home | career | drupal | java | mac | mysql | perl | scala | uml | unix

Groovy example source code file (GrabConfig.java)

This example Groovy source code file (GrabConfig.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, grabconfig, grabconfig, target, target

The Groovy GrabConfig.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.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Used to modify the grape configuration for grab requests.
 * <p/>
 * An example involving databases:
 * <pre>
 * {@code @Grab}('mysql:mysql-connector-java:5.1.6'),
 * {@code @GrabConfig}(systemClassLoader=true)
 * import groovy.sql.Sql
 *
 * def sql=Sql.newInstance("jdbc:mysql://localhost/test", "user", "password", "com.mysql.jdbc.Driver")
 * println sql.firstRow('SELECT * FROM INFORMATION_SCHEMA.COLUMNS')
 * </pre>
 * Another example involving XStream:
 * <pre>
 * {@code @Grapes}([
 *     {@code @Grab}('com.thoughtworks.xstream:xstream:1.3.1'),
 *     {@code @Grab}('xpp3:xpp3_min:1.1.4c'),
 *     {@code @GrabConfig}(systemClassLoader=true, initContextClassLoader=true)
 * ])
 * import com.thoughtworks.xstream.*
 *
 * class Staff {
 *     String firstname, lastname, position
 * }
 *
 * def xstream = new XStream()
 * def john1 = new Staff(firstname:'John',
 *                      lastname:'Connor',
 *                      position:'Resistance Leader')
 *
 * // write out to XML file
 * new File("john.xml").withOutputStream { out ->
 *     xstream.toXML(john1, out)
 * }
 *
 * // now read back in
 * def john2
 * new File("john.xml").withInputStream { ins ->
 *     john2 = xstream.fromXML(ins)
 * }
 *
 * println john2.dump()
 * </pre>
 * <p/>
 * Further information about customising grape behavior 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 GrabConfig {
    /**
     * Set to true if you want to use the system classloader when loading the grape.
     * This is normally only required when a core Java class needs to reference the grabbed
     * classes, e.g. for a database driver accessed using DriverManager.
     */
    boolean systemClassLoader() default false;

    /**
     * Set to true if you want the context classloader to be initialised to the classloader
     * of the current class or script. This is useful for libraries or frameworks that assume
     * that the context classloader has been set. But be careful when using this flag as your
     * script or class might behave differently when called directly (from the command line or
     * from an IDE) versus when called from within a container, e.g. a web container or a JEE container.
     */
    boolean initContextClassLoader() default false;
}

Other Groovy examples (source code examples)

Here is a short list of links related to this Groovy GrabConfig.java source code file:

new blog posts

 

Copyright 1998-2014 Alvin Alexander, alvinalexander.com
All Rights Reserved.