/*
* Copyright 2014 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.errorprone.refaster.annotation;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Indicates that a parameter to a placeholder method is not required to be used in the
* placeholder's implementation. For example, the pattern
*
* <pre><code>
* abstract class Utf8Bytes {
* {@literal @}Placeholder abstract void handleException(
* {@literal @}MayOptionallyUse UnsupportedEncodingException e);
* {@literal @}Placeholder abstract void useString(String str);
* {@literal @}BeforeTemplate void before(byte[] array) {
* try {
* useString(new String(array, "UTF_8"));
* } catch (UnsupportedEncodingException e) {
* handleException(e);
* }
* }
* {@literal @}AfterTemplate void after(byte[] array) {
* useString(new String(array, StandardCharsets.UTF_8));
* }
* }
* </code></pre>
*
* would match even if the catch statement were empty, or didn't refer to e.
*/
@Target(ElementType.PARAMETER)
@Retention(RetentionPolicy.SOURCE)
public @interface MayOptionallyUse {
}