com.netflix.hystrix.contrib.javanica.aop.aspectj.HystrixCommandAspect.java Source code

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Here is the source code for com.netflix.hystrix.contrib.javanica.aop.aspectj.HystrixCommandAspect.java

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/**
 * Copyright 2012 Netflix, Inc.
 *
 * 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.netflix.hystrix.contrib.javanica.aop.aspectj;

import com.netflix.hystrix.HystrixExecutable;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixCollapser;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import com.netflix.hystrix.contrib.javanica.collapser.CommandCollapser;
import com.netflix.hystrix.contrib.javanica.command.CommandExecutor;
import com.netflix.hystrix.contrib.javanica.command.ExecutionType;
import com.netflix.hystrix.contrib.javanica.command.GenericHystrixCommandFactory;
import com.netflix.hystrix.contrib.javanica.command.MetaHolder;
import com.netflix.hystrix.exception.HystrixBadRequestException;
import org.apache.commons.lang3.Validate;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;

import java.lang.reflect.Method;

import static com.netflix.hystrix.contrib.javanica.utils.AopUtils.getMethodFromTarget;

/**
 * AspectJ aspect to process methods which annotated with {@link HystrixCommand} annotation.
 */
@Aspect
public class HystrixCommandAspect {

    @Pointcut("@annotation(com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand)")
    public void hystrixCommandAnnotationPointcut() {
    }

    @Around("hystrixCommandAnnotationPointcut()")
    public Object methodsAnnotatedWithHystrixCommand(final ProceedingJoinPoint joinPoint) throws Throwable {

        Method method = getMethodFromTarget(joinPoint);
        Object obj = joinPoint.getTarget();
        Object[] args = joinPoint.getArgs();
        Validate.notNull(method, "failed to get method from joinPoint: %s", joinPoint);
        HystrixCommand hystrixCommand = method.getAnnotation(HystrixCommand.class);
        HystrixCollapser hystrixCollapser = method.getAnnotation(HystrixCollapser.class);
        ExecutionType executionType = ExecutionType.getExecutionType(method.getReturnType());
        Method cacheKeyMethod = getMethodFromTarget(joinPoint, hystrixCommand.cacheKeyMethod());
        MetaHolder metaHolder = MetaHolder.builder().args(args).method(method).obj(obj)
                .proxyObj(joinPoint.getThis()).cacheKeyMethod(cacheKeyMethod).executionType(executionType)
                .hystrixCommand(hystrixCommand).hystrixCollapser(hystrixCollapser)
                .defaultCommandKey(method.getName()).defaultCollapserKey(method.getName())
                .defaultGroupKey(obj.getClass().getSimpleName()).build();
        HystrixExecutable executable;
        if (hystrixCollapser != null) {
            executable = new CommandCollapser(metaHolder);
        } else {
            executable = GenericHystrixCommandFactory.getInstance().create(metaHolder, null);
        }
        Object result;
        try {
            result = CommandExecutor.execute(executable, executionType);
        } catch (HystrixBadRequestException e) {
            throw e.getCause();
        } catch (Throwable throwable) {
            throw throwable;
        }
        return result;
    }

}