AnswerChecker.java

package org.aitools.programd.test.aiml;

import java.io.UnsupportedEncodingException;

import org.aitools.util.Text;
import org.aitools.util.runtime.DeveloperError;
import org.aitools.util.xml.Characters;
import org.aitools.util.xml.XHTML;
import org.jdom.Element;
import org.jdom.output.Format;
import org.jdom.output.XMLOutputter;

/**
 * Tests whether a given input equals an expected string.
 * 
 * @author Albertas Mickensas
 * @author <a href="noel@aitools.org">Noel Bush</a>
 */
public class AnswerChecker extends Checker {

  private String expectedAnswer = null;

  /** A formatter used for outputting XML. */
  private Format _xmlFormat = Format.getPrettyFormat();

  /**
   * Creates a new AnswerChecker with the given expected answer.
   * 
   * @param element the element containing the expected answer
   * @param encoding the encoding of the document from which the element comes
   */
  public AnswerChecker(Element element, String encoding) {
    try {
      this.expectedAnswer = new String(Text.renderAsLines(
          XHTML.breakLines(Characters.unescapeXMLChars(new XMLOutputter(this._xmlFormat).outputString(element
              .getContent())))).getBytes(encoding)).intern();
    }
    catch (UnsupportedEncodingException e) {
      throw new DeveloperError(String.format("Platform does not support encoding \"%s\"!", encoding), e);
    }
  }

  /**
   * Creates a new AnswerChecked with the given expected answer.
   * 
   * @param answer the expected answer
   */
  public AnswerChecker(String answer) {
    this.expectedAnswer = answer;
  }

  /**
   * @see org.aitools.programd.test.aiml.Checker#getContent()
   */
  @Override
  public String getContent() {
    return this.expectedAnswer;
  }

  /**
   * @see org.aitools.programd.test.aiml.Checker#getExpected()
   */
  @Override
  public String getExpected() {
    return "Exact answer: " + this.expectedAnswer;
  }

  /**
   * @see org.aitools.programd.test.aiml.Checker#getTagName()
   */
  @Override
  public String getTagName() {
    return Checker.TAG_EXPECTED_ANSWER;
  }

  /**
   * Tests whether the given input matches the expected answer.
   * 
   * @param input the input to test
   * @return whether the given input matches the expected answer
   * @see org.aitools.programd.test.aiml.Checker#test(java.lang.String)
   */
  @Override
  public boolean test(String input) {
    if (null != this.expectedAnswer) {
      if (input.equals(this.expectedAnswer)) {
        return true;
      }
      // otherwise...
      return false;
    }
    // otherwise...
    return false;
  }
}