OkHttpClient 的簡單配置，包含重試，線程池

@Configuration
public class OkHttpConfig {@Bean("deSourceOkHttp")public OkHttpClient okHttpClient() {return new OkHttpClient.Builder().connectTimeout(60, TimeUnit.SECONDS).readTimeout(30, TimeUnit.SECONDS).writeTimeout(30, TimeUnit.SECONDS).addInterceptor(new SmartRetryInterceptor(3,1000,true)).connectionPool(new ConnectionPool(50, 1, TimeUnit.MINUTES)).addInterceptor(chain -> chain.proceed(chain.request().newBuilder().addHeader("Accept", "application/json").addHeader("Content-Type", "application/json").build())).build();}
}

重試

public class SmartRetryInterceptor implements Interceptor {private final int maxRetries;private final long baseDelayMs;private final boolean enableJitter;public SmartRetryInterceptor(int maxRetries, long baseDelayMs, boolean enableJitter) {this.maxRetries = maxRetries;this.baseDelayMs = baseDelayMs;this.enableJitter = enableJitter;}@Overridepublic Response intercept(Chain chain) throws IOException {Request request = chain.request();Response response = null;IOException exception = null;for (int i = 0; i <= maxRetries; i++) {try {response = chain.proceed(request);if (isSuccessfulOrShouldNotRetry(response)) {return response;}} catch (IOException e) {exception = e;}// 如果是冪等請求或滿足特定條件，才重試if (isIdempotent(request) && i < maxRetries) {long delay = baseDelayMs * (1 << i); // 指數退避if (enableJitter) {delay += new Random().nextInt((int) (baseDelayMs * 0.5));}try {Thread.sleep(delay);} catch (InterruptedException e) {Thread.currentThread().interrupt();throw new IOException("重試中斷", e);}} else {break;}}if (response != null) {return response;}throw exception;}private boolean isSuccessfulOrShouldNotRetry(Response response) {return response.isSuccessful() || !shouldRetry(response.code());}private boolean shouldRetry(int code) {return retryhttpCpde.containsKey(code);}private boolean isIdempotent(Request request) {String method = request.method();return "GET".equals(method) || "POST".equals(method) ;}}