How to connect Process and Operator?

prayerslayer

Hello!

I'm very aware of the fact that it's not being welcomed to ask questions regarding the chaining of operators programatically. However, I need to do this for my thesis and hope that you'll kindly oversee it this time.

Everything works really well already, but I couldn't figure out how to connect the output of an operator to a result port of my process. Could anyone give me a hint? It's this part:



I tried to look for ports of the RootOperator, but there was no output:

System.out.println("looking for process ports");
for (String port : process.getRootOperator().getInputPorts().getPortNames())
	System.out.println(port);

Am I able to add it anyway? Or somewhere else?

The actual problem I have is that after the process finished, I can't access the result (because there is none, I guess).

INFO: Process finished successfully after 3 s
java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
	at java.util.ArrayList.rangeCheck(ArrayList.java:570)
	at java.util.ArrayList.get(ArrayList.java:348)
	at com.rapidminer.operator.IOContainer.getElementAt(IOContainer.java:112)
	at BackendTest.main(BackendTest.java:128)

At this line:

if (process_result.getElementAt(0) instanceof ExampleSet) { ... }

Thanks in advance!

Marco_Boeck

Hi,

you may ask whatever you want to know - we just encourage others to use the GUI approach because it is much easier. However if there's a reason why you need to do it programatically, it is perfectly fine

I put together a quick example for you:

This is the example process with an operator not connected to an output port.

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<process version="5.2.003">
  <context>
    <input/>
    <output/>
    <macros/>
  </context>
  <operator activated="true" class="process" compatibility="5.2.003" expanded="true" name="Process">
    <parameter key="logverbosity" value="init"/>
    <parameter key="random_seed" value="2001"/>
    <parameter key="send_mail" value="never"/>
    <parameter key="notification_email" value=""/>
    <parameter key="process_duration_for_mail" value="30"/>
    <parameter key="encoding" value="SYSTEM"/>
    <parameter key="parallelize_main_process" value="false"/>
    <process expanded="true" height="639" width="950">
      <operator activated="true" class="retrieve" compatibility="5.2.003" expanded="true" height="60" name="Retrieve" width="90" x="45" y="30">
        <parameter key="repository_entry" value="//Samples/data/Iris"/>
      </operator>
      <portSpacing port="source_input 1" spacing="0"/>
      <portSpacing port="sink_result 1" spacing="0"/>
    </process>
  </operator>
</process>

This line connects the operator referenced by its name to the first output port of the process:

process.getOperator("Retrieve").getOutputPorts().getPortByName("output").connectTo(process.getRootOperator().getSubprocess(0).getInnerSinks().getPortByIndex(0));

And in case you need a procedure for input ports as well, you can find it here.

Regards,
Marco

prayerslayer

Thanks a lot, works like a charm