Is there any kind of variable in JBPM4 like 'transient varia

[lixiangrjxy]

In jbpm3, we can use transient variables to process biz data between two wait nodes, is there the same kind of variable in JBPM4？ anyone who can advise?

[frantisek.kocun]

I was searching for the same in vain. But I use PVM with own language so I coded that myself.

If you find it please let us know!

Thanks

Fero

[shekharv]

http://www.jboss.org/index.html?module=bb&op=viewtopic&t=157927

[npirard]

Hello

I am not sure if I get the point here. I would like to forward a variable throughout some decisions but without persisting them (sensitive data that should not be in my DB)

could this idea of "transient variable" be what I am looking for?

but then I do not quite understand the thread shekharv is referring to : the variables set by ExecutionService are persisted, aren't they?

[kukeltje]

afaik, jBPM4 has no notion of transient variables. otoh, if you do not use anything async, you could use 'thread local' stuff.

[lixiangrjxy]

"kukeltje" wrote:
afaik, jBPM4 has no notion of transient variables. otoh, if you do not use anything async, you could use 'thread local' stuff.

Actually I'm using a ThreadLocal now, thank you for your suggestion. Indeed I think transient variable is useful and necessary for jbpm, I just wonder if there's any similar sulotions controled by jbpm, not by programmer

[lixiangrjxy]

"npirard" wrote:
Hello

I am not sure if I get the point here. I would like to forward a variable throughout some decisions but without persisting them (sensitive data that should not be in my DB)

could this idea of "transient variable" be what I am looking for?

but then I do not quite understand the thread shekharv is referring to : the variables set by ExecutionService are persisted, aren't they?

I think we're looking for the same thing. and I think it shekharv's sulotion is not what we want.

An util class and a ThreadLocal variable can be work here as npirard suggested.

[npirard]

in fact I made a quick test workaround yesterday using a Custom

I try to pack the code and post it here this day, I'd be glad if anyone could point a flaw in it, if any, or validate my "secret" parameter is not recorded in some JBPM table ;-)

the ThreadLocale idea is nice too, thanks

[kukeltje]

I have to be honest, the ThreadLocal thing was not fully my idea. As far as I remember, it is the way jBPM3 did it to :-)

[npirard]

well, jBPM3 had a nice idea, IMO :-)

especially if the transient data has to be used at several parts of the process, so that it is overall better than mine.



here is what I did, I pass the data when signalling the Custom that uses them with method
ExecutionService.signalExecutionById(String, String, Map<String, ?>)



JPDL :

<?xml version="1.0" encoding="UTF-8"?>

<process name="CustomParameters" xmlns="http://jbpm.org/4.0/jpdl">
 <start g="161,71,48,48" name="start1">
 <transition g="-30,-37" name="to input_some_info" to="input_some_info"/>
 </start>
 <state g="301,129,209,52" name="input_some_info">
 <transition g="-68,-18" name="to exclusive1" to="exclusive1"/>
 </state>
 <decision g="381,222,48,48" name="exclusive1">
 <handler class="org.jbpm.npi.Exclusive1Handler" />
 <transition g="-58,-18" name="to custom1" to="custom1"/>
 </decision>
 <custom class="org.jbpm.npi.MyCustom" g="361,319,92,52" name="custom1">
 <transition name="to exclusive2" to="exclusive2" g="-68,-18"/>
 </custom>
 <decision g="384,416,48,48" name="exclusive2">
 <handler class="org.jbpm.npi.Exclusive2Handler" />
 <transition name="to wait2" to="wait2" g="-44,-18"/>
 </decision>
 <end g="569,500,48,48" name="end1"/>
 <state name="wait2" g="350,479,92,52">
 <transition name="to end1" to="end1" g="-42,-18"/>
 </state>
</process>

two simple DecisionHandlers :

package org.jbpm.npi;

import org.jbpm.api.jpdl.DecisionHandler;
import org.jbpm.api.model.OpenExecution;

public class Exclusive1Handler implements DecisionHandler {

 @Override
 public String decide(OpenExecution arg0) {
 return "to custom1";
 }
}

package org.jbpm.npi;

import org.jbpm.api.jpdl.DecisionHandler;
import org.jbpm.api.model.OpenExecution;

public class Exclusive2Handler implements DecisionHandler {

 @Override
 public String decide(OpenExecution arg0) {
 return "to wait2";
 }
}

my Custom :

package org.jbpm.npi;

import java.util.Map;

import org.jbpm.api.activity.ActivityExecution;
import org.jbpm.api.activity.ExternalActivityBehaviour;

public class MyCustom implements ExternalActivityBehaviour {

 @Override
 public void signal(ActivityExecution activityExecution, String signal, Map<String, ?> parameters) throws Exception {
 System.out.println("signal() - ring the Kremlin !! " + parameters.get("putinPhoneNumber"));

 activityExecution.takeDefaultTransition();
 }

 @Override
 public void execute(ActivityExecution activityExecution) throws Exception {
 System.out.println("MyCustom.execute()");
 activityExecution.waitForSignal();
 }

}

the test class

package org.jbpm.npi;

import java.util.HashMap;
import java.util.Map;

import org.jbpm.api.Execution;
import org.jbpm.api.ProcessInstance;
import org.jbpm.test.JbpmTestCase;

/**
 * test the possibility to inject parameters at some point of a process without
 * persisting them
 *
 * @author npirard
 */
public class CustomParametersTest extends JbpmTestCase {

 String deploymentId;

 @Override
 protected void setUp() throws Exception {
 super.setUp();

 deploymentId = repositoryService.createDeployment().addResourceFromClasspath("org/jbpm/npi/CustomParameters.jpdl.xml").deploy();
 }

 @Override
 protected void tearDown() throws Exception {
 repositoryService.deleteDeploymentCascade(deploymentId);

 super.tearDown();
 }

 public void testProcess(){
 Map<String, Object> variables = new HashMap<String, Object>();

 //this is a variable that can be persisted without problem
 variables.put("publicInfo", "this is not really secret");
 ProcessInstance processInstance = executionService.startProcessInstanceByKey("CustomParameters", variables);

 Execution executionInA = processInstance.findActiveExecutionIn("input_some_info");
 assertNotNull(executionInA);

 processInstance = executionService.signalExecutionById(executionInA.getId());

 Execution executionInCustom = processInstance.findActiveExecutionIn("custom1");
 Map<String, String> parameters = new HashMap<String, String>();

 //this is really secret matter
 parameters.put("putinPhoneNumber", "[phone]");
 processInstance = executionService.signalExecutionById(executionInCustom.getId(), "mySignal", parameters);

 Execution executionInWait2 = processInstance.findActiveExecutionIn("wait2");

 assertNotNull(executionInWait2);// breakpoint A

 processInstance = executionService.signalExecutionById(executionInWait2.getId());

 assertTrue(processInstance.isEnded());// breakpoint B
 }
}

I executed it in debug ; at breakpoint A I found "publicInfo" in table JBPM4_VARIABLE, but not "putinPhoneNumber"

at breakpoint B I do not find anything in JBPM4_VARIABLE. By the way, I would have expected "publicInfo" in JBPM4_HIST_VAR, but it is not. Maybe I have not understood the purpose of this latter table : it is not supposed to record the variables of past executions?

[kukeltje]

The history table is exactly what you think it is for. There are just some things not implemented yet, see the jira for history issues.