result = array[top];
			top--;
			return result;
		}
		
		public int peek(){
			return array[top];
		}
	}

}

Writing a Dynamic Stack using resized Array

package com.saroj.stack;

/**
 * @author saroj
 *
 */
public class MyDynamicStack {

	public static void main(String[] args) {
		DynamicStack myStack = new DynamicStack(10);
		for(int i=0; i<10; i++){
			myStack.push(i);
		}
		for(int i=0; i<5; i++){
			System.out.println(myStack.pop());
		}

	}
	
 static class DynamicStack{
	 int size;
	 int[] stackArr;
	 int top;
	 
	 public DynamicStack(int maxSize){
		 top = -1;
		 this.size=maxSize;
		 stackArr = new int[maxSize];
		 
	 }
	 
	 public void push(int val){
		 if(isFull()){
			 increaseCapacity();
		 }else{
			 stackArr[++top] = val;
		 }
	 }
	 
	 public int pop(){
		 if(isEmpty()){
			 throw new RuntimeException("Stack is empty");
		 }
		 int item = this.stackArr[top--];
		 return item;
	 }
	 // To check if the stack is full
	 public boolean isFull(){
		 return (top == stackArr.length-1);
	 }
	 //check if the stack is empty
	 public boolean isEmpty(){
		 return (top == -1);
	 }
	 //increase the capacity fo stack
	 public void increaseCapacity(){
		 int[] newArray = new int[this.size*2];
		 for(int i=0; i<size;i++){
			 newArray[i] = stackArr[i];
		 }
		 this.stackArr = newArray;
		 this.size=size*2;
	 }	 
 }

}

How to sort a Stack without using any data structure like array etc.?

package com.saroj.stack;

import java.util.Stack;

public class SortingAStack {
     public static void main(String[] args) {
	Stack stack = new Stack();
	stack.push(10);
	stack.push(5);
	stack.push(3);
	stack.push(12);
	stack.push(6);
	stack.push(7);
	stack.push(1);
	stack.push(14);
	System.out.println(SortingAStack.sort(stack));
	}
	
    public static Stack sort(Stack stack1){
	Stack stack2 = new Stack();
	   while(!stack1.isEmpty()){
	       int temp = stack1.pop();
		while(!stack2.isEmpty() && stack2.peek() > temp){
		   stack1.push(stack2.pop());
		}
		stack2.push(temp);
	    }
	    return stack2;
	}
}