DWR: Easy Ajax for Java

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Writing JavaScript with DWR

DWR generates Javascript code that is similar to the Java code that exported using dwr.xml.

The biggest challenge in creating a remote interface to match some Java code across Ajax is the (usually) asynchronous nature of Ajax, compared to the synchronous nature of a normal Java call.

DWR solves this problem by introducing a callback function that is called when the data is returned from the server.

There are 2 recommended ways to make a call using DWR. Either using by appending a callback function to the parameter list or by appending a call meta data object.

It is also possible to put the callback function at the start of the parameter list, however this option is not advised because there are some issues when dealing with automatic http objects (see "Alternative Method"). This method mostly remains for backwards compatibility.