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 * Copyright (c) 1999, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

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

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * 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

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package javax.naming;

/**

  * This class represents a name-to-object binding found in a context.

  *<p>

  * A context consists of name-to-object bindings.

  * The Binding class represents such a binding.  It consists

  * of a name and an object. The <code>Context.listBindings()</code>

  * method returns an enumeration of Binding.

  *<p>

  * Use subclassing for naming systems that generate contents of

  * a binding dynamically.

  *<p>

  * A Binding instance is not synchronized against concurrent access by multiple

  * threads. Threads that need to access a Binding concurrently should

  * synchronize amongst themselves and provide the necessary locking.

  *

  * @author Rosanna Lee

  * @author Scott Seligman

  * @since 1.3

  */

public class Binding extends NameClassPair {

    /**

     * Contains this binding's object.

     * <tt>setObject</tt>.

     * @serial

     * @see #getObject

     * @see #setObject

     */

    private Object boundObj;

    /**

      * Constructs an instance of a Binding given its name and object.

      *<p>

      * <tt>getClassName()</tt> will return

      * the class name of <tt>obj</tt> (or null if <tt>obj</tt> is null)

      * unless the class name has been explicitly set using <tt>setClassName()</tt>

      *

      * @param  name    The non-null name of the object. It is relative

      *             to the <em>target context</em> (which is

      * named by the first parameter of the <code>listBindings()</code> method)

      * @param  obj     The possibly null object bound to name.

      * @see NameClassPair#setClassName

      */

    public Binding(String name, Object obj) {

        super(name, null);

        this.boundObj = obj;

    }

    /**

      * Constructs an instance of a Binding given its name, object, and whether

      * the name is relative.

      *<p>

      * <tt>getClassName()</tt> will return the class name of <tt>obj</tt>

      * (or null if <tt>obj</tt> is null) unless the class name has been

      * explicitly set using <tt>setClassName()</tt>

      *

      * @param  name    The non-null string name of the object.

      * @param  obj     The possibly null object bound to name.

      * @param isRelative true if <code>name</code> is a name relative

      *         to the target context (which is named by

      *         the first parameter of the <code>listBindings()</code> method);

      *         false if <code>name</code> is a URL string.

      * @see NameClassPair#isRelative

      * @see NameClassPair#setRelative

      * @see NameClassPair#setClassName

      */

    public Binding(String name, Object obj, boolean isRelative) {

        super(name, null, isRelative);

        this.boundObj = obj;

    }

    /**

      * Constructs an instance of a Binding given its name, class name, and object.

      *

      * @param  name    The non-null name of the object. It is relative

      *             to the <em>target context</em> (which is

      * named by the first parameter of the <code>listBindings()</code> method)

      * @param  className       The possibly null class name of the object

      *         bound to <tt>name</tt>. If null, the class name of <tt>obj</tt> is

      *         returned by <tt>getClassName()</tt>. If <tt>obj</tt> is also

      *         null, <tt>getClassName()</tt> will return null.

      * @param  obj     The possibly null object bound to name.

      * @see NameClassPair#setClassName

      */

    public Binding(String name, String className, Object obj) {

        super(name, className);

        this.boundObj = obj;

    }

    /**

      * Constructs an instance of a Binding given its

      * name, class name, object, and whether the name is relative.

      *

      * @param  name    The non-null string name of the object.

      * @param  className       The possibly null class name of the object

      *         bound to <tt>name</tt>. If null, the class name of <tt>obj</tt> is

      *         returned by <tt>getClassName()</tt>. If <tt>obj</tt> is also

      *         null, <tt>getClassName()</tt> will return null.

      * @param  obj     The possibly null object bound to name.

      * @param isRelative true if <code>name</code> is a name relative

      *         to the target context (which is named by

      *         the first parameter of the <code>listBindings()</code> method);

      *         false if <code>name</code> is a URL string.

      * @see NameClassPair#isRelative

      * @see NameClassPair#setRelative

      * @see NameClassPair#setClassName

      */

    public Binding(String name, String className, Object obj, boolean isRelative) {

        super(name, className, isRelative);

        this.boundObj = obj;

    }

    /**

      * Retrieves the class name of the object bound to the name of this binding.

      * If the class name has been set explicitly, return it.

      * Otherwise, if this binding contains a non-null object,

      * that object's class name is used. Otherwise, null is returned.

      *

      * @return A possibly null string containing class name of object bound.

      */

    public String getClassName() {

        String cname = super.getClassName();

        if (cname != null) {

            return cname;

        }

        if (boundObj != null)

            return boundObj.getClass().getName();

        else

            return null;

    }

    /**

      * Retrieves the object bound to the name of this binding.

      *

      * @return The object bound; null if this binding does not contain an object.

      * @see #setObject

      */

    public Object getObject() {

        return boundObj;

    }

    /**

     * Sets the object associated with this binding.

     * @param obj The possibly null object to use.

     * @see #getObject

     */

    public void setObject(Object obj) {

        boundObj = obj;

    }

    /**

      * Generates the string representation of this binding.

      * The string representation consists of the string representation

      * of the name/class pair and the string representation of

      * this binding's object, separated by ':'.

      * The contents of this string is useful

      * for debugging and is not meant to be interpreted programmatically.

      *

      * @return The non-null string representation of this binding.

      */

    public String toString() {

        return super.toString() + ":" + getObject();

    }

    /**

     * Use serialVersionUID from JNDI 1.1.1 for interoperability

     */

    private static final long serialVersionUID = 8839217842691845890L;

};