samoa-api/src/main/java/org/apache/samoa/moa/options/ClassOption.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.samoa.moa.options;

import java.io.File;

import org.apache.samoa.moa.options.OptionHandler;
import org.apache.samoa.moa.tasks.Task;

import com.github.javacliparser.Option;
import com.github.javacliparser.Options;

/**
 * Class option.
 * 
 * @author Richard Kirkby (rkirkby@cs.waikato.ac.nz)
 * @version $Revision: 7 $
 */
public class ClassOption extends AbstractClassOption {

  private static final long serialVersionUID = 1L;

  public ClassOption(String name, char cliChar, String purpose,
      Class<?> requiredType, String defaultCLIString) {
    super(name, cliChar, purpose, requiredType, defaultCLIString);
  }

  public ClassOption(String name, char cliChar, String purpose,
      Class<?> requiredType, String defaultCLIString, String nullString) {
    super(name, cliChar, purpose, requiredType, defaultCLIString, nullString);
  }

  @Override
  public String getValueAsCLIString() {
    if ((this.currentValue == null) && (this.nullString != null)) {
      return this.nullString;
    }
    return objectToCLIString(this.currentValue, this.requiredType);
  }

  @Override
  public void setValueViaCLIString(String s) {
    if ((this.nullString != null)
        && ((s == null) || (s.length() == 0) || s.equals(this.nullString))) {
      this.currentValue = null;
    } else {
      try {
        this.currentValue = cliStringToObject(s, this.requiredType,
            null);
      } catch (Exception e) {
        throw new IllegalArgumentException("Problems with option: " + getName(), e);
      }
    }
  }

  public static String objectToCLIString(Object obj, Class<?> requiredType) {
    if (obj == null) {
      return "";
    }
    if (obj instanceof File) {
      return (FILE_PREFIX_STRING + ((File) obj).getPath());
    }
    if (obj instanceof String) {
      return (INMEM_PREFIX_STRING + obj);
    }
    String className = classToCLIString(obj.getClass(), requiredType);
    if (obj instanceof OptionHandler) {
      String subOptions = ((OptionHandler) obj).getOptions().getAsCLIString();
      if (subOptions.length() > 0) {
        return (className + " " + subOptions);
      }
    }
    return className;
  }

  public static Object cliStringToObject(String cliString,
      Class<?> requiredType, Option[] externalOptions) throws Exception {
    if (cliString.startsWith(FILE_PREFIX_STRING)) {
      return new File(cliString.substring(FILE_PREFIX_STRING.length()));
    }
    if (cliString.startsWith(INMEM_PREFIX_STRING)) {
      return cliString.substring(INMEM_PREFIX_STRING.length());
    }
    cliString = cliString.trim();
    int firstSpaceIndex = cliString.indexOf(' ', 0);
    String className;
    String classOptions;
    if (firstSpaceIndex > 0) {
      className = cliString.substring(0, firstSpaceIndex);
      classOptions = cliString.substring(firstSpaceIndex + 1, cliString.length());
      classOptions = classOptions.trim();
    } else {
      className = cliString;
      classOptions = "";
    }
    Class<?> classObject;
    try {
      classObject = Class.forName(className);
    } catch (Throwable t1) {
      try {
        // try prepending default package
        classObject = Class.forName(requiredType.getPackage().getName()
            + "." + className);
      } catch (Throwable t2) {
        try {
          // try prepending task package
          classObject = Class.forName(Task.class.getPackage().getName()
              + "." + className);
        } catch (Throwable t3) {
          throw new Exception("Class not found: " + className);
        }
      }
    }
    Object classInstance;
    try {
      classInstance = classObject.newInstance();
    } catch (Exception ex) {
      throw new Exception("Problem creating instance of class: "
          + className, ex);
    }
    if (requiredType.isInstance(classInstance)
        || ((classInstance instanceof Task) && requiredType
            .isAssignableFrom(((Task) classInstance).getTaskResultType()))) {
      Options options = new Options();
      if (externalOptions != null) {
        for (Option option : externalOptions) {
          options.addOption(option);
        }
      }
      if (classInstance instanceof OptionHandler) {
        Option[] objectOptions = ((OptionHandler) classInstance).getOptions().getOptionArray();
        for (Option option : objectOptions) {
          options.addOption(option);
        }
      }
      try {
        options.setViaCLIString(classOptions);
      } catch (Exception ex) {
        throw new Exception("Problem with options to '"
            + className
            + "'."
            + "\n\nValid options for "
            + className
            + ":\n"
            + ((OptionHandler) classInstance).getOptions().getHelpString(), ex);
      } finally {
        options.removeAllOptions(); // clean up listener refs
      }
    } else {
      throw new Exception("Class named '" + className
          + "' is not an instance of " + requiredType.getName() + ".");
    }
    return classInstance;
  }

  // @Override
  // public JComponent getEditComponent() {
  // return new ClassOptionEditComponent(this);
  // }
}