core-server/src/main/java/org/glassfish/jersey/server/JSONP.java

/*
 * Copyright (c) 2012, 2018 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.jersey.server;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Annotation can be used to define the JavaScript callback function name if the valid JSONP format is requested as an
 * acceptable {@link javax.ws.rs.core.MediaType media type} of this request. At the moment only resource methods are supported to
 * be annotated with this annotation.
 * <p/>
 * The acceptable JavaScript media types for JSONP compatible with this annotation are:
 * <ul>
 * <li>application/x-javascript</li>
 * <li>application/javascript</li>
 * <li>application/ecmascript</li>
 * <li>text/javascript</li>
 * <li>text/x-javascript</li>
 * <li>text/ecmascript</li>
 * <li>text/jscript</li>
 * </ul>
 * <p/>
 * Note: Determining the JavaScript callback function name from a query parameter ({@link #queryParam}) takes precedence over
 * the {@link #callback()} value.
 *
 * @author Michal Gajdos
 */
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface JSONP {

    /**
     * Default JavaScript callback function name.
     */
    public static final String DEFAULT_CALLBACK = "callback";

    /**
     * Default query parameter name to obtain the JavaScript callback function name from.
     */
    public static final String DEFAULT_QUERY = "__callback";

    /**
     * Name of the JavaScript callback function to which the JSON result should be wrapped into.
     */
    String callback() default DEFAULT_CALLBACK;

    /**
     * If set then the JavaScript callback function name is obtained from a query parameter with the given name. If this query
     * parameter is not present in the request then the value of {@link #callback()} property is used as the JavaScript callback
     * function name.
     */
    String queryParam() default "";
}