Is Connector thread safe?

Suite and Optimus Suite 5
#1

I read a discussion about the thread safety of BaseConnector - Tim Huang commented that it’s not thread safe. From my read of the code, he seems right. Here is his comment:

docs.dhtmlx.com/doku.php?id=dhtm … 125941acb3

I wonder if there is any new code addressing thread safety? It would be great if somebody can comment on this issue. Many thanks!

#2

In February we will release updated version.
You can try it now - the attached jar file has full backward compatibility, and in addition to other updates allow to create thread safe connectors

[code] public class Grid_01_BasicConnector_TS extends ThreadSafeConnectorServlet {

	@Override
	protected void configure(HttpServletRequest req, HttpServletResponse res) {
		
		Connection conn = ( new DataBaseConnection()).getConnection();
		
		GridConnector c = new GridConnector(conn);
		c.servlet(req,res);
		c.dynamic_loading(100);
		c.render_table("grid50000", "item_id", "item_nm,item_cd");
		
	}
}[/code]

a) use ThreadSafeConnectorServlet as base class
b) one extra command is required during connector init - c.servlet(req,res);
dhtmlxconnector.zip (163 KB)

#3

Hi,
I am using ThreadSafeConnector instead of connector servlet, till now everything is fine , but when I am trying to add the data the servlet is throwing some exception.I am not able to solve.Pls help me in this regard.Here is the stack trace of it.
java.lang.ClassCastException: com.dhtmlx.connector.GridConnector cannot be cast to com.dhtmlx.connector.CommonConnector
com.dhtmlx.connector.DataProcessor.get_status(DataProcessor.java:158)
com.dhtmlx.connector.DataProcessor.process(DataProcessor.java:120)
com.dhtmlx.connector.BaseConnector.render(BaseConnector.java:292)
com.dhtmlx.connector.BaseConnector.render_table(BaseConnector.java:210)
com.dhtmlx.connector.BaseConnector.render_table(BaseConnector.java:178)
com.kentropy.dhtmlxConnector.DhtmlxConnector.configure(DhtmlxConnector.java:29)
com.dhtmlx.connector.ThreadSafeConnectorServlet.doGet(ThreadSafeConnectorServlet.java:18)
com.dhtmlx.connector.ThreadSafeConnectorServlet.doPost(ThreadSafeConnectorServlet.java:25)
javax.servlet.http.HttpServlet.service(HttpServlet.java:647)

Thankyou,
Ravi.

#4

Above message is quite strange

a) there is no any type casting at line 158 in DataProcessor.java
b) event if it was here - the CommonConnector is a base class for GridConnector, so casting must not be a problem.

Which java server you are using?

#5

I am using apache tomcat 5.5 and jdk 1.5 .Here is the code snippet of how I am using the Threadsafeconnector.

public class DynamicLoader extends ThreadSafeConnectorServlet {

  @Override
  protected void configure(HttpServletRequest req, HttpServletResponse res) {
     
     Connection conn = DBConnection.getConnection();
     
     GridConnector gc = new GridConnector(conn);
     gc.servlet(req,res);
     gc.dynamic_loading(50);
     gc.render_table("accounts", "id", "usernam,password");
     
  }

}

#6

The init code is correct as well.

The connector.jar in the package was compiled against jdk 1.6 ( and tested with Tomcat, by the way ) - so maybe you need to recompile it against jdk 1.5 to resolve that problem ( not sure ). Jar file contains all sources inside.

#7

I’ve compiled dhtmlxconnector.jar with jdk 1.5 , It solved my issue.Thank you very much.