RetryContext – Spring Retry

Spring Retry is a powerful library that helps you handle retrying operations in your Spring applications. To use Spring Retry with a custom RetryContext, you need to create a custom RetryContext and customize it according to your requirements. Below is an example of using Spring Retry with a custom RetryContext:

First, you need to add the Spring Retry dependency to your project’s build file. For Maven, you can add the following dependency:

<dependency>
    <groupId>org.springframework.retry</groupId>
    <artifactId>spring-retry</artifactId>
    <version>1.3.1</version> <!-- Use the latest version available -->
</dependency>

Create a custom RetryContext class. This class will hold the custom data you want to associate with each retry operation. Here’s an example:

import org.springframework.retry.RetryContext;

public class CustomRetryContext implements RetryContext {
    private final int customData;

    public CustomRetryContext(int customData) {
        this.customData = customData;
    }

    public int getCustomData() {
        return customData;
    }

    @Override
    public Object getAttribute(String name) {
        // Implement this method if you need to store additional attributes in the context.
        return null;
    }

    @Override
    public void setAttribute(String name, Object value) {
        // Implement this method if you need to store additional attributes in the context.
    }
}

Create a custom RetryContextFactory that creates instances of your custom RetryContext:

import org.springframework.retry.RetryContext;
import org.springframework.retry.RetryContextCache;
import org.springframework.retry.context.DefaultRetryContext;
import org.springframework.retry.context.RetryContextFactory;

public class CustomRetryContextFactory implements RetryContextFactory {
    private final RetryContextCache retryContextCache;

    public CustomRetryContextFactory(RetryContextCache retryContextCache) {
        this.retryContextCache = retryContextCache;
    }

    @Override
    public RetryContext open(RetryContext parent, Object o, Throwable throwable) {
        int customData = 0; // Set your custom data here
        return new DefaultRetryContext(parent, customData);
    }

    @Override
    public void close(RetryContext context) {
        // Implement any necessary cleanup logic here
    }
}

Configure Spring Retry with your custom RetryContextFactory in your Spring configuration:

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.retry.RetryContextCache;
import org.springframework.retry.annotation.EnableRetry;
import org.springframework.retry.policy.SimpleRetryPolicy;
import org.springframework.retry.support.RetryTemplate;

@Configuration
@EnableRetry
public class RetryConfig {

    @Bean
    public RetryContextFactory customRetryContextFactory(RetryContextCache retryContextCache) {
        return new CustomRetryContextFactory(retryContextCache);
    }

    @Bean
    public RetryTemplate retryTemplate(RetryContextFactory customRetryContextFactory) {
        RetryTemplate retryTemplate = new RetryTemplate();
        retryTemplate.setRetryContextCache(customRetryContextFactory);
        retryTemplate.setRetryPolicy(new SimpleRetryPolicy(3)); // Configure your retry policy here
        return retryTemplate;
    }
}

In this configuration, we’ve created a custom RetryContextFactory that uses the CustomRetryContext class to hold custom data. We then configure a RetryTemplate with a custom retry context factory and retry policy.

Now you can use this custom retry template in your service methods or wherever you need to handle retries with custom contexts:

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.retry.RetryCallback;
import org.springframework.retry.support.RetryTemplate;
import org.springframework.stereotype.Service;

@Service
public class MyService {
    private final RetryTemplate retryTemplate;

    @Autowired
    public MyService(RetryTemplate retryTemplate) {
        this.retryTemplate = retryTemplate;
    }

    public void myMethodWithRetry() {
        retryTemplate.execute((RetryCallback<Void, RuntimeException>) retryContext -> {
            // Your code here
            int customData = ((CustomRetryContext) retryContext).getCustomData();
            // Perform the operation using customData
            // If an exception is thrown, the operation will be retried according to the configured policy
            return null;
        });
    }
}

In this example, the myMethodWithRetry method uses the custom retry template and accesses the custom data stored in the retry context.

Remember to configure the retry policy and any other retry-related settings according to your specific requirements in the RetryConfig class.

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