javamavenannotationsnullpointerexceptionfindbugs

How do I get @ParametersAreNonnullByDefault to work?

I've made several attempts at getting package annotation @ParametersAreNonnullByDefault to work for me in a maven project but with no success. Could someone share a link to a minimal/sample maven project where this is setup (or post the pom.xml and package-info.java and demo class)?

I'm talking about having findbugs processor enforce it for me.

Solution

  • How to apply @ParametersAreNonnullByDefault

    Create a file package-info.java in your package where you want to enforce the desired behavior.

    In that file, do the following:

    /**
 * You should do it like this!
 */
@ParametersAreNonnullByDefault
package com.stackoverflow;

import javax.annotation.ParametersAreNonnullByDefault;

    How not to apply @ParametersAreNonnullByDefault

    Don't do the following in a Java source file:

    /**
 * But you shouldn't do it this way!
 */
@ParametersAreNonnullByDefault
package com.stackoverflow;

import javax.annotation.ParametersAreNonnullByDefault;

public class Answer { ...

    Declaring annotations like this is ambiguous.

    Notes

    It would be OK to apply the annotation directly on Answer class.

    package com.stackoverflow;

import javax.annotation.ParametersAreNonnullByDefault;

/**
 * You can do it like this also.
 */
@ParametersAreNonnullByDefault
public class Answer { ...

    The exact same things apply to @ParametersAreNullableByDefault also.