javaurlcontextfactory.java

Tomcat 4.1与WebServer集成组件的源代码包.

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 * The Apache Software License, Version 1.1
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 *       "This product includes software developed by the 
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package org.apache.naming.modules.java;

import java.util.Hashtable;
import javax.naming.Name;
import javax.naming.Context;
import javax.naming.NamingException;
import javax.naming.spi.ObjectFactory;
import javax.naming.spi.InitialContextFactory;
import org.apache.naming.modules.memory.MemoryNamingContext;
//import org.apache.naming.ContextBindings;

import org.apache.tomcat.util.res.StringManager;

/**
 * Context factory for the "java:" namespace.
 * <p>
 * <b>Important note</b> : This factory MUST be associated with the "java" URL
 * prefix, which can be done by either :
 * <ul>
 * <li>Adding a 
 * java.naming.factory.url.pkgs=org.apache.naming property to the JNDI properties file</li>
 * <li>Setting an environment variable named Context.URL_PKG_PREFIXES with 
 * its value including the org.apache.naming package name. 
 * More detail about this can be found in the JNDI documentation : 
 * {@link javax.naming.spi.NamingManager#getURLContext(java.lang.String, java.util.Hashtable)}.</li>
 * </ul>
 * 
 * @author Remy Maucherat
 */

public class javaURLContextFactory implements ObjectFactory, InitialContextFactory
{


    // ----------------------------------------------------------- Constructors


    // -------------------------------------------------------------- Constants


    public static final String MAIN = "initialContext";


    // ----------------------------------------------------- Instance Variables


    /**
     * Initial context.
     */
    protected static Context initialContext = null;


    // --------------------------------------------------------- Public Methods


    // -------------------------------------------------- ObjectFactory Methods


    /**
     * Crete a new Context's instance.
     */
    public Object getObjectInstance(Object obj, Name name, Context nameCtx,
                                    Hashtable environment)
        throws NamingException {
        if ((ContextBindings.isThreadBound()) || 
            (ContextBindings.isClassLoaderBound())) {
            return new SelectorContext(environment);
        } else {
            return null;
        }
    }


    /**
     * Get a new (writable) initial context.
     */
    public Context getInitialContext(Hashtable environment)
        throws NamingException {
        if (ContextBindings.isThreadBound() || 
            (ContextBindings.isClassLoaderBound())) {
            // Redirect the request to the bound initial context
            return new SelectorContext(environment, true);
        } else {
            // If the thread is not bound, return a shared writable context
            if (initialContext == null)
                initialContext = new MemoryNamingContext(environment);
            return initialContext;
        }
    }


}