argument.java

一个完整的XACML工程,学习XACML技术的好例子!

/*
* Copyright (c) 2000-2005, University of Salford
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package issrg.pba.rbac;

/**
 * This interface is the abstract argument to an Action. It knows its type and
 * its value. However, there is still some confusion about how the value should
 * be returned and this may be updated in later versions.
 *
 * <p>The Argument is deployed in IF-statements only.
 *
 * @author E Ball
 * @author D W Chadwick
 * @author A Otenko
 * @version 0.2
 */

public interface Argument {

  /**
   * This method gets the type of the argument.
   *
   * @return the string name of the argument type
   */
  public abstract String getType();

  /**
   * This method gets the string encoding of the value of the argument.
   * This may be needed for output purposes only.
   * It is suggested to better override <code>equals</code> method of
   * <code>java.lang.Object</code> to make comparisons more efficient.
   *
   * @return the string representation of the value; the encoding must
   *	correspond to that which would be used in XML
   */
  public abstract String getValue();
}