在VC环境下，创建虚拟机对象，进而调用Java类，实现预先定义好的连接Cassandra数据库功能，满足某种业务需要

首先定义连接Cassandra的Java代码，包含插入、查询功能

import java.nio.ByteBuffer;
import java.nio.charset.Charset;
import java.util.List;

import org.apache.cassandra.thrift.Cassandra;
import org.apache.cassandra.thrift.Cassandra.Client;
import org.apache.cassandra.thrift.Column;
import org.apache.cassandra.thrift.ColumnOrSuperColumn;
import org.apache.cassandra.thrift.ColumnParent;
import org.apache.cassandra.thrift.ColumnPath;
import org.apache.cassandra.thrift.ConsistencyLevel;
import org.apache.cassandra.thrift.InvalidRequestException;
import org.apache.cassandra.thrift.KeyRange;
import org.apache.cassandra.thrift.KeySlice;
import org.apache.cassandra.thrift.NotFoundException;
import org.apache.cassandra.thrift.SlicePredicate;
import org.apache.cassandra.thrift.SliceRange;
import org.apache.cassandra.thrift.TimedOutException;
import org.apache.cassandra.thrift.UnavailableException;
import org.apache.thrift.TException;
import org.apache.thrift.protocol.TBinaryProtocol;
import org.apache.thrift.protocol.TProtocol;
import org.apache.thrift.transport.TFramedTransport;
import org.apache.thrift.transport.TSocket;
import org.apache.thrift.transport.TTransport;
import org.apache.thrift.transport.TTransportException;

public class Cassandratest{

	public static String KEYSPACE = "NDOUTILS";
	public static String HOST = "172.16.0.204";
	public static int PORT = 9160;
	public static String COLUMN_FAMILY = "logentries";

	private static Client client;
	private static TSocket socket;
	private static TTransport transport;
	private static TProtocol protocol;
	private boolean isOpen = false;
	
	public static void main(String args[]){
		Cassandratest ccl = new Cassandratest();
		ccl.init();
		ccl.end();
	}

	Cassandratest(String keyspace, String column_family, String host,
			int port) {
		// TODO Auto-generated constructor stub
		KEYSPACE = keyspace;
		COLUMN_FAMILY = column_family;
		HOST = host;
		PORT = port;
	}

	Cassandratest() {

	}

	private static ByteBuffer strToBB(String msg) {
		Charset charset = Charset.forName("UTF-8");
		return ByteBuffer.wrap(msg.getBytes(charset));
	}

	private static String byteToStr(byte[] buf) {
		Charset charset = Charset.forName("UTF-8");
		return new String(buf, charset);
	}

	private void init() {
		try {
			socket = new TSocket(HOST, PORT);
			transport = new TFramedTransport(socket);
			protocol = new TBinaryProtocol(transport);
			client = new Cassandra.Client(protocol);
		} catch (Exception e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}

		if (!isOpen) {
			try {
				transport.open();
				client.set_keyspace(KEYSPACE);
				System.out.println("Opening...OK");
			} catch (TTransportException e) {
				// TODO Auto-generated catch block
				System.out.println("Network is unreachable...");
			} catch (InvalidRequestException e) {
				// TODO Auto-generated catch block
				System.out.println("请求无效");
			} catch (TException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			isOpen = true;
			// insertNewColumn(COLUMN_FAMILY, "logentry_id", "value", "0000");
		} else {
			System.out.println("连接已经打开");
		}
	}

	private void end(){
		if (isOpen) {
			try {
				transport.flush();
				transport.close();
				System.out.println("Closing...OK");
			} catch (TTransportException e) {
				// TODO Auto-generated catch block
				System.out.println("Network is unreachable...");
			}
		} else {
			System.out.println("连接已经关闭");
		}
	}

	@SuppressWarnings("unused")
	private Column insertNewColumn(String ColumnFamily, String Field,
			String Name, String Value) {
		long timestamp = System.currentTimeMillis();
		Column column = new Column(strToBB(Name));
		column.setValue(strToBB(Value));
		column.setTimestamp(timestamp);
		try {
			client.insert(strToBB(Field), new ColumnParent(ColumnFamily),
					column, ConsistencyLevel.ONE);
			return c