Java by API/java.util/Stack

new Stack()

 
/*
 * Output:
 * 
stack: []
push(42)
stack: [42]
pop -> 42
stack: []
empty stack

 *  
 */
import java.util.Stack;
import java.util.EmptyStackException;
public class MainClass {
  public static void main(String args[]) {
    Stack st = new Stack();
    System.out.println("stack: " + st);
    st.push(new Integer(42));
    System.out.println("push(" + 42 + ")");
    System.out.println("stack: " + st);
    System.out.print("pop -> ");
    Integer a = (Integer) st.pop();
    System.out.println(a);
    System.out.println("stack: " + st);
    try {
      st.pop();
    } catch (EmptyStackException e) {
      System.out.println("empty stack");
    }
  }
}

new Stack < E > ()

 
/**
 *Output: 
stack: []
push(2)
stack: [2]
push(6)
stack: [2, 6]
push(9)
stack: [2, 6, 9]
pop -> 9
stack: [2, 6]
pop -> 6
stack: [2]
*/
import java.util.EmptyStackException;
import java.util.Stack;
  
public class MainClass {
  static void showpush(Stack<Integer> st, int a) { 
    st.push(a); 
    System.out.println("push(" + a + ")"); 
    System.out.println("stack: " + st); 
  } 
 
  static void showpop(Stack<Integer> st) { 
    System.out.print("pop -> "); 
    Integer a = st.pop(); 
    System.out.println(a); 
    System.out.println("stack: " + st); 
  } 
 
  public static void main(String args[]) { 
    Stack<Integer> st = new Stack<Integer>(); 
 
    System.out.println("stack: " + st); 
    showpush(st, 2); 
    showpush(st, 6); 
    showpush(st, 9); 
    showpop(st); 
 
    try { 
      showpop(st); 
    } catch (EmptyStackException e) { 
      System.out.println("empty stack"); 
    } 
  } 
}

Stack: empty()

 
import java.util.Stack;
public class Main {
  public static void main (String args[]) {
    Stack<String> s = new Stack<String>();
    s.push("A");
    s.push("B");
    s.push("C");
    System.out.println(s.pop());
    System.out.println(s.empty());
  }
}

Stack: peek()

 
import java.util.Stack;
public class Main {
  public static void main (String args[]) {
    Stack<String> s = new Stack<String>();
    s.push("A");
    s.push("B");
    s.push("C");
    System.out.println("Next: " + s.peek());
  }
}

Stack: pop()

 
/*
 * Output:
 * 
stack: []
push(42)
stack: [42]
pop -> 42
stack: []
empty stack

 *  
 */
import java.util.Stack;
import java.util.EmptyStackException;
public class MainClass {
  public static void main(String args[]) {
    Stack st = new Stack();
    System.out.println("stack: " + st);
    st.push(new Integer(42));
    System.out.println("push(" + 42 + ")");
    System.out.println("stack: " + st);
    System.out.print("pop -> ");
    Integer a = (Integer) st.pop();
    System.out.println(a);
    System.out.println("stack: " + st);
    try {
      st.pop();
    } catch (EmptyStackException e) {
      System.out.println("empty stack");
    }
  }
}

Stack: push(E item)

 
/*
 * Output:
 * 
stack: []
push(42)
stack: [42]
pop -> 42
stack: []
empty stack

 *  
 */
import java.util.Stack;
import java.util.EmptyStackException;
public class MainClass {
  public static void main(String args[]) {
    Stack st = new Stack();
    System.out.println("stack: " + st);
    st.push(new Integer(42));
    System.out.println("push(" + 42 + ")");
    System.out.println("stack: " + st);
    System.out.print("pop -> ");
    Integer a = (Integer) st.pop();
    System.out.println(a);
    System.out.println("stack: " + st);
    try {
      st.pop();
    } catch (EmptyStackException e) {
      System.out.println("empty stack");
    }
  }
}

Stack: search(Object o)

 

import java.util.Stack;
public class Main {
  public static void main (String args[]) {
    Stack<String> s = new Stack<String>();
    s.push("A");
    s.push("B");
    s.push("C");
    System.out.println("Next: " + s.peek());
    s.push("D");
    System.out.println(s.pop());
    s.push("E");
    s.push("F");
    int count = s.search("E");
    while (count != -1 && count > 1) {
      s.pop();
      count--;
    }
    System.out.println(s);
  }
}