Jedis 1.0.0 版 源码分析系列2：Connection.java

package redis.clients.jedis;

import redis.clients.util.RedisInputStream;
import redis.clients.util.RedisOutputStream;

import java.io.*;
import java.net.Socket;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.List;

public class Connection {
    private String host;//ip
    private int port = Protocol.DEFAULT_PORT;//端口
    private Socket socket;//socket句柄
    private Protocol protocol = new Protocol();//具体操作对象
    private RedisOutputStream outputStream;//socket的输出流
    private RedisInputStream inputStream;//socket的输入流
    private int pipelinedCommands = 0;//管道命令计数器
    private int timeout = 2000;//socket超时时间

    public int getTimeout() {//获取socket超时时间
	return timeout;
    }

    public void setTimeout(int timeout) {//设置socket超时时间
	this.timeout = timeout;
    }

    public void setTimeoutInfinite() {//设置无穷大超时时间
	try {
	    socket.setSoTimeout(0);
	} catch (SocketException ex) {
	    throw new JedisException(ex);
	}
    }

    public void rollbackTimeout() {//回滚超时时间设置
	try {
	    socket.setSoTimeout(timeout);
	} catch (SocketException ex) {
	    throw new JedisException(ex);
	}
    }

    public Connection(String host) {//够早一个connection
	super();
	this.host = host;
    }

    protected Connection sendCommand(String name, String... args) {
		try {
			connect();//连接server
		} catch (UnknownHostException e) {
			throw new JedisException("Could not connect to redis-server", e);
		} catch (IOException e) {
			throw new JedisException("Could not connect to redis-server", e);
		}
	protocol.sendCommand(outputStream, name, args);//发送命令
	pipelinedCommands++;//增加计数器
	return this;
    }

    public Connection(String host, int port) {//构造connection
	super();
	this.host = host;
	this.port = port;
    }

    public String getHost() {//获取IP
	return host;
    }

    public void setHost(String host) {//设置IP
	this.host = host;
    }

    public int getPort() {//获取端口
	return port;
    }

    public void setPort(int port) {//设置端口
	this.port = port;
    }

    public Connection() {//构造connection
    }

    public void connect() throws UnknownHostException, IOException {
	if (!isConnected()) {//如果没有连接，才会连接对方并且给本地变量赋值
	    socket = new Socket(host, port);
	    socket.setSoTimeout(timeout);
	    outputStream = new RedisOutputStream(socket.getOutputStream());
	    inputStream = new RedisInputStream(socket.getInputStream());
	}
    }

    public void disconnect() {//断开连接
	if (isConnected()) {
	    try {
		inputStream.close();
		outputStream.close();//关闭流
		if (!socket.isClosed()) {
		    socket.close();
		}//关闭socket.
	    } catch (IOException ex) {
		throw new JedisException(ex);
	    }
	}
    }

    public boolean isConnected() {//判断是否连接上了
	return socket != null && socket.isBound() && !socket.isClosed()
		&& socket.isConnected() && !socket.isInputShutdown()
		&& !socket.isOutputShutdown();
    }

    protected String getStatusCodeReply() {//获取响应
	pipelinedCommands--;
	return (String) protocol.read(inputStream);
    }

    public String getBulkReply() {//获取响应
	pipelinedCommands--;
	return (String) protocol.read(inputStream);
    }

    public int getIntegerReply() {//获取响应
	pipelinedCommands--;
	return ((Integer) protocol.read(inputStream)).intValue();
    }

    @SuppressWarnings("unchecked")
    public List<String> getMultiBulkReply() {//获取响应
	pipelinedCommands--;
	return (List<String>) protocol.read(inputStream);
    }

    @SuppressWarnings("unchecked")
    public List<Object> getObjectMultiBulkReply() {//获取响应
	pipelinedCommands--;
	return (List<Object>) protocol.read(inputStream);
    }

    public List<Object> getAll() {//批量获取响应
	List<Object> all = new ArrayList<Object>();
	while (pipelinedCommands > 0) {
	    all.add(protocol.read(inputStream));
	    pipelinedCommands--;
	}
	return all;
    }
}

这个函数很有意思。

public boolean isConnected() {//判断是否连接上了
	return socket != null && socket.isBound() && !socket.isClosed()
		&& socket.isConnected() && !socket.isInputShutdown()
		&& !socket.isOutputShutdown();
    }