Convert Aws sdk 2.2 Client core tests from groovy to java

[jaydeluca]

Related to #7195

[laurit]

could use something like

  @SuppressWarnings("unchecked")
  private static DynamoDbClient wrapClient(DynamoDbAsyncClient asyncClient) {
    return (DynamoDbClient)
        Proxy.newProxyInstance(
            DynamoDbClient.class.getClassLoader(),
            new Class<?>[] {DynamoDbClient.class},
            (proxy, method, args) -> {
              Method asyncMethod =
                  DynamoDbAsyncClient.class.getMethod(method.getName(), method.getParameterTypes());
              CompletableFuture<?> future =
                  (CompletableFuture<?>) asyncMethod.invoke(asyncClient, args);
              return future.get();
            });
  }

so that the parameters would not need to be duplicated between sync and async case. Async test could use Object response = call.apply(wrapClient(client)); Note that the response passed to validateOperationResponse won't be a Future any more with this.
Could generalize this to

  @SuppressWarnings("unchecked")
  protected static <T, U> T wrapClient(Class<T> syncClientClass, Class<U> asyncClientClass, U asyncClient) {
    return (T)
        Proxy.newProxyInstance(
            AbstractAws2ClientCoreTest.class.getClassLoader(),
            new Class<?>[] {syncClientClass},
            (proxy, method, args) -> {
              Method asyncMethod =
                  asyncClientClass.getMethod(method.getName(), method.getParameterTypes());
              CompletableFuture<?> future =
                  (CompletableFuture<?>) asyncMethod.invoke(asyncClient, args);
              return future.get();
            });
  }

from what I noticed only s3 getObject has different parameters for sync and async.
Idk if the slightly reduced code size is worth it.

[jaydeluca]

you are a wizard. thank you for this suggestion