### Question:
ForwardingChannelBuilder extends ManagedChannelBuilder<T> { @Override public ManagedChannel build() { return delegate().build(); } protected  ForwardingChannelBuilder(); static ManagedChannelBuilder<?> forAddress(String name, int port); static ManagedChannelBuilder<?> forTarget(String target); @Override T directExecutor(); @Override T executor(Executor executor); @Override T intercept(List<ClientInterceptor> interceptors); @Override T intercept(ClientInterceptor... interceptors); @Override T userAgent(String userAgent); @Override T overrideAuthority(String authority); @Override @Deprecated T usePlaintext(boolean skipNegotiation); @Override T usePlaintext(); @Override T useTransportSecurity(); @Override T nameResolverFactory(NameResolver.Factory resolverFactory); @Override T loadBalancerFactory(LoadBalancer.Factory loadBalancerFactory); @Override T enableFullStreamDecompression(); @Override T decompressorRegistry(DecompressorRegistry registry); @Override T compressorRegistry(CompressorRegistry registry); @Override T idleTimeout(long value, TimeUnit unit); @Override T maxInboundMessageSize(int max); @Override T maxInboundMetadataSize(int max); @Override T keepAliveTime(long keepAliveTime, TimeUnit timeUnit); @Override T keepAliveTimeout(long keepAliveTimeout, TimeUnit timeUnit); @Override T keepAliveWithoutCalls(boolean enable); @Override T maxRetryAttempts(int maxRetryAttempts); @Override T maxHedgedAttempts(int maxHedgedAttempts); @Override T retryBufferSize(long bytes); @Override T perRpcBufferLimit(long bytes); @Override T disableRetry(); @Override T enableRetry(); @Override T setBinaryLog(BinaryLog binaryLog); @Override T maxTraceEvents(int maxTraceEvents); @Override ManagedChannel build(); @Override String toString();  }### Answer:
@Test public void buildReturnsDelegateBuildByDefualt() { ManagedChannel mockChannel = mock(ManagedChannel.class); doReturn(mockChannel).when(mockDelegate).build(); assertThat(testChannelBuilder.build()).isSameAs(mockChannel); }