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Show all versions of spring-retry Show documentation
Spring Retry provides an abstraction around retrying failed operations, with an
emphasis on declarative control of the process and policy-based behaviour that is
easy to extend and customize. For instance, you can configure a plain POJO
operation to retry if it fails, based on the type of exception, and with a fixed
or exponential backoff.
/*
* Copyright 2006-2022 the original author or authors.
*
* 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
*
* https://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 org.springframework.classify.util;
import java.lang.annotation.Annotation;
import java.lang.annotation.ElementType;
import java.lang.annotation.Target;
import java.lang.reflect.Method;
import java.util.concurrent.atomic.AtomicReference;
import org.springframework.aop.support.AopUtils;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;
import org.springframework.util.ReflectionUtils;
/**
* MethodResolver implementation that finds a single Method on the given Class
* that contains the specified annotation type.
*
* @author Mark Fisher
*/
public class AnnotationMethodResolver implements MethodResolver {
private final Class annotationType;
/**
* Create a MethodResolver for the specified Method-level annotation type
* @param annotationType the type of the annotation
*/
public AnnotationMethodResolver(Class annotationType) {
Assert.notNull(annotationType, "annotationType must not be null");
Assert.isTrue(
ObjectUtils.containsElement(annotationType.getAnnotation(Target.class).value(), ElementType.METHOD),
"Annotation [" + annotationType + "] is not a Method-level annotation.");
this.annotationType = annotationType;
}
/**
* Find a single Method on the Class of the given candidate object that
* contains the annotation type for which this resolver is searching.
* @param candidate the instance whose Class will be checked for the annotation
* @return a single matching Method instance or null if the candidate's
* Class contains no Methods with the specified annotation
* @throws IllegalArgumentException if more than one Method has the specified
* annotation
*/
public Method findMethod(Object candidate) {
Assert.notNull(candidate, "candidate object must not be null");
Class targetClass = AopUtils.getTargetClass(candidate);
if (targetClass == null) {
targetClass = candidate.getClass();
}
return this.findMethod(targetClass);
}
/**
* Find a single Method on the given Class that contains the annotation type
* for which this resolver is searching.
* @param clazz the Class instance to check for the annotation
* @return a single matching Method instance or null if the Class
* contains no Methods with the specified annotation
* @throws IllegalArgumentException if more than one Method has the specified
* annotation
*/
public Method findMethod(final Class clazz) {
Assert.notNull(clazz, "class must not be null");
final AtomicReference annotatedMethod = new AtomicReference<>();
ReflectionUtils.doWithMethods(clazz, method -> {
Annotation annotation = AnnotationUtils.findAnnotation(method, annotationType);
if (annotation != null) {
Assert.isNull(annotatedMethod.get(), "found more than one method on target class [" + clazz
+ "] with the annotation type [" + annotationType + "]");
annotatedMethod.set(method);
}
});
return annotatedMethod.get();
}
}