Question

I currently use

@DefaultAnnotation(NonNull.class)
package jobs;

import edu.umd.cs.findbugs.annotations.DefaultAnnotation;
import edu.umd.cs.findbugs.annotations.NonNull;

however the annotation @edu.umd.cs.findbugs.annotations.DefaultAnnotation is deprecated:
http://findbugs.sourceforge.net/api/edu/umd/cs/findbugs/annotations/DefaultAnnotation.html

They propose to use javax.annotation.ParametersAreNonnullByDefault
However, DefaultAnnotation not only targets parameters, but also fields and methods.

So, what is the javax.annotation alternative for setting fields and methods to Nonnull by default?

Answer 1

As far as I know there is none. Wanting the same thing, I copied the source for ParametersAreNonnullByDefault into my own FieldsAreNonnullByDefault and MethodsAreNonnullByDefault and changed the @TypeQualifierDefault values to match (FIELD and METHOD respective). FindBugs picks up these new annotations perfectly.

Here’s a sample for FieldsAreNonnullByDefault:

package com.sample;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

import javax.annotation.meta.TypeQualifierDefault;

/**
 * This annotation can be applied to a package or class to indicate that the 
 * classes' fields in that element are nonnull by default unless there is
 * <ul>
 *   <li>an explicit nullness annotation
 *   <li>a default field annotation applied to a more tightly nested element.
 * </ul>
 */
@Documented
@Nonnull
@TypeQualifierDefault(ElementType.FIELD)  // <-- METHOD for return values
@Retention(RetentionPolicy.RUNTIME)
public @interface FieldsAreNonnullByDefault {
}