Unique Key Violation on PUBLIC.ORGANIZATIONALENTITY when running processes concurrently

Issue

• When running processes concurrently, for example, by using the following code, an Unique Key Violation error is thrown:

  ExecutorService exec = Executors.newCachedThreadPool();
  exec.submit(new Runnable(){
      @Override
      public void run() {
          // start a new process instance
          ProcessInstance proc = ksession.startProcess("com.example.bpms.simplesupplyitemapproval", params);
  });
  exec.submit(new Runnable(){
      @Override
      public void run() {
      // start a new process instance
      ProcessInstance proc = ksession.startProcess("com.example.bpms.simplesupplyitemapproval", params); 
      }
  });
  

• When running processes concurrently, the following exception is thrown:

  ERROR: Unique index or primary key violation: "PRIMARY_KEY_C6 ON PUBLIC.ORGANIZATIONALENTITY(ID)"; SQL statement:
  insert into OrganizationalEntity (DTYPE, id) values ('User', ?) [23505-168]