Reliability

Definition

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Reliability Patterns

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Fault Tolerance Strategies

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Implementation

Retry with Exponential Backoff

public <T> T retryWithBackoff(Supplier<T> operation, int maxRetries) {
    int retries = 0;
    while (true) {
        try {
            return operation.get();
        } catch (Exception e) {
            if (++retries >= maxRetries) throw e;

            long waitTime = (long) Math.pow(2, retries) * 1000;
            long jitter = (long) (Math.random() * 1000);

            Thread.sleep(waitTime + jitter);
        }
    }
}

Circuit Breaker

public class CircuitBreaker {
    private State state = State.CLOSED;
    private int failureCount = 0;
    private long lastFailureTime;
    private final int threshold = 5;
    private final long timeout = 30000;

    public <T> T execute(Supplier<T> operation, Supplier<T> fallback) {
        if (state == State.OPEN) {
            if (System.currentTimeMillis() - lastFailureTime > timeout) {
                state = State.HALF_OPEN;
            } else {
                return fallback.get();
            }
        }

        try {
            T result = operation.get();
            reset();
            return result;
        } catch (Exception e) {
            recordFailure();
            return fallback.get();
        }
    }

    private void recordFailure() {
        failureCount++;
        lastFailureTime = System.currentTimeMillis();
        if (failureCount >= threshold) {
            state = State.OPEN;
        }
    }

    private void reset() {
        failureCount = 0;
        state = State.CLOSED;
    }
}

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Testing for Reliability

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Tips & Tricks

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