package at.gv.egovernment.moa.spss.server.iaik.xml;

import java.util.Map;

import iaik.server.modules.xml.XPathTransformation;

/**
 * A <code>Transformation</code> containing an XPath expression.
 * 
 * @author Patrick Peck
 * @version $Id$
 */
public class XPathTransformationImpl
  extends TransformationImpl
  implements XPathTransformation {

  /** The XPath expression. */
  private String xPathExpression;
  /** The namespace prefix to URI mapping to use for XPath evaluation. */
  private Map namespaceDeclarations;

  /**
   * Create a new <code>XPathTransformationImpl</code>.
   * 
   * The namespace declarations are initialized empty.
   * 
   * @param xPathExpression The XPath expression this object will contain.
   * @param namespaceDeclarations The namespace declarations visible for this
   * XPath.
   */
  public XPathTransformationImpl(
    String xPathExpression,
    Map namespaceDeclarations) {

    setAlgorithmURI(XPathTransformation.XPATH);
    setXPathExpression(xPathExpression);
    setNamespaceDeclarations(namespaceDeclarations);
  }

  /**
   * Set the XPath expression.
   * 
   * @param xPathExpression The XPath expression.
   */
  protected void setXPathExpression(String xPathExpression) {
    this.xPathExpression = xPathExpression;
  }

  /**
   * @see iaik.server.modules.xml.XPathTransformation#getXPathExpression()
   */
  public String getXPathExpression() {
    return xPathExpression;
  }

  /**
   * @see iaik.server.modules.xml.XPathTransformation#getNamespaceDeclarations()
   */
  public Map getNamespaceDeclarations() {
    return namespaceDeclarations;
  }

  /**
   * Set the namespace declarations.
   * 
   * @param namespaceDeclarations The mapping between namespace prefixes and
   * their associated URI.
   */
  protected void setNamespaceDeclarations(Map namespaceDeclarations) {
    this.namespaceDeclarations = namespaceDeclarations;
  }

  /**
   * Compare this <code>XPathTransformation</code> to another.
   * 
   * @param other The object to compare this 
   * <code>XPathTransformation</code> to.
   * @return <code>true</code>, if <code>other</code> is an
   * <code>XPathTransformation</code> and if this object contains the same XPath
   * expression as <code>other</code>. Otherwise <code>false</code> is returned.
   * @see java.lang.Object#equals(Object)
   */
  public boolean equals(Object other) {
    if (other instanceof XPathTransformation) {
      XPathTransformation transform = (XPathTransformation) other;
      return getXPathExpression().equals(transform.getXPathExpression());
    }
    return false;
  }

  /**
   * @see java.lang.Object#hashCode()
   */
  public int hashCode() {
    return getXPathExpression().hashCode();
  }

}