    001// Copyright 2008, 2011 The Apache Software Foundation
    002//
    003// Licensed under the Apache License, Version 2.0 (the "License");
    004// you may not use this file except in compliance with the License.
    005// You may obtain a copy of the License at
    006//
    007//     http://www.apache.org/licenses/LICENSE-2.0
    008//
    009// Unless required by applicable law or agreed to in writing, software
    010// distributed under the License is distributed on an "AS IS" BASIS,
    011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    012// See the License for the specific language governing permissions and
    013// limitations under the License.
    014
    015package org.apache.tapestry5.corelib.components;
    016
    017import org.apache.tapestry5.annotations.Parameter;
    018import org.apache.tapestry5.corelib.base.AbstractConditional;
    019
    020/**
    021 * A close relative of the {@link org.apache.tapestry5.corelib.components.If} component that inverts the meaning of its
    022 * test. This is easier than an {@link org.apache.tapestry5.corelib.components.If} component with the negate parameter set to {@code true}.
    023 *
    024 * @tapestrydoc
    025 */
    026public class Unless extends AbstractConditional
    027{
    028    /**
    029     * If true, then the body of the component is omitted. If false, the body is rendered.
    030     */
    031    @Parameter(required = true)
    032    private boolean test;
    033
    034    /**
    035     * @return test parameter inverted
    036     */
    037    protected boolean test()
    038    {
    039        return !test;
    040    }
    041}