基于Mozilla Thunderbird的扩展开发（六）---进程间通信之Socket篇（下）

Mozilla扩展系列链接： 1，浅谈基于Mozilla Thunderbird的扩展开发 2，基于Mozilla平台的扩展开发（续）----XPCOM组件篇 3，基于Mozilla Thunderbird的扩展开发（三）---如何获取邮件的完整信息 4，基于Mozilla Thunderbird的扩展开发（四）---修改源代码实现自动保存附件 5，基于Mozilla Thunderbird的扩展开发（五）---进程间通信之Socket篇（上） 6，基于Mozilla Thunderbird的扩展开发（六）---进程间通信之Socket篇（下）

在上一篇《基于Mozilla Thunderbird的扩展开发（五）---进程间通信之Socket篇（上）》中开发了一个简单的TCP服务器，本文将介绍其对应的客户端。

客户端代码：

consttBirdBiffClientUi =
{
tBirdBiffClientOnLoad:function()
{
//removetoavoidduplicateinitialization
removeEventListener("load",tBirdBiffClientUi.tBirdBiffClientOnLoad,true);
//初始化客户端
varclient=Components.classes["@phinecos.cnblogs.com/TBbiff/client;1"].getService(Components.interfaces.nsISupports).wrappedJSObject;
client.initialize();
varwindowCount=client.getWindowCollection().Count();
client.addWindow(window);
client=null;
tBirdBiffClientObserver.updateUi();//更新UI
//registerfornotifications
varservice=Components.classes["@mozilla.org/observer-service;1"].getService(Components.interfaces.nsIObserverService);
service.addObserver(tBirdBiffClientObserver,"thunderbirdBiff.uiUpdate",false);//加入监控者
service=null;
},

tBirdBiffClientOnClose:function()
{
//removetoavoidduplicateinitialization
removeEventListener("close",tBirdBiffClientUi.tBirdBiffClientOnClose,true);
varservice=Components.classes["@mozilla.org/observer-service;1"].getService(Components.interfaces.nsIObserverService);
service.removeObserver(tBirdBiffClientObserver,"thunderbirdBiff.uiUpdate");//移除监控者
service=null;

varclient=Components.classes["@phinecos.cnblogs.com/TBbiff/client;1"].getService(Components.interfaces.nsISupports).wrappedJSObject;
client.removeWindow(window);//移除窗口
client=null;
}
}
addEventListener( " load " ,tBirdBiffClientUi.tBirdBiffClientOnLoad, true );
addEventListener( " close " ,tBirdBiffClientUi.tBirdBiffClientOnClose, true );

客户类：

constCI = Components.interfaces,CC = Components.classes,CR = Components.results;
tBirdBiffClient.classID = Components.ID( " {5b0bccd0-83b9-11db-9fe1-0800200c9a66} " );
tBirdBiffClient.contractID = " @phinecos.cnblogs.com/TBbiff/client;1 " ;
tBirdBiffClient.classDescription = " BiffClientService " ;

function tBirdBiffClient()
{
this.timer=CC["@mozilla.org/timer;1"].getService(CI.nsITimer);//定时器
this.interval=null;//定时器时间间隔
this.socketTransport=null;
this.biffState=null;//邮箱状态
this.socket=null;//socket对象
this.input=null;//输入流
this.port=null;//服务器端口
this.hostname=null;//服务器主机名称
this.windowCollection=CC["@mozilla.org/supports-array;1"].createInstance(CI.nsICollection);//客户端窗口集合
this.initialized=false;//是否已经初始化
}

tBirdBiffClient.prototype =
{
getConnection:function()
{
this.closeSocket();//关闭先前的连接
this.socket=this.socketTransport.createTransport(null,0,this.hostname,this.port,null);//创建socket连接
if(!this.socket)
{
return;
}
varstream=this.socket.openInputStream(CI.nsITransport.OPEN_BLOCKING|CI.nsITransport.OPEN_UNBUFFERED,0,0);//打开输入流,类型为阻塞式，无缓冲
if(!stream)
{
this.closeSocket();
return;
}
this.input=CC["@mozilla.org/scriptableinputstream;1"].createInstance(CI.nsIScriptableInputStream);
if(!this.input)
{
this.closeSocket();
return;
}
this.input.init(stream);//初始化输入流
},
closeSocket:function()
{//关闭socket连接
if(this.input)
{
this.input.close(null);
this.input=null;
}

if(this.socket)
{
this.socket.close(null);
this.socket=null;
}
},
currentEventQueue:function()
{//当前事件队列
varEQS=CC["@mozilla.org/event-queue-service;1"].getService(CI.nsIEventQueueService);
returnEQS.getSpecialEventQueue(EQS.CURRENT_THREAD_EVENT_QUEUE);
},
initialize:function()
{//初始化客户端
if(this.initialized)
{
return;
}

this.getIntervalPref();//获取时间间隔
this.hostname=this.utility.getHostnamePref();//获取主机名称
this.port=this.utility.getPortPref();//获取端口
this.socketTransport=CC["@mozilla.org/network/socket-transport-service;1"].getService(CI.nsISocketTransportService);
this.getConnection();//创建socket连接
this.timer.initWithCallback(tBirdBiffCheckMailCallback,1000,this.timer.TYPE_ONE_SHOT);//启动定时器监听来自服务器的响应
this.initialized=true;
},
updateUi:function(result)
{//更新客户端UI
varstate;
switch(result)
{
case"":
{
state="offline";
break;
}
case"0":
{
state="noMail";
break;
}
case"1":
{
state="newMail";
break;
}
case"-1":
{
state="error";
break;
}
default:
{
state="weirdness";
break;
}
}
this.biffState=state;
state=null;
varservice=CC["@mozilla.org/observer-service;1"].getService(CI.nsIObserverService);
service.notifyObservers(null,"thunderbirdBiff.uiUpdate",null);
service=null;
},
checkForMail:function()
{//检查是否有数据到来
this.timer.initWithCallback(tBirdBiffReadFromServerCallback,1000,this.timer.TYPE_ONE_SHOT);
},

readFromServer:function()
{//从服务器读取数据
if(!this.input)
{//还未初始化输入流
this.getConnection();
}
try
{
varresult=this.input.read(1);//读取数据
if(result.length==1)
{
this.updateUi(result);//更新状态
}
result=null;
}
catch(e)
{
this.getConnection();
this.updateUi("");
}
this.timer.initWithCallback(tBirdBiffCheckMailCallback,this.interval,this.timer.TYPE_ONE_SHOT);//设置定时器
},
}

客户端监听者，负责监视邮箱的状态变化和读取来自服务器端的数据:

consttBirdBiffReadFromServerCallback =
{
notify:function(timer)
{//从服务器读取数据
varclient=CC[tBirdBiffClient.contractID].getService(CI.nsISupports).wrappedJSObject;
client.readFromServer();
client=null;
}
}

consttBirdBiffCheckMailCallback =
{
notify:function(timer)
{//检查邮箱状态
varclient=CC[tBirdBiffClient.contractID].getService(CI.nsISupports).wrappedJSObject;
client.checkForMail();
client=null;
}
}

为了测试服务器和客户端，我们使用firefox作为客户端的载体，thunderbird作为服务器端载体，可以看到thunderbird的邮箱状态会定时传给firefox，从而使得后者能随之更新其状态。

Reference:

1， https://addons.mozilla.org/en-US/thunderbird/addon/3788