001/*
002 * Copyright 2017 The Error Prone Authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package com.google.errorprone.annotations;
018
019import static java.lang.annotation.ElementType.CONSTRUCTOR;
020import static java.lang.annotation.ElementType.METHOD;
021import static java.lang.annotation.ElementType.PACKAGE;
022import static java.lang.annotation.ElementType.TYPE;
023import static java.lang.annotation.RetentionPolicy.SOURCE;
024
025import java.lang.annotation.Documented;
026import java.lang.annotation.Retention;
027import java.lang.annotation.Target;
028
029/**
030 * Indicates that the return value of the annotated method must be checked. An error is triggered
031 * when one of these methods is called but the result is not used.
032 *
033 * <p>{@code @CheckReturnValue} may be applied to a class or package to indicate that all methods in
034 * that class or package must have their return values checked. For convenience, we provide an
035 * annotation, {@link CanIgnoreReturnValue}, to exempt specific methods or classes from this
036 * behavior.
037 */
038@Documented
039@Target({METHOD, CONSTRUCTOR, TYPE, PACKAGE})
040@Retention(SOURCE)
041public @interface CheckReturnValue {}