The java.util.LinkedList.pop() method is used to remove and return the top element from the stack represented by the LinkedList. The method simply pops out an element present at the top of the stack. This method is similar to removeFirst method in LinkedList. Syntax:
LinkedListObject.pop()
Parameters: The method does not take any parameter. Return Value: The method returns the first(top in terms of a stack) value of the stack represented by the LinkedList. Exception: If there is no element in the stack represented by the LinkedList, the pop method will throw NoSuchElementException(). Below program illustrates the of java.util.LinkedList.pop() method: Program 1:
// Java code to demonstrate pop method in LinkedList import java.util.LinkedList;
public class GfG {
// Main method
public static void main(String[] args)
{
// Creating a LinkedList object to represent a stack.
LinkedList<String> stack = new LinkedList<>();
// Pushing an element in the stack
stack.push("Geeks");
// Pushing an element in the stack
stack.push(" for ");
// Pop an element from stack
String s = stack.pop();
// Printing the popped element.
System.out.println(s);
// Pushing an element in the stack
stack.push("Geeks");
// Printing the complete stack.
System.out.println(stack);
}
} |
for [Geeks, Geeks]
Program 2 :
// Java code to demonstrate pop method in LinkedList import java.util.LinkedList;
public class GfG {
// Main method
public static void main(String[] args)
{
// Creating a LinkedList object to represent a stack.
LinkedList<Integer> stack = new LinkedList<>();
// Pushing an element in the stack
stack.push( 10 );
// Pushing an element in the stack
stack.push( 20 );
// Pop an element from stack
Integer ele = stack.pop();
// Printing the popped element.
System.out.println(ele);
// Pop an element from stack
ele = stack.pop();
// Printing the popped element.
System.out.println(ele);
// Throws NoSuchElementException
ele = stack.pop();
// Throws a runtime exception
System.out.println(ele);
// Printing the complete stack.
System.out.println(stack);
}
} |
Output:
20 10 then it will throw : Exception in thread "main" java.util.NoSuchElementException at java.util.LinkedList.removeFirst(LinkedList.java:270) at java.util.LinkedList.pop(LinkedList.java:801) at GfG.main(GfG.java:35)