ExceptionHandlerFactory.java

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package javax.faces.context;

import javax.faces.FacesWrapper;

/**
 * <p class="changed_added_2_0"><strong class="changed_modified_2_3">ExceptionHandlerFactory</strong>
 * is a factory object that creates (if needed) and returns a new {@link
 * ExceptionHandler} instance.</p>
 *
 * <div class="changed_added_2_0">

 * <p>There must be one <code>ExceptionHandlerFactory</code> instance per web
 * application that is utilizing JavaServer Faces.  This instance can be
 * acquired, in a portable manner, by calling:</p>
 *
 * <pre><code>
 *   ExceptionHandlerFactory factory = (ExceptionHandlerFactory)
 *    FactoryFinder.getFactory(FactoryFinder.EXCEPTION_HANDLER_FACTORY);
 * </code></pre>
 *

 * </div>
 *
 * <p class="changed_added_2_3">Usage: extend this class and push the implementation being wrapped to the
 * constructor and use {@link #getWrapped} to access the instance being wrapped.</p>
 *
 * @since 2.0
 */

public abstract class ExceptionHandlerFactory implements FacesWrapper<ExceptionHandlerFactory> {

    private ExceptionHandlerFactory wrapped;

    /**
     * @deprecated Use the other constructor taking the implementation being wrapped.
     */
    @Deprecated
    public ExceptionHandlerFactory() {

    }

    /**
     * <p class="changed_added_2_3">If this factory has been decorated,
     * the implementation doing the decorating should push the implementation being wrapped to this constructor.
     * The {@link #getWrapped()} will then return the implementation being wrapped.</p>
     *
     * @param wrapped The implementation being wrapped.
     */
    public ExceptionHandlerFactory(ExceptionHandlerFactory wrapped) {
        this.wrapped = wrapped;
    }

    /**
     * <p class="changed_modified_2_3">If this factory has been decorated, the
     * implementation doing the decorating may override this method to provide
     * access to the implementation being wrapped.</p>
     */
    @Override
    public ExceptionHandlerFactory getWrapped() {
        return wrapped;
    }

    /**
     * <p class="changed_added_2_0">Create and return a A new
     * <code>ExceptionHandler</code> instance.  The implementation must return
     * an <code>ExceptionHandler</code> instance suitable for the environment.
     * For example, in some cases it may be desirable for an
     * <code>ExceptionHandler</code> to write error information
     * to the response instead of throwing exceptions as in the case of
     * Ajax applications.</p>
     *
     *  @return newly created <code>ExceptionHandler</code>.
     *
     */
    public abstract ExceptionHandler getExceptionHandler();

}