1
<dependency>
2
     <groupId>com.alibaba.csp</groupId>
3
     <artifactId>sentinel-core</artifactId>
4
     <version>1.8.0</version>
5
</dependency>

1
@RestController
2
@Slf4j
3
public class HelloController {
4

5
    private static final String RESOURCE_NAME = "hello";
6

7
    @RequestMapping(value = "/hello")
8
    public String hello() {
9

10
        Entry entry = null;
11
        try {
12
            // 资源名可使用任意有业务语义的字符串，比如方法名、接口名或其它可唯一标识的字符串。
13
            entry = SphU.entry(RESOURCE_NAME);
14
            // 被保护的业务逻辑
15
            String str = "hello world";
16
            log.info("====="+str);
17
            return str;
18
        } catch (BlockException e1) {
19
            // 资源访问阻止，被限流或被降级
20
            //进行相应的处理操作
21
            log.info("block!");
22
        } catch (Exception ex) {
23
            // 若需要配置降级规则，需要通过这种方式记录业务异常
24
            Tracer.traceEntry(ex, entry);
25
        } finally {
26
            if (entry != null) {
27
                entry.exit();
28
            }
29
        }
30
        return null;
31
    }
32

33
    /**
34
     * 定义流控规则
35
     */
36
    @PostConstruct
37
    private static void initFlowRules(){
38
        List<FlowRule> rules = new ArrayList<>();
39
        FlowRule rule = new FlowRule();
40
        //设置受保护的资源
41
        rule.setResource(RESOURCE_NAME);
42
        // 设置流控规则 QPS
43
        rule.setGrade(RuleConstant.FLOW_GRADE_QPS);
44
        // 设置受保护的资源阈值
45
        // Set limit QPS to 20.
46
        rule.setCount(1);
47
        rules.add(rule);
48
        // 加载配置好的规则
49
        FlowRuleManager.loadRules(rules);
50
    }
51
}

1
<dependency>
2
    <groupId>com.alibaba.csp</groupId>
3
    <artifactId>sentinel-annotation-aspectj</artifactId>
4
    <version>1.8.0</version>
5
</dependency>

1
@Configuration
2
public class SentinelAspectConfiguration {
3

4
    @Bean
5
    public SentinelResourceAspect sentinelResourceAspect() {
6
        return new SentinelResourceAspect();
7
    }
8
}

1
@RequestMapping(value = "/findOrderByUserId/{id}")
2
@SentinelResource(value = "findOrderByUserId",
3
                  fallback = "fallback",fallbackClass = ExceptionUtil.class,
4
                  blockHandler = "handleException",blockHandlerClass = ExceptionUtil.class
5
                 )
6
public R  findOrderByUserId(@PathVariable("id") Integer id) {
7
    //ribbon实现
8
    String url = "http://mall-order/order/findOrderByUserId/"+id;
9
    R result = restTemplate.getForObject(url,R.class);
10

11
    if(id==4){
12
        throw new IllegalArgumentException("非法参数异常");
13
    }
14

15
    return result;
16
}

1
public class ExceptionUtil {
2

3
    public static R fallback(Integer id,Throwable e){
4
        return R.error(-2,"===被异常降级啦===");
5
    }
6

7
    public static R handleException(Integer id, BlockException e){
8
        return R.error(-2,"===被限流啦===");
9
    }
10
}

1
<dependency>
2
    <groupId>com.alibaba.csp</groupId>
3
    <artifactId>sentinel-transport-simple-http</artifactId>
4
    <version>1.8.0</version>
5
</dependency>

1
-Dcsp.sentinel.dashboard.server=consoleIp:port