2、Hystrix参数配置示例
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import com.mimaxueyuan.consumer.turbine.service.MyService;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixProperty;
import com.netflix.hystrix.contrib.javanica.conf.HystrixPropertiesManager;
@RestController
public class HystrixController {
@Autowired
private MyService myService;
/**
* @HystrixCommand由名为“javanica”的Netflix contrib库提供 。
* Spring Cloud在连接到Hystrix断路器的代理中使用该注解自动包装Spring bean。
* 断路器计算何时打开和关闭电路，以及在发生故障时应该做什么。
*
* @author Kevin
* @Title: get
* @param id
* @return
* @return: String
*/
@GetMapping("/get1/{id}")
@HystrixCommand(fallbackMethod = "getError")
public String get1(@PathVariable String id) {
try {
System.out.println(Thread.currentThread().getName()+":get1 before sleep 5s....");
Thread.sleep(1000 * 5);
System.out.println(Thread.currentThread().getName()+":get1 after sleep 5s....");
} catch (InterruptedException e) {
e.printStackTrace();
}
return "kevin.get1." + id;
}
/**
* 配置Hystrix隔离策略，默认为THREAD，隔离策略分为THREAD、SEMAPHORE两种
*
* execution.isolation.strategy 默认为THREAD
*
* @param id
* @return
* @author lynch
*/
@GetMapping("/get2/{id}")
@HystrixCommand(fallbackMethod = "getError", commandProperties = {
// @HystrixProperty(name=HystrixPropertiesManager.EXECUTION_ISOLATION_STRATEGY, value="THREAD")
@HystrixProperty(name = HystrixPropertiesManager.EXECUTION_ISOLATION_STRATEGY, value = "SEMAPHORE") })
public String get2(@PathVariable String id) {
try {
System.out.println(Thread.currentThread().getName()+":get2 before sleep 5s....");
Thread.sleep(1000 * 5);
System.out.println(Thread.currentThread().getName()+":get2 after sleep 5s....");
} catch (InterruptedException e) {
e.printStackTrace();
}
return "kevin.get2." + id;
}
/**
* 设置HystrixCommand的执行是否在超时发生时被中断。使用线程隔离时，是否对命令执行超时的线程调用中断（Thread.interrupt()）操作
*
* execution.isolation.thread.interruptOnTimeout 参数,默认为true
*
* @param id
* @return
* @author lynch
*/
@GetMapping("/get3/{id}")
@HystrixCommand(fallbackMethod = "getError",commandProperties= {
//设置超时的时候不中断线程,默认为true
@HystrixProperty(name=HystrixPropertiesManager.EXECUTION_ISOLATION_THREAD_INTERRUPT_ON_TIMEOUT,value="false")
})
public String get3(@PathVariable String id) {
try {
System.out.println(Thread.currentThread().getName()+":get3 before sleep 5s....");
Thread.sleep(1000 * 5);
System.out.println(Thread.currentThread().getName()+":get3 after sleep 5s....");
} catch (InterruptedException e) {
e.printStackTrace();
}
return "kevin.get3." + id;
}
/**
* 设置调用线程产生的HystrixCommand.getFallback()方法的允许最大请求数目。 如果达到最大并发数目，后续请求将会被拒绝，如果没有实现回退，则抛出异常。
* (这里需要注意一点，这个变量的命名不是很规范，它实际上对THREAD和SEMAPHORE两种隔离策略都生效)
*
* fallback.isolation.semaphore.maxConcurrentRequests默认为10
*
* @param id
* @return
* @author lynch
*/
@GetMapping("/get4/{id}")
@HystrixCommand(fallbackMethod = "getError",commandProperties= {
@HystrixProperty(name = HystrixPropertiesManager.EXECUTION_ISOLATION_STRATEGY, value = "SEMAPHORE"),
@HystrixProperty(name=HystrixPropertiesManager.EXECUTION_ISOLATION_SEMAPHORE_MAX_CONCURRENT_REQUESTS,value="1")
})
public String get4(@PathVariable String id) {
try {
System.out.println(Thread.currentThread().getName()+":get4 before sleep 5s....");
Thread.sleep(1000 * 5);
System.out.println(Thread.currentThread().getName()+":get4 after sleep 5s....");
} catch (InterruptedException e) {
e.printStackTrace();
}
return "kevin.get4." + id;
}
/**
* 设置HystrixCommand的执行是否有超时限制。
*
* execution.timeout.enabled 默认为true, 是否超时
*
* @param id
* @return
*/
@GetMapping("/get5/{id}")
@HystrixCommand(fallbackMethod = "getError",commandProperties= {
@HystrixProperty(name=HystrixPropertiesManager.EXECUTION_TIMEOUT_ENABLED,value="false")
})
public String get5(@PathVariable String id) {
try {
System.out.println(Thread.currentThread().getName()+":get5 before sleep 5s....");
Thread.sleep(1000 * 5);
System.out.println(Thread.currentThread().getName()+":get5 after sleep 5s....");
} catch (InterruptedException e) {
e.printStackTrace();
}
return "kevin.get5." + id;
}
/**
* 设置调用者等待命令执行的超时限制，超过此时间，HystrixCommand被标记为TIMEOUT，并执行回退逻辑。
* 注意：超时会作用在HystrixCommand.queue()，即使调用者没有调用get()去获得Future对象。
*
* execution.isolation.thread.timeoutInMilliseconds 默认为1000
*
* @param id
* @return
* @author lynch
*/
@GetMapping("/get6/{id}")
@HystrixCommand(fallbackMethod = "getError",commandProperties= {
@HystrixProperty(name=HystrixPropertiesManager.EXECUTION_ISOLATION_THREAD_TIMEOUT_IN_MILLISECONDS,value="6000")
})
public String get6(@PathVariable String id) {
try {
System.out.println(Thread.currentThread().getName()+":get6 before sleep 5s....");
Thread.sleep(1000 * 5);
System.out.println(Thread.currentThread().getName()+":get6 after sleep 5s....");
} catch (InterruptedException e) {
e.printStackTrace();
}
return "kevin.get6." + id;
}
public String getError(String id) {
System.out.println(Thread.currentThread().getName()+":getError before ....");
myService.execute();
System.out.println(Thread.currentThread().getName()+":getError after ....");
return "超时错误,使用断路器返回" + id;
}
}