Java tutorial
/* * Copyright (c) 1999, 2013, 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 * or visit www.oracle.com if you need additional information or have any * questions. */ 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. * It is initialized by the constructor and can be updated using * {@code setObject}. * @serial * @see #getObject * @see #setObject */ private Object boundObj; /** * Constructs an instance of a Binding given its name and object. *<p> * {@code getClassName()} will return * the class name of {@code obj} (or null if {@code obj} is null) * unless the class name has been explicitly set using {@code setClassName()} * * @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> * {@code getClassName()} will return the class name of {@code obj} * (or null if {@code obj} is null) unless the class name has been * explicitly set using {@code setClassName()} * * @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 {@code name}. If null, the class name of {@code obj} is * returned by {@code getClassName()}. If {@code obj} is also * null, {@code getClassName()} 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 {@code name}. If null, the class name of {@code obj} is * returned by {@code getClassName()}. If {@code obj} is also * null, {@code getClassName()} 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; };