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 * published by the Free Software Foundation.  Oracle designates this

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 * This code is distributed in the hope that it will be useful, but WITHOUT

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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

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package com.sun.tools.internal.xjc.runtime;

import java.util.ArrayList;

import java.util.List;

import java.util.Map;

import java.util.StringTokenizer;

import javax.xml.bind.JAXBContext;

import javax.xml.bind.JAXBException;

/**

 * This class implements the actual logic of {@link JAXBContext#newInstance}.

 *

 * <p>

 * This class works as a facade and all the actual work is delegated to

 * a JAXB provider that happens to be in the runtime (not necessarily the JAXB RI.)

 * This allows the generated code to be run with any JAXB provider.

 *

 * <p>

 * This code is only used when XJC generates interfaces/implementations.

 *

 * <p>

 * The trick to make this work is two ObjectFactory classes that we generate

 * in the interface/implementation mode.

 *

 * <p>

 * The public ObjectFactory follows the spec, and this is the one that's exposed

 * to users. The public ObjectFactory refers to interfaces, so they aren't

 * directly usable by a JAXB 2.0 implementation.

 *

 * <p>

 * The private one lives in the impl package, and this one is indistinguishable

 * from the ObjectFactory that we generate for the value class generation mode.

 * This private ObjectFactory refers to implementation classes, which are

 * also indistinguishable from value classes that JAXB generates.

 *

 * <p>

 * All in all, the private ObjectFactory plus implementation classes give

 * a JAXB provider an illusion that they are dealing with value classes

 * that happens to implement some interfaces.

 *

 * <p>

 * In this way, the JAXB RI can provide the portability even for the

 * interface/implementation generation mode.

 *

 * @since 2.0

 * @author Kohsuke Kawaguchi

 */

public class JAXBContextFactory {

    private static final String DOT_OBJECT_FACTORY = ".ObjectFactory";

    private static final String IMPL_DOT_OBJECT_FACTORY = ".impl.ObjectFactory";

    /**

     * The JAXB API will invoke this method via reflection

     */

    public static JAXBContext createContext( Class[] classes, Map properties ) throws JAXBException {

        Class[] r = new Class[classes.length];

        boolean modified = false;

        // find any reference to our 'public' ObjectFactory and

        // replace that to our 'private' ObjectFactory.

        for( int i=0; i<r.length; i++ ) {

            Class c = classes[i];

            String name = c.getName();

            if(name.endsWith(DOT_OBJECT_FACTORY)

            && !name.endsWith(IMPL_DOT_OBJECT_FACTORY)) {

                // we never generate into the root package, so no need to worry about FQCN "ObjectFactory"

                // if we find one, tell the real JAXB provider to

                // load foo.bar.impl.ObjectFactory

                name = name.substring(0,name.length()-DOT_OBJECT_FACTORY.length())+IMPL_DOT_OBJECT_FACTORY;

                try {

                    c = getClassClassLoader(c).loadClass(name);

                } catch (ClassNotFoundException e) {

                    throw new JAXBException(e);

                }

                modified = true;

            }

            r[i] = c;

        }

        if(!modified) {

            // if the class list doesn't contain any of our classes,

            // this ContextFactory shouldn't have been called in the first place

            // if we simply continue, we'll just end up with the infinite recursion.

            // the only case that I can think of where this could happen is

            // when the user puts additional classes into the JAXB-generated

            // package and pass them to JAXBContext.newInstance().

            // Under normal use, this shouldn't happen.

            // anyway, bail out now.

            // if you hit this problem and wondering how to get around the problem,

            // subscribe and send a note to users@jaxb.dev.java.net (http://jaxb.dev.java.net/)

            throw new JAXBException("Unable to find a JAXB implementation to delegate");

        }

        // delegate to the JAXB provider in the system

        return JAXBContext.newInstance(r,properties);

    }

    /**

     * The JAXB API will invoke this method via reflection

     */

    public static JAXBContext createContext( String contextPath,

                                             ClassLoader classLoader, Map properties ) throws JAXBException {

        List<Class> classes = new ArrayList<Class>();

        StringTokenizer tokens = new StringTokenizer(contextPath,":");

        // each package should be pointing to a JAXB RI generated

        // content interface package.

        //

        // translate them into a list of private ObjectFactories.

        try {

            while(tokens.hasMoreTokens()) {

                String pkg = tokens.nextToken();

                classes.add(classLoader.loadClass(pkg+IMPL_DOT_OBJECT_FACTORY));

            }

        } catch (ClassNotFoundException e) {

            throw new JAXBException(e);

        }

        // delegate to the JAXB provider in the system

        return JAXBContext.newInstance(classes.toArray(new Class[classes.size()]),properties);

    }

    private static ClassLoader getClassClassLoader(final Class c) {

        if (System.getSecurityManager() == null) {

            return c.getClassLoader();

        } else {

            return (ClassLoader) java.security.AccessController.doPrivileged(

                    new java.security.PrivilegedAction() {

                        public java.lang.Object run() {

                            return c.getClassLoader();

                        }

                    });

        }

    }

}