Groovy example source code file (Grab.java)

This example Groovy source code file (Grab.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

annotation, grab, grab, string, string, target, target

The Groovy Grab.java source code

/*
 * Copyright 2003-2011 the original author or authors.
 *
 * 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 groovy.lang;

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

/**
 * Used to grab the referenced artifact and its dependencies and make it available on the Classpath.
 * <p/>
 * Some examples:
 * <pre>
 * {@code @Grab}(group='commons-lang', module='commons-lang', version='2.4')
 * import org.apache.commons.lang.WordUtils
 * println "Hello ${WordUtils.capitalize('world')}"
 * </pre>
 * Or using the compact Gradle-inspired syntax:
 * <pre>
 * {@code @Grab}('commons-lang:commons-lang:2.4')
 * import org.apache.commons.lang.WordUtils
 * println "Hello ${WordUtils.capitalize('world')}"
 * </pre>
 * or the same thing again using the Ivy-inspired syntax variant:
 * <pre>
 * {@code @Grab}('commons-lang#commons-lang;2.4')
 * import org.apache.commons.lang.WordUtils
 * println "Hello ${WordUtils.capitalize('world')}"
 * </pre>
 * Further information such as where artifacts are downloaded to, how to add additional resolvers,
 * how to customise artifact resolution etc., can be found on the Grape documentation page:
 * <a href="http://groovy.codehaus.org/Grape">http://groovy.codehaus.org/Grape.
 */
@Retention(RetentionPolicy.SOURCE)
@Target({
        ElementType.CONSTRUCTOR,
        ElementType.FIELD,
        ElementType.LOCAL_VARIABLE,
        ElementType.METHOD,
        ElementType.PARAMETER,
        ElementType.TYPE})
public @interface Grab {
    /**
     * The organisation or group, e.g.: "org.apache.ant"
     */
    String group() default "";

    /**
     * The module or artifact, e.g.: "ant-junit"
     */
    String module();

    /**
     * The revision or version, e.g.: "1.7.1"
     */
    String version();

    /**
     * The classifier if in use, e.g.: "jdk14"
     */
    String classifier() default "";

    /**
     * Defaults to {@code true} but set to {@code false} if you don't want transitive dependencies also to be downloaded.
     * You may then need additional {@code @Grab} statements for any required dependencies.
     */
    boolean transitive() default true;

    /**
     * Defaults to {@code false} but set to {@code true} to indicate to the underlying Ivy conflict manager that this
     * dependency should be forced to the given revision. Otherwise, depending on the conflict manager in play, a later
     * compatible version might be used instead.
     */
    boolean force() default false;

    /**
     * Defaults to {@code false} but set to {@code true} if the dependency artifacts may change without a corresponding
     * revision change. Not normally recommended but may be useful for certain kinds of snapshot artifacts.
     * May reduce the amount of underlying Ivy caching. Proper behavior may be dependent on the resolver in use.
     */
    boolean changing() default false;

    /**
     * The configuration if in use (normally only used by internal ivy repositories).
     * One or more comma separated values with or without square brackets,
     * e.g. for hibernate you might have "default,proxool,oscache" or "[default,dbcp,swarmcache]".
     * This last hibernate example assumes you have set up such configurations in your local Ivy repo
     * and have changed your grape config (using grapeConfig.xml) or the {@code @GrabConfig} annotation
     * to point to that repo.
     */
    String conf() default "";

    /**
     * The extension of the artifact (normally safe to leave at default value of "jar" but other values like "zip"
     * are sometimes useful).
     */
    String ext() default "";

    /**
     * The type of the artifact (normally safe to leave at default value of "jar" but other values like "sources" and "javadoc" are sometimes useful).
     * But see also the "classifier" attribute which is also sometimes used for "sources" and "javadoc".
     */
    String type() default "";

    /**
     * Allows a more compact convenience form in one of two formats with optional appended attributes.
     * <p/>
     * You can choose either format but not mix-n-match:<br/>
     * {@code group:module:version:classifier@ext} (where only group and module are required)<br/>
     * {@code group#module;version[confs]} (where only group and module are required and confs,
     * if used, is one or more comma separated configuration names)<br/>
     * In addition, you can add any valid Ivy attributes at the end of your string value using
     * semi-colon separated name = value pairs, e.g.:<br/>
     * {@code @Grab('junit:junit:*;transitive=false')}<br/>
     * {@code @Grab('group=junit;module=junit;version=4.8.2;classifier=javadoc')
}<br/>
     */
    String value() default "";

    /**
     * By default, when a {@code @Grab} annotation is used, the {@code grab()} call is added
     * to the static initializers of the class the annotatable node appears in.
     * If you wish to disable this, add {@code initClass=false} to the annotation.
     */
    boolean initClass() default true;
}