import org.apache.hadoop.metrics.spi.AbstractMetricsContext; //导入依赖的package包/类
@Test
public void testCloseShouldCloseTheSocketWhichIsCreatedByInit() throws Exception {
  AbstractMetricsContext context=new GangliaContext();
  context.init("gangliaContext", ContextFactory.getFactory());
  GangliaContext gangliaContext =(GangliaContext) context;
  assertFalse("Socket already closed",gangliaContext.datagramSocket.isClosed());
  context.close();
  assertTrue("Socket not closed",gangliaContext.datagramSocket.isClosed());
}
 

import org.apache.hadoop.metrics.spi.AbstractMetricsContext; //导入依赖的package包/类
/**
 * Only works in DEBUG level.
 * Prints the loaded .jar files at the start of Cygnus run.
 */
public static void printLoadedJars() {
    // trace the file containing the httpclient library
    URL myClassURL = PoolingClientConnectionManager.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading httpclient from " + myClassURL.toExternalForm());
    
    // trace the file containing the httpcore library
    myClassURL = DefaultBHttpServerConnection.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading httpcore from " + myClassURL.toExternalForm());
    
    // trace the file containing the junit library
    myClassURL = ErrorCollector.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading junit from " + myClassURL.toExternalForm());
    
    // trace the file containing the flume-ng-node library
    myClassURL =
            RegexExtractorInterceptorMillisSerializer.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading flume-ng-node from " + myClassURL.toExternalForm());
    
    // trace the file containing the libthrift library
    myClassURL = ListMetaData.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading libthrift from " + myClassURL.toExternalForm());
    
    // trace the file containing the gson library
    myClassURL = JsonPrimitive.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading gson from " + myClassURL.toExternalForm());
    
    // trace the file containing the json-simple library
    myClassURL = Yytoken.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading json-simple from " + myClassURL.toExternalForm());
    
    // trace the file containing the mysql-connector-java library
    myClassURL = Driver.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading mysql-connector-java from " + myClassURL.toExternalForm());
    
    // trace the file containing the postgresql library
    myClassURL = BlobOutputStream.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading postgresql from " + myClassURL.toExternalForm());
    
    // trace the file containing the log4j library
    myClassURL = SequenceNumberPatternConverter.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading log4j from " + myClassURL.toExternalForm());
    
    // trace the file containing the hadoop-core library
    myClassURL = AbstractMetricsContext.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading hadoop-core from " + myClassURL.toExternalForm());
    
    // trace the file containing the hive-exec library
    myClassURL = AbstractMapJoinOperator.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading hive-exec from " + myClassURL.toExternalForm());
    
    // trace the file containing the hive-jdbc library
    myClassURL = HivePreparedStatement.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading hive-jdbc from " + myClassURL.toExternalForm());
    
    // trace the file containing the mongodb-driver library
    myClassURL = AsyncReadWriteBinding.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading mongodb-driver from " + myClassURL.toExternalForm());
    
    // trace the file containing the kafka-clients library
    myClassURL = OffsetOutOfRangeException.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading kafka-clientsc from " + myClassURL.toExternalForm());
    
    // trace the file containing the zkclient library
    myClassURL = ZkNoNodeException.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading zkclient from " + myClassURL.toExternalForm());
    
    // trace the file containing the kafka_2.11 library
    myClassURL = KafkaMigrationTool.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading kafka_2.11 from " + myClassURL.toExternalForm());
    
    // trace the file containing the aws-java-sdk-dynamodb library
    myClassURL = WriteRequest.class.getProtectionDomain().getCodeSource().getLocation();
    LOGGER.debug("Loading aws-java-sdk-dynamodb from " + myClassURL.toExternalForm());

}