Seeking to achieve tomcat server push technology

I recently to be a project , use the tomcat server , the background using java, foreground Andrews , and now need to be a push technology that sends data back forward Taiwan initiative , will know what technology can achieve in this environment the push ? Thank you

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tomcat server to push data, it may well realize that our company andriod data on the system is through the socket connection , subscription data to achieve data update , do not know meet your asked not
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Some time ago , I also made ​​a push stuff about android , but in a push on the transformation of open source projects ,
reference to this : http://www.189works.com/article-54321-1.html
I hope for your help.
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android push on more mature with XMPP (java implementation ) \ MQTT (PHP) \ C2MD ( Google )
I also recently studied on android push, push basic principle: the server and client to establish a long connection, the client regularly lost packets , service termination package unpack .
If you simply push information state , then you can go to the next mina, demand more complex words openfire, this is a java open source projects abroad
http://www.oschina.net/question/54100_29551

need mina , then you can provide some information , learning together

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this seems not,
only foreground to background request ,

reception to be a regular request, provide background request
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fact, even if you push back forward units , in fact, a polling operation or the server side , and browsers are regular requests is the same.
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is to serve client needs from time to time send a notification to the client 's needs of the class ? But since it has been positioning service , the client and the like, this behavior will naturally restricted it. Server is not easy to know the address of the client , even if they know the address , the client receives is not suitable for permanent installation mechanism ( not closed and can not guarantee that affect performance , unless merely conceptual "Client ")
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can be based on HTTP connections to achieve long push, but still requires a client connection is initiated , see:

http://blog.csdn.net/ldh911/article/details/7268879
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C / S mode is good , B / S mode is good , all the TCP client Xianxiang must server initiates a connection , the two sides have established a connection to transfer data .
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http://www.iteye.com/topic/1117043 this post helped me a lot , the younger brother has been initially completed the project , basically meet the requirements of the current test , just do not know how effective concurrent and connected to practice , still further improved, I hope to do the same project to help a friend .
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in fact, the best way to connect with the XMPP long , and now a lot of people do not understand the nonsense in it to influence others ah
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can use tomcat7.0.x the websocket
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tomcat7 have sample code, web socket, use html5 's long connection , ie does not support