com.google.gwt.gadgets.client.GadgetFeature.java Source code

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Here is the source code for com.google.gwt.gadgets.client.GadgetFeature.java

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/*
 * Copyright 2008 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.gwt.gadgets.client;

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

/**
 * This is a tag interface for API objects that provide access to optional
 * features within the Gadget container. A GadgetFeature must define a zero-arg
 * constructor with an arbitrary access modifier.
 */
public interface GadgetFeature {

    /**
     * Allows the Gadget manifest generator to automatically generate
     * <code>requires</code> elements. The generator will examine all types to
     * which the Gadget is assignable and collect the feature names that are
     * required.
     */
    @Documented
    @Target(ElementType.TYPE)
    public @interface FeatureName {
        /**
         * A value used to indicate that the feature is implicitly available in the
         * container and does not need a <code>requires</code> tag in the manifest.
         */
        String INTRINSIC = "__@INTRINSIC@__";

        /**
         * Additional <code>MayRequire</code> tags can be added to the Gadget
         * manifest here.
         *
         * @deprecated
         */
        @Deprecated
        MayRequire[] requirements() default {};

        /**
         * The names of the features required from the container. If the feature is
         * intrinsic to the container, use the {@link #INTRINSIC} value.
         */
        String[] value();
    }

    /**
     * This annotation allows additional <code>MayRequire</code> tags to be added
     * to the module specification. It can be added via
     * {@link Gadget.ModulePrefs#requirements()} or
     * {@link FeatureName#requirements()}.
     *
     * @deprecated
     */
    @Deprecated
    @Target(value = {})
    public @interface MayRequire {
        /*
         * NB: The Target annotation above means this annotation can't be applied to
         * any Java element, but is only usable as a value in an annotation
         * property.
         */

        String TYPE_BROWSER = "browser";
        String TYPE_PLATFORM = "platform";
        String TYPE_PLUGIN = "plugin";

        /**
         * Provides optional explanatory text for the requirement.
         */
        String info() default "";

        /**
         * Specifies the minimum version of the requirement.
         */
        String min_version() default "";

        /**
         * Specifies the type of requirement. One of the predefined
         * <code>TYPE_</code> fields can be used, or a container-specific type may
         * be specified.
         */
        String type();

        /**
         * The value for the requirement.
         */
        String value();
    }
}