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Thrift Java server OutOfMemoryError with Javascript client

I started learning thrift yesterday.

After much effort, I successfully completed a Java tutorial. Java server and client work fine.

But now I want the javascript client to communicate with the Java Thrift server.

To do this, I moved all the js files to a folder js/.

And paste the index.html code as below:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
  <title>Thrift Javascript Bindings - Tutorial Example</title>

  <script src="js/thrift.js"  type="text/javascript"></script>
  <script src="js/tutorial_types.js"    type="text/javascript"></script>
  <script src="js/shared_types.js"      type="text/javascript"></script>
  <script src="js/SharedService.js"     type="text/javascript"></script>
  <script src="js/Calculator.js"        type="text/javascript"></script>

  <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>


  <script type="text/javascript" charset="utf-8">
  //<![CDATA[
  $(document).ready(function(){
    // remove pseudo child required for valid xhtml strict
    $("#op").children().remove();
    // add operations to it dropdown menu
    $.each(Operation, function(key, value) {
      $('#op').append($("<option></option>").attr("value",value).text(key)); 
    });

     $('table.calculator').attr('width', 500);
  });

  function calc() {
    var transport = new Thrift.Transport("http://localhost:9090");
    var protocol  = new Thrift.Protocol(transport);
    var client    = new CalculatorClient(protocol);

    var work = new Work()
    work.num1 = $("#num1").val();
    work.num2 = $("#num2").val();
    work.op = $("#op").val();

    try {
      result = client.calculate(1, work);
      $('#result').val(result);
      $('#result').css('color', 'black');
    } catch(ouch){
      $('#result').val(ouch.why);
      $('#result').css('color', 'red');
    }
  }

  function auto_calc() {
    if ($('#autoupdate:checked').val() !== undefined) {
      calc();
    }
  }
  //]]>
  </script>

</head>
<body>
  <h2>Thrift Javascript Bindings</h2>
  <form action="">
  <table class="calculator">
    <tr>
      <td>num1</td>
      <td><input type="text" id="num1" value="20" onkeyup="javascript:auto_calc();"/></td>
    </tr>
    <tr>
      <td>Operation</td>
      <td><select id="op" size="1" onchange="javascript:auto_calc();"><option></option></select></td>
    </tr>
    <tr>
      <td>num2</td>
      <td><input type="text" id="num2" value="5" onkeyup="javascript:auto_calc();"/></td></tr>
    <tr>
      <td>result</td>
      <td><input type="text" id="result" value=""/></td></tr>
    <tr>
      <td><input type="checkbox" id="autoupdate" checked="checked"/>autoupdate</td>
      <td><input type="button" id="calculate" value="calculate" onclick="javascript:calc();"/></td>
    </tr>
  </table>
  </form>

  <p>This Java Script example uses <a href="https://git-wip-us.apache.org/repos/asf?p=thrift.git;a=blob;f=tutorial/tutorial.thrift;hb=HEAD">tutorial.thrift</a> and a Thrift server using JSON protocol and HTTP transport.
  </p>
    <p>
        <a href="http://validator.w3.org/check/referer"><img
            src="http://www.w3.org/Icons/valid-xhtml10"
            alt="Valid XHTML 1.0!" height="31" width="88" /></a>
    </p>
</body>
</html>

I replaced the string

var transport = new Thrift.Transport("/thrift/service/tutorial/");

with

var transport = new Thrift.Transport("http://localhost:9090");

Like, my server is on port 9090. And /thrift/service/tutorialit made no sense to me, nor did it work.

Then when I open the page.

Java server crashes with the following error:

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
    at org.apache.thrift.protocol.TBinaryProtocol.readStringBody(TBinaryProtocol.java:339)
    at org.apache.thrift.protocol.TBinaryProtocol.readMessageBegin(TBinaryProtocol.java:202)
    at org.apache.thrift.TBaseProcessor.process(TBaseProcessor.java:27)
    at org.apache.thrift.server.TSimpleServer.serve(TSimpleServer.java:83)
    at thrift.server.CalculatorServer.main(CalculatorServer.java:23)

Here is the java class CalculatorServer.

package thrift.server;

import org.apache.thrift.server.TServer;
import org.apache.thrift.server.TServer.Args;
import org.apache.thrift.server.TSimpleServer;
import org.apache.thrift.transport.TServerSocket;
import org.apache.thrift.transport.TServerTransport;
import org.apache.thrift.transport.TTransportException;

import tutorial.Calculator;

public class CalculatorServer {

    public static void main(String[] args) {
        CalculatorHandler handler = new CalculatorHandler();
        Calculator.Processor<CalculatorHandler> processor = new Calculator.Processor<>(handler);        

        try {
            TServerTransport serverTransport = new TServerSocket(9090);
            TServer server = new TSimpleServer(new Args(serverTransport).processor(processor));

            System.out.println("Starting the simple server...");
            server.serve();
        } catch (TTransportException e) {
            e.printStackTrace();
        }
    }

}

The rest of the code is used in the Thrift Tutorials. Actually, the Java Thrift server works great with the Java Thrift client. I don't think there are problems on the server side of Java.

- , ?

Javascript?

Java SE - . , , HTML + CSS + JS, Java Swing.

+3
3

javascript. , , , . , view.html http://localhost:8088/view.html . , Google . , .

  • Java- .

  • <dom-module id="thrift-client">
<template>
</template>
<script>
    Polymer({
        is:'thrift-client',
        ready:function(){
            var transport = new Thrift.TXHRTransport("http://localhost:8088/service");

            var protocol  = new Thrift.TJSONProtocol(transport);

            var client = new NtvApiClient(protocol);

            var result = client.ping(); // ping the java server. custom

            console.log(result);
        }

        });
</script>

  • , http://localhost http://Your_server_ip_address.

  • , java- ,

  • bravo, java- - javascript .

  • , u js.

                    var transport = new Thrift.TXHRTransport("http://localhost:8088/service");
                var protocol  = new Thrift.TJSONProtocol(transport);
                var client = new NtvApiClient(protocol);
                var result = client.ping();

    .

+2

"TTransport" HTTP. http , , -, js , "TTransport" http. "org.apache.thrift.server.TServlet", http .

"TJSONProtocol" "TBinaryProtocol" , siftift js . , .

public class CalculatorServlet extends TServlet 
{
   public CalculatorServlet() 
   {
      //'Calculator' is the generated class from thrift, 
      //'CalculatorHandler' is the implement class for thrift rpc
      super(new Calculator.Processor(
            new CalculatorHandler()),
            new TJSONProtocol.Factory());
  }
}
+1

IIRC, JavaScript JSON. () .

: JSON .

Thrift , / . :

  • HTTP-
  • JSON
  • < framed ( , )

(There are some exceptions, because some types of servers essentially require frames, but this is a whole different story and has nothing to do with your problem)

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