This check prevents calls to methods annotated with Error Prone’s @DoNotCall
annotation (com.google.errorprone.annotations.DoNotCall
).
The check disallows invocations and method references of the annotated method.
There are a few situations where this can be useful, including methods that are required to satisfy the contract of an interface, but that are not supported.
A method annotated with @DoNotCall
should always be final
or abstract
. If
an abstract
method is annotated @DoNotCall
Error Prone will ensure all
implementations of that method also have the annotation. Methods annotated with
@DoNotCall
should not be private, since a private method that should not be
called can simply be removed.
TIP: Marking methods annotated with @DoNotCall
as @Deprecated
is
recommended, since it provides IDE users with more immediate feedback.
Example:
java.util.Collection#add
should never be called on an immutable collection
implementation:
package com.google.common.collect.ImmutableList;
class ImmutableList<E> implements List<E> {
// ...
/**
* Guaranteed to throw an exception and leave the list unmodified.
*
* @deprecated Unsupported operation.
*/
@Deprecated
@DoNotCall("guaranteed to throw an exception and leave the list unmodified")
@Override
public final void add(E e) {
throw new UnsupportedOperationException();
}
}
Suppress false positives by adding the suppression annotation @SuppressWarnings("DoNotCall")
to the enclosing element.