import org.apache.hadoop.hdfs.protocolPB.NamenodeProtocolTranslatorPB; //导入依赖的package包/类
private static NamenodeProtocol createNNProxyWithNamenodeProtocol(
    InetSocketAddress address, Configuration conf, UserGroupInformation ugi,
    boolean withRetries) throws IOException {
  NamenodeProtocolPB proxy = (NamenodeProtocolPB) createNameNodeProxy(
      address, conf, ugi, NamenodeProtocolPB.class);
  if (withRetries) { // create the proxy with retries
    RetryPolicy timeoutPolicy = RetryPolicies.exponentialBackoffRetry(5, 200,
            TimeUnit.MILLISECONDS);
    Map<String, RetryPolicy> methodNameToPolicyMap
         = new HashMap<String, RetryPolicy>();
    methodNameToPolicyMap.put("getBlocks", timeoutPolicy);
    methodNameToPolicyMap.put("getAccessKeys", timeoutPolicy);
    NamenodeProtocol translatorProxy =
        new NamenodeProtocolTranslatorPB(proxy);
    return (NamenodeProtocol) RetryProxy.create(
        NamenodeProtocol.class, translatorProxy, methodNameToPolicyMap);
  } else {
    return new NamenodeProtocolTranslatorPB(proxy);
  }
}
 

import org.apache.hadoop.hdfs.protocolPB.NamenodeProtocolTranslatorPB; //导入依赖的package包/类
private static NamenodeProtocol createNNProxyWithNamenodeProtocol(
    InetSocketAddress address, Configuration conf, UserGroupInformation ugi,
    boolean withRetries) throws IOException {
  NamenodeProtocolPB proxy = (NamenodeProtocolPB) createNameNodeProxy(
      address, conf, ugi, NamenodeProtocolPB.class, 0);
  if (withRetries) { // create the proxy with retries
    RetryPolicy timeoutPolicy = RetryPolicies.exponentialBackoffRetry(5, 200,
            TimeUnit.MILLISECONDS);
    Map<String, RetryPolicy> methodNameToPolicyMap
         = new HashMap<String, RetryPolicy>();
    methodNameToPolicyMap.put("getBlocks", timeoutPolicy);
    methodNameToPolicyMap.put("getAccessKeys", timeoutPolicy);
    NamenodeProtocol translatorProxy =
        new NamenodeProtocolTranslatorPB(proxy);
    return (NamenodeProtocol) RetryProxy.create(
        NamenodeProtocol.class, translatorProxy, methodNameToPolicyMap);
  } else {
    return new NamenodeProtocolTranslatorPB(proxy);
  }
}
 

import org.apache.hadoop.hdfs.protocolPB.NamenodeProtocolTranslatorPB; //导入依赖的package包/类
@Test
public void testNamenodeProtocol() throws IOException {
  NamenodeProtocolTranslatorPB translator =
      (NamenodeProtocolTranslatorPB) NameNodeProxies.createNonHAProxy(conf,
          nnAddress, NamenodeProtocol.class, UserGroupInformation.getCurrentUser(),
          true).getProxy();
  boolean exists = translator.isMethodSupported("rollEditLog");
  assertTrue(exists);
  exists = translator.isMethodSupported("bogusMethod");
  assertFalse(exists);
}