@Recover is not working if @Retryable returns a value

Question

I am trying to implement retry logic. my code is working as expected until return type of retry method is void. the moment I change it to String, @Recover stops working.

 @Component
  public class AdapterImpl {
      int count = 0;

    @Retryable(include = {NullPointerException.class, IllegalStateException.class}, backoff = @Backoff(delay = 100, maxDelay = 101), maxAttempts = 5)
    public void retry(String foo) {
        System.out.println(foo + " " + count++);
        if (foo.equals("foo")) {
            throw new NullPointerException("foo");
        } else if (foo.equals("bar")) {
            throw new IllegalStateException("bar");
        }
//        return "hi";
    }

    @Recover
    public void connectionException(NullPointerException e) {
        System.out.println("Retry failure NullPointerException");
    }

    @Recover
    public void connectionException(IllegalStateException e) {
        System.out.println("Retry failure IllegalStateException");
    }
}

for both foo and bar, retry logic is working. logs as below

bar 0
bar 1
bar 2
bar 3
bar 4
Retry failure IllegalStateException

but when I change the return type of retry method to String, the @Recover method stops working.

@Retryable(include = {NullPointerException.class, IllegalStateException.class}, backoff = @Backoff(delay = 100, maxDelay = 101), maxAttempts = 5)
public String retry(String foo) {
    System.out.println(foo + " " + count++);
    if (foo.equals("foo")) {
        throw new NullPointerException("foo");
    } else if (foo.equals("bar")) {
        throw new IllegalStateException("bar");
    }
    return "hi";
}

logs are as below

bar 0
bar 1
bar 2
bar 3
bar 4
2020-04-26 23:28:30.800 ERROR 59644 --- [nio-8087-exec-3] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.retry.ExhaustedRetryException: Cannot locate recovery method; nested exception is java.lang.IllegalStateException: bar] with root cause

java.lang.IllegalStateException: bar

My build.gradle is

   plugins {
    id 'java'
    id 'org.springframework.boot' version '2.2.6.RELEASE'
    id 'io.spring.dependency-management' version '1.0.9.RELEASE'
}

group 'com.demo.web'
version '1.0-SNAPSHOT'

repositories {
    mavenCentral()
}

dependencies {
    compile 'org.springframework.boot:spring-boot-starter-web'
    compile 'org.springframework.retry:spring-retry'
    compile 'org.springframework:spring-aspects'
    compileOnly 'org.projectlombok:lombok'
    annotationProcessor 'org.projectlombok:lombok'
    testCompile group: 'junit', name: 'junit', version: '4.12'
}

what am I doing wrong?

have you also changed return type of recovery method to `String` ? — Ryuzaki L, Apr 26 '20 at 18:15
the `recover` field in @Retryable should fill you @Recover method name — 袁文涛, Apr 02 '21 at 07:57

score 8 · Accepted Answer · answered Apr 26 '20 at 18:20

There are certain rules using @Recover with spring @Retryable

Annotation for a method invocation that is a recovery handler.
A suitable recovery handler has a first parameter of type Throwable (or a subtype of Throwable) and a return value of the same type as the @Retryable method to recover from.
The Throwable first argument is optional (but a method without it will only be called if no others match).
Subsequent arguments are populated from the argument list of the failed method in order.

So make sure you have the matching recoverable method with above rules

 @Recover
public String connectionException(NullPointerException e, String foo) {
    System.out.println("Retry failure NullPointerException");
}

@Recover
public String connectionException(IllegalStateException e, String foo) {
    System.out.println("Retry failure IllegalStateException");
}

@Recover is not working if @Retryable returns a value

1 Answers1