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← Timeout | Retry(中文) | Error Handling →

Retries

Default

  • autoRetry: true
  • minRetryDelayMs: 300
  • maxRetryDelayMs: 300 * 1000
  • retryCondition: com.volcengine.retryer.DefaultRetryCondition
  • backoffStrategy: com.volcengine.retryer.ExponentialBackoffStrategy
  • retryErrorCode: empty set

The SDK retries on network errors and throttling. Business logic errors are not retried.

Retry Code Configuration

import com.volcengine.ApiClient;
import com.volcengine.retryer.DefaultRetryCondition;
import com.volcengine.retryer.ExponentialBackoffStrategy;
import com.volcengine.sign.Credentials;

public class SampleCode {
    public static void main(String[] args) {
        String region = "cn-beijing";

        ApiClient apiClient = new ApiClient()
            .setCredentials(Credentials.getEnvCredentials())
            .setRegion(region)
            .setDebugging(true)
            .setAutoRetry(true)
            .setNumMaxRetries(3)
            .setMinRetryDelayMs(1000)
            .setMaxRetryDelayMs(3000)
            .setRetryCondition(new DefaultRetryCondition())
            .setBackoffStrategy(new ExponentialBackoffStrategy())
            .addRetryErrorCode("InvalidAuthorization");
    }
}

Retry Conditions

Retry conditions define which situations should trigger a retry. The SDK includes a default retry condition, and users can also customize retry conditions based on their business needs.

Default Retry Conditions

The default retry condition DefaultRetryCondition includes the following:

  1. Retry on network errors.
  2. Retry on server throttling errors.
  3. Retry on user-specified error codes (retryErrorCodes).

Custom Retry Conditions

Users can customize retry conditions based on their business needs.

Code Example:

  1. Extend the base class RetryCondition and implement boolean shouldRetry(ApiResponse response, Exception error):

    import com.volcengine.retryer.RetryCondition;

public abstract class CustomRetryCondition extends RetryCondition {
    @Override
    public boolean shouldRetry(ApiResponse response, Exception error) {
        // Implement your own logic
        return false;
    }
}

  2. Reuse the default DefaultRetryCondition logic:

    import com.volcengine.retryer.DefaultRetryCondition;

public class CustomRetryCondition extends DefaultRetryCondition{
    @Override
    public boolean shouldRetry(ApiResponse response, Exception error) {
        boolean shouldRetry = super.shouldRetry(response, error);
        // Implement your own logic
        return false;
    }

}

Backoff Strategy

The backoff strategy defines the delay between each retry attempt. The SDK includes built-in backoff strategies, and users can also customize their own based on their needs.

Default

ExponentialWithRandomJitterBackoffStrategy

Built-in Strategies

Boundary values: minRetryDelay (min delay), maxRetryDelay (max delay), n is the retry count.

Name Description Formula
NoBackoffStrategy No backoff, retry immediately. delay = 0.0
ExponentialBackoffStrategy Exponential backoff with bounds. delay = min(minRetryDelay * 2ⁿ, maxRetryDelay)
ExponentialWithRandomJitterBackoffStrategy Exponential with jitter; value lies in [base, 2·base]. base = min(minRetryDelay · 2ⁿ, maxRetryDelay)
delay = base + U(0, base)

Custom Backoff Strategy

Users can customize their own backoff strategy based on their needs.

Code Example:

  1. Extend the base class BackoffStrategy and implement public long computeDelay(int retryCount):

    import com.volcengine.retryer.BackoffStrategy;

class CustomBackoffStrategy extends BackoffStrategy {
    public long computeDelay(int retryCount){
        long minRetryDelayMs = this.minRetryDelayMs;
        long maxRetryDelayMs = this.maxRetryDelayMs;
        // Implement your own logic
        return 0;
    }
}

  2. You can also reuse a built-in backoff strategy such as ExponentialBackoffStrategy or ExponentialWithRandomJitterBackoffStrategy:

    import com.volcengine.retryer.ExponentialWithDecayBackoffStrategy;

class CustomBackoffStrategy extends ExponentialWithDecayBackoffStrategy{
    public long computeDelay(int retryCount){
        long base = super.computeDelay(retryCount); // Call the parent implementation
        long minRetryDelayMs = this.minRetryDelayMs;
        long maxRetryDelayMs = this.maxRetryDelayMs;
        // Implement your own logic
        return 0;
    }
}

← Timeout | Retry(中文) | Error Handling →