    001    // Copyright 2006, 2007, 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
    015    package org.apache.tapestry5.corelib.components;
    016
    017    import org.apache.tapestry5.annotations.Parameter;
    018    import org.apache.tapestry5.corelib.base.AbstractConditional;
    019
    020    /**
    021     * Conditionally renders its body. May render its tag and any informal parameters.
    022     *
    023     * @tapestrydoc
    024     */
    025    public class If extends AbstractConditional
    026    {
    027        /**
    028         * If true, then the body of the If component is rendered. If false, the body is omitted.
    029         */
    030        @Parameter(required = true)
    031        private boolean test;
    032
    033        /**
    034         * Optional parameter to invert the test. If true, then the body is rendered when the test parameter is false (not
    035         * true).
    036         *
    037         * @see Unless
    038         * @deprecated Since 5.3 as property expressions support the '!' invert operator
    039         */
    040        @Parameter
    041        private boolean negate;
    042
    043        /**
    044         * @return test parameter (if negate is false), or test parameter inverted (if negate is true)
    045         */
    046        protected boolean test()
    047        {
    048            return test != negate;
    049        }
    050
    051    }