Java stack implementation

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Examples

package com.w3schools;
 
public class Test {
    private int stackSize;
    private int[] stackArr;
    private int top;
 
    /**
     * constructor to create stack with size
     * @param size
     */
    public Test(int size) {
        this.stackSize = size;
        this.stackArr = new int[stackSize];
        this.top = -1;
    }
 
    /**
     * Adds new entry to the top of the stack
     * @param entry
     * @throws Exception 
     */
    public void push(int entry) throws Exception {
        if(this.isStackFull()){
        	System.out.println("Stack Overflow");
        }
        System.out.println("Adding: "+entry);
        this.stackArr[++top] = entry;
    }
 
    /**
     * Removes an entry from the top of the stack.
     * @return
     * @throws Exception 
     */
    public int pop() throws Exception {
        if(this.isStackEmpty()){
        	System.out.println("Stack underflow.");
        }
        int entry = this.stackArr[top--];
        System.out.println("Removed entry: "+entry);
        return entry;
    }
 
    /**
     * Returns top of the stack without removing it.
     * @return
     */
    public int peek() {
        return stackArr[top];
    }
 
    /**
     * Returns true if the stack is empty
     * @return
     */
    public boolean isStackEmpty() {
        return (top == -1);
    }
 
    /**
     * Returns true if the stack is full
     * @return
     */
    public boolean isStackFull() {
        return (top == stackSize - 1);
    }
 
  public static void main(String args[]){
	Test stack = new Test(4);
	try {
		stack.push(14);
		stack.push(82);
		stack.push(32);
		stack.push(8);
		stack.pop();
		stack.push(3);
		stack.pop();
		stack.pop();
		stack.pop();
		stack.pop();
		stack.pop();
		stack.pop();
	} catch (Exception e) {
		System.out.println(e.getMessage());
	}
  }
}

Output

Adding: 14
Adding: 82
Adding: 32
Adding: 8
Removed entry: 8
Adding: 3
Removed entry: 3
Removed entry: 32
Removed entry: 82
Removed entry: 14
Stack underflow.
-1