1 /*
2 * Copyright (c) 1999, 2005, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.jndi.cosnaming;
27
28 import javax.naming.*;
29 import javax.naming.spi.NamingManager;
30
31 import java.util.NoSuchElementException;
32 import java.util.Hashtable;
33
34 import org.omg.CosNaming.*;
35
36 /**
37 * Implements the JNDI NamingEnumeration interface for COS
38 * Naming. Gets hold of a list of bindings from the COS Naming Server
39 * and allows the client to iterate through them.
40 *
41 * @author Raj Krishnamurthy
42 * @author Rosanna Lee
43 */
44
45 final class CNBindingEnumeration
46 implements NamingEnumeration<javax.naming.Binding> {
47
48 private static final int DEFAULT_BATCHSIZE = 100;
49 private BindingListHolder _bindingList; // list of bindings
50 private BindingIterator _bindingIter; // iterator for getting list of bindings
51 private int counter; // pointer in _bindingList
52 private int batchsize = DEFAULT_BATCHSIZE; // how many to ask for each time
53 private CNCtx _ctx; // ctx to list
54 private Hashtable<?,?> _env; // environment for getObjectInstance
55 private boolean more = false; // iterator done?
56 private boolean isLookedUpCtx = false; // iterating on a context beneath this context ?
57
58 /**
59 * Creates a CNBindingEnumeration object.
60 * @param ctx Context to enumerate
61 */
62 CNBindingEnumeration(CNCtx ctx, boolean isLookedUpCtx, Hashtable<?,?> env) {
63 // Get batch size to use
64 String batch = (env != null ?
65 (String)env.get(javax.naming.Context.BATCHSIZE) : null);
66 if (batch != null) {
67 try {
68 batchsize = Integer.parseInt(batch);
69 } catch (NumberFormatException e) {
70 throw new IllegalArgumentException("Batch size not numeric: " + batch);
71 }
72 }
73 _ctx = ctx;
74 _ctx.incEnumCount();
75 this.isLookedUpCtx = isLookedUpCtx;
76 _env = env;
77 _bindingList = new BindingListHolder();
78 BindingIteratorHolder _bindingIterH = new BindingIteratorHolder();
79
80 // Perform listing and request that bindings be returned in _bindingIter
81 // Upon return,_bindingList returns a zero length list
82 _ctx._nc.list(0, _bindingList, _bindingIterH);
83
84 _bindingIter = _bindingIterH.value;
85
86 // Get first batch using _bindingIter
87 if (_bindingIter != null) {
88 more = _bindingIter.next_n(batchsize, _bindingList);
89 } else {
90 more = false;
91 }
92 counter = 0;
93 }
94
95 /**
96 * Returns the next binding in the list.
97 * @exception NamingException any naming exception.
98 */
99
100 public javax.naming.Binding next() throws NamingException {
101 if (more && counter >= _bindingList.value.length) {
102 getMore();
103 }
104 if (more && counter < _bindingList.value.length) {
105 org.omg.CosNaming.Binding bndg = _bindingList.value[counter];
106 counter++;
107 return mapBinding(bndg);
108 } else {
109 throw new NoSuchElementException();
110 }
111 }
112
113
114 /**
115 * Returns true or false depending on whether there are more bindings.
116 * @return boolean value
117 */
118
119 public boolean hasMore() throws NamingException {
120 // If there's more, check whether current bindingList has been exhausted,
121 // and if so, try to get more.
122 // If no more, just say so.
123 return more ? (counter < _bindingList.value.length || getMore()) : false;
124 }
125
126 /**
127 * Returns true or false depending on whether there are more bindings.
128 * Need to define this to satisfy the Enumeration api requirement.
129 * @return boolean value
130 */
131
132 public boolean hasMoreElements() {
133 try {
134 return hasMore();
135 } catch (NamingException e) {
136 return false;
137 }
138 }
139
140 /**
141 * Returns the next binding in the list.
142 * @exception NoSuchElementException Thrown when the end of the
143 * list is reached.
144 */
145
146 public javax.naming.Binding nextElement() {
147 try {
148 return next();
149 } catch (NamingException ne) {
150 throw new NoSuchElementException();
151 }
152 }
153
154 public void close() throws NamingException {
155 more = false;
156 if (_bindingIter != null) {
157 _bindingIter.destroy();
158 _bindingIter = null;
159 }
160 if (_ctx != null) {
161 _ctx.decEnumCount();
162
163 /**
164 * context was obtained by CNCtx, the user doesn't have a handle to
165 * it, close it as we are done enumerating through the context
166 */
167 if (isLookedUpCtx) {
168 _ctx.close();
169 }
170 _ctx = null;
171 }
172 }
173
174 protected void finalize() {
175 try {
176 close();
177 } catch (NamingException e) {
178 // ignore failures
179 }
180 }
181
182 /**
183 * Get the next batch using _bindingIter. Update the 'more' field.
184 */
185 private boolean getMore() throws NamingException {
186 try {
187 more = _bindingIter.next_n(batchsize, _bindingList);
188 counter = 0; // reset
189 } catch (Exception e) {
190 more = false;
191 NamingException ne = new NamingException(
192 "Problem getting binding list");
193 ne.setRootCause(e);
194 throw ne;
195 }
196 return more;
197 }
198
199 /**
200 * Constructs a JNDI Binding object from the COS Naming binding
201 * object.
202 * @exception NameNotFound No objects under the name.
203 * @exception CannotProceed Unable to obtain a continuation context
204 * @exception InvalidName Name not understood.
205 * @exception NamingException One of the above.
206 */
207
208 private javax.naming.Binding mapBinding(org.omg.CosNaming.Binding bndg)
209 throws NamingException {
210 java.lang.Object obj = _ctx.callResolve(bndg.binding_name);
211
212 Name cname = CNNameParser.cosNameToName(bndg.binding_name);
213
214 try {
215 obj = NamingManager.getObjectInstance(obj, cname, _ctx, _env);
216 } catch (NamingException e) {
217 throw e;
218 } catch (Exception e) {
219 NamingException ne = new NamingException(
220 "problem generating object using object factory");
221 ne.setRootCause(e);
222 throw ne;
223 }
224
225 // Use cname.toString() instead of bindingName because the name
226 // in the binding should be a composite name
227 String cnameStr = cname.toString();
228 javax.naming.Binding jbndg = new javax.naming.Binding(cnameStr, obj);
229
230 NameComponent[] comps = _ctx.makeFullName(bndg.binding_name);
231 String fullName = CNNameParser.cosNameToInsString(comps);
232 jbndg.setNameInNamespace(fullName);
233 return jbndg;
234 }
235 }