Retrieve BPEL process instances with Java

As mentioned in a previous article calling a process from java can be done easy. From another perspective, you need in the application the state of a particular process or process-instance. In the next example the java code is searching for a particular process that is running and retrieves his status.

The status of running process is the name of the current scope the process is in. To test the Java program creat a BPEL process with some scopes. Each scope is waiting of a few minutes. Running the Java program multiple times, results that you see that the status of the process is chaning.
Note: The article is based on this article, using the properties file and libraries.

The program:

RMIListInstances.java

package nl.orasoa.bpel;

import com.collaxa.xml.XMLHelper;

import com.oracle.bpel.client.BPELProcessId;
import com.oracle.bpel.client.IBPELProcessHandle;
import com.oracle.bpel.client.IInstanceHandle;
import com.oracle.bpel.client.Locator;
import com.oracle.bpel.client.NormalizedMessage;
import com.oracle.bpel.client.delivery.IDeliveryService;

import com.oracle.bpel.client.util.WhereCondition;

import com.oracle.bpel.client.util.WhereConditionHelper;

import java.util.Map;
import java.util.Properties;

import org.w3c.dom.Element;

public class RMIListInstances
{
public static void main(String[] args)
 throws Exception
{
 IInstanceHandle[] instHandles;
 IBPELProcessHandle[] procHandles;

 IInstanceHandle instance = null;
 BPELProcessId bpid = null;

 WhereCondition cond;
 WhereCondition cond1;
 WhereCondition cond2;

 try
 {
   // properties in the classpath
   Properties props = new java.util.Properties();

   // read the properties file
   java.net.URL url =
     ClassLoader.getSystemResource("context.properties");
   props.load(url.openStream());
   System.out.println(props);

// WhereCondition cond =
//        WhereConditionHelper.whereInstancesClosed();
// WhereCondition cond =
//        WhereConditionHelper.whereInstancesCompleted();
   // Search only open instances
   cond = WhereConditionHelper.whereInstancesOpen();

   // append where clause to search for
   // a specific process and version
   cond1 = new WhereCondition( "process_id = ?" );
   cond1.setString(1, "Wacht");
   cond2 = new WhereCondition( "revision_tag = ?" );
   cond2.setString(1, "1.0");

   // append the whole where clause  
   cond.append("and").append(cond1).append("and").append(cond2);

   // get a connection to the server
   Locator locator = new Locator("default", "welcome1", props);

   instHandles = locator.listInstances(cond);
   for (int j = 0; j < instHandles.length; j++)
   {
     // get the instance
     instance = instHandles[j];
     // get the process for the instance
     bpid = instance.getProcess().getProcessId();
     System.out.print("Got process " + bpid.getProcessId() 
                       + "("+ bpid.getRevisionTag() + ") ");
     System.out.println(instance.getConversationId() + " " 
         + instance.getStatus() + " " + instance.getTitle());
   }
 }
 catch (Exception e)
 {
   e.printStackTrace();
 }
}
}