Integration of RapidMiner in Java application

Question

I have a text classification process in RapidMiner. It reads the test data from specified excel ssheet and does the classification. I have also a small Java application which is just running this process. Now I want to make the file input part in my aplication, so that everytime I would be able to specify the excel file from my application (not from RapidMiner). Any hints?

This is the code:

import com.rapidminer.RapidMiner;
import com.rapidminer.Process;
import com.rapidminer.example.Attribute;
import com.rapidminer.example.Example;
import com.rapidminer.example.ExampleSet;
import com.rapidminer.operator.IOContainer;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.OperatorException;



import java.io.File;
import java.io.IOException;
import java.util.Iterator;
import com.rapidminer.operator.io.ExcelExampleSource; 
import com.rapidminer.tools.XMLException;


public class Classification {

    public static void main(String [] args) throws Exception{
         ExampleSet resultSet1 = null;
         IOContainer ioInput = null;
        IOContainer ioResult;
        try {
            RapidMiner.setExecutionMode(RapidMiner.ExecutionMode.COMMAND_LINE);
            RapidMiner.init();
            Process pr = new Process(new File("C:\\Users\\MP-TEST\\Desktop\\Rapid_Test\\Wieder_Model.rmp"));
            Operator op = pr.getOperator("Read Excel");
            op.setParameter(ExcelExampleSource.PARAMETER_EXCEL_FILE, "C:\\Users\\MP-TEST\\Desktop\\Rapid_Test\\HaendlerRatings_neu.xls");
            ioResult = pr.run(ioInput);
            if (ioResult.getElementAt(0) instanceof ExampleSet) {
                resultSet1 = (ExampleSet)ioResult.getElementAt(0);

                for (Example example : resultSet1) {
                    Iterator<Attribute> allAtts = example.getAttributes().allAttributes();
                    while(allAtts.hasNext()) {
                        Attribute a = allAtts.next();
                                if (a.isNumerical()) {
                                        double value = example.getValue(a);
                                        System.out.println(value);

                                } else {
                                        String value = example.getValueAsString(a);
                                        System.out.println(value);
                                }
                         }
                }
                    }
        } catch (IOException | XMLException | OperatorException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }




          }
}

This is the error:

Apr 09, 2013 9:06:05 AM com.rapidminer.Process run
INFO: Process C:\Users\MP-TEST\Desktop\Rapid_Test\Wieder_Model.rmp starts
com.rapidminer.operator.UserError: A value for the parameter 'excel_file' must be specified! 
    at com.rapidminer.operator.nio.model.ExcelResultSetConfiguration.makeDataResultSet(ExcelResultSetConfiguration.java:316)
    at com.rapidminer.operator.nio.model.AbstractDataResultSetReader.createExampleSet(AbstractDataResultSetReader.java:127)
    at com.rapidminer.operator.io.AbstractExampleSource.read(AbstractExampleSource.java:52)
    at com.rapidminer.operator.io.AbstractExampleSource.read(AbstractExampleSource.java:1)
    at com.rapidminer.operator.io.AbstractReader.doWork(AbstractReader.java:126)
    at com.rapidminer.operator.Operator.execute(Operator.java:855)
    at com.rapidminer.operator.execution.SimpleUnitExecutor.execute(SimpleUnitExecutor.java:51)
    at com.rapidminer.operator.ExecutionUnit.execute(ExecutionUnit.java:711)
    at com.rapidminer.operator.OperatorChain.doWork(OperatorChain.java:379)
    at com.rapidminer.operator.Operator.execute(Operator.java:855)
    at com.rapidminer.Process.run(Process.java:949)
    at com.rapidminer.Process.run(Process.java:873)
    at com.rapidminer.Process.run(Process.java:832)
    at com.rapidminer.Process.run(Process.java:827)
    at Classification.main(Classification.java:29)

Best regards

Armen

Answer 1

Works fine for me:

• Download Rapidminer (and unzip the file)
• Into "lib" directory, you need:
  1. rapidminer.jar
  2. launcher.jar
  3. All jar in "/lib/freehep" directory.
• Put libs 1, 2 and 3 in your classpath java project (libraries)
• Copy this code and run:

    import com.rapidminer.Process;
    import com.rapidminer.RapidMiner;
    import com.rapidminer.operator.Operator;
    import com.rapidminer.operator.OperatorException;
    import com.rapidminer.operator.io.ExcelExampleSource;
    import com.rapidminer.tools.XMLException;
    import java.io.File;
    import java.io.IOException;
    import java.lang.Object;

    public class ReadRapidminerProcess {
      public static void main(String[] args) {
        try {
          RapidMiner.setExecutionMode(RapidMiner.ExecutionMode.COMMAND_LINE);
          RapidMiner.init();

          Process process = new Process(new File("/your_path/your_file.rmp"));
          process.run();

        } catch (IOException | XMLException | OperatorException ex) {
          ex.printStackTrace();
        }
      }
    }

I hope to help you, I searched a lot before finding the answer.

Answer 2

I see two ways to do that.

The first one would be to change programatically the XML definition of your process. Rapidminer processes are specified by an XML file with .rmp extension. In the file you will find the definition of the operator you wish to change. This is an excerpt from a simple process specifiing the Read Excel operator:

<operator activated="true" class="read_excel" compatibility="5.3.005" expanded="true" height="60" name="Read Excel" width="90" x="313" y="75">
    <parameter key="excel_file" value="D:\file.xls"/>    <!-- HERE IS THE FILE PATH -->
    <parameter key="sheet_number" value="1"/>
    <parameter key="imported_cell_range" value="A1"/>
    <parameter key="encoding" value="SYSTEM"/>
    <parameter key="first_row_as_names" value="true"/>
    <list key="annotations"/>
    <parameter key="date_format" value=""/>
    <parameter key="time_zone" value="SYSTEM"/>
    <parameter key="locale" value="English (United States)"/>
    <list key="data_set_meta_data_information"/>
    <parameter key="read_not_matching_values_as_missings" value="true"/>
    <parameter key="datamanagement" value="double_array"/>
</operator>

I highlighted the part where the path to the excel file is. You can overwrite that in your application. Just be careful not to break the XML file.

---

The other way is to modify the operator after you load the process in your java application. You can get a reference to your operator by Process#getOperator(String name) or Process#getAllOperators(). I guess it should be of one of these classes:

com.rapidminer.operator.io.ExcelExampleSource
com.rapidminer.operator.nio.ExcelExampleSource

When you find the correct operator you modify the path by Operator#setParameter(String key, String Value).

This code works for me with RapidMiner 5.3: (the process is just a Read Excel operator and a Write CSV operator)

package sorapid;

import com.rapidminer.Process;
import com.rapidminer.RapidMiner;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.io.ExcelExampleSource;
import com.rapidminer.tools.XMLException;
import java.io.File;
import java.io.IOException;

public class SOrapid {

  public static void main(String[] args) {
    try {
      RapidMiner.setExecutionMode(RapidMiner.ExecutionMode.COMMAND_LINE);
      RapidMiner.init();

      Process process = new Process(new File("c:\\Users\\Matlab\\.RapidMiner5\\repositories\\Local Repository\\processes\\test.rmp"));
      Operator op = process.getOperator("Read Excel");
      op.setParameter(ExcelExampleSource.PARAMETER_EXCEL_FILE, "d:\\excel.xls");
      process.run();

    } catch (IOException | XMLException | OperatorException ex) {
      ex.printStackTrace();
    }
  }
}