Casting boolean to Boolean in java – Education Career Blog

i have a code as

public class BooleanTest {
    public BooleanTest() {

    public static void main(String args){
      BooleanTest bt = new BooleanTest();


    private boolean method() {
        return false;

    private void doProcess() {
      Boolean obj = (Boolean)method();

the question is can line System.out.println(obj.booleanValue()); throw NullPointerException in any situation?


No, when you box a primitive value into its equivalent wrapper type, the result is never null.



Reason: primitive never hold null so converting them to Wrapper will never lead to NPE,

And also no need to caste it will autobox


It will never throw a NPE and also if you are using java >= 1.5, you don’t need to cast it. It is called autoboxing which is introduced from JDK 1.5.


Just to be pedantic, you might have set System.out to be null, then that line will generate an NPE.

But that would be odd.

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