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package javax.servlet.jsp.el;

/**
 * <p>This class is used to customize the way an ExpressionEvaluator resolves
 * variable references at evaluation time.  For example, instances of this class can
 * implement their own variable lookup mechanisms, or introduce the
 * notion of "implicit variables" which override any other variables.
 * An instance of this class should be passed when evaluating
 * an expression.</p>
 *
 * <p>An instance of this class includes the context against which resolution
 * will happen</p>
 *
 * @deprecated As of JSP 2.1, replaced by {@link javax.el.ELResolver}
 * @since JSP 2.0
 */
public interface VariableResolver
{
  //-------------------------------------
  /**
   * Resolves the specified variable.
   * Returns null if the variable is not found.
   * 
   * @param pName the name of the variable to resolve
   * @return the result of the variable resolution
   *
   * @throws ELException if a failure occurred while trying to resolve
   *     the given variable
   **/
  public Object resolveVariable (String pName)
    throws ELException;
					
  //-------------------------------------
}