JndiTemplate.java
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.shiro.jndi;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Properties;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NameNotFoundException;
import javax.naming.NamingException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Helper class that simplifies JNDI operations. It provides methods to lookup and
* bind objects, and allows implementations of the {@link JndiCallback} interface
* to perform any operation they like with a JNDI naming context provided.
* <p/>
* <p>Note that this implementation is an almost exact copy of the Spring Framework's identically named class from
* their 2.5.4 distribution - we didn't want to re-invent the wheel, but not require a full dependency on the
* Spring framework, nor does Spring make available only its JNDI classes in a small jar, or we would have used that.
* Since Shiro is also Apache 2.0 licensed, all regular licenses and conditions and authors have remained in tact.
*
* @see JndiCallback
* @see #execute
*/
public class JndiTemplate {
private static final Logger log = LoggerFactory.getLogger(JndiTemplate.class);
private Properties environment;
/** Create a new JndiTemplate instance. */
public JndiTemplate() {
}
/**
* Create a new JndiTemplate instance, using the given environment.
*
* @param environment the Properties to initialize with
*/
public JndiTemplate(Properties environment) {
this.environment = environment;
}
/**
* Set the environment for the JNDI InitialContext.
*
* @param environment the Properties to initialize with
*/
public void setEnvironment(Properties environment) {
this.environment = environment;
}
/**
* Return the environment for the JNDI InitialContext, or <code>null</code> if none should be used.
*
* @return the environment for the JNDI InitialContext, or <code>null</code> if none should be used.
*/
public Properties getEnvironment() {
return this.environment;
}
/**
* Execute the given JNDI context callback implementation.
*
* @param contextCallback JndiCallback implementation
* @return a result object returned by the callback, or <code>null</code>
* @throws NamingException thrown by the callback implementation
* @see #createInitialContext
*/
public Object execute(JndiCallback contextCallback) throws NamingException {
Context ctx = createInitialContext();
try {
return contextCallback.doInContext(ctx);
}
finally {
try {
ctx.close();
} catch (NamingException ex) {
log.debug("Could not close JNDI InitialContext", ex);
}
}
}
/**
* Create a new JNDI initial context. Invoked by {@link #execute}.
* <p>The default implementation use this template's environment settings.
* Can be subclassed for custom contexts, e.g. for testing.
*
* @return the initial Context instance
* @throws NamingException in case of initialization errors
*/
@SuppressWarnings({"unchecked"})
protected Context createInitialContext() throws NamingException {
Properties env = getEnvironment();
Hashtable icEnv = null;
if (env != null) {
icEnv = new Hashtable(env.size());
for (Enumeration en = env.propertyNames(); en.hasMoreElements();) {
String key = (String) en.nextElement();
icEnv.put(key, env.getProperty(key));
}
}
return new InitialContext(icEnv);
}
/**
* Look up the object with the given name in the current JNDI context.
*
* @param name the JNDI name of the object
* @return object found (cannot be <code>null</code>; if a not so well-behaved
* JNDI implementations returns null, a NamingException gets thrown)
* @throws NamingException if there is no object with the given
* name bound to JNDI
*/
public Object lookup(final String name) throws NamingException {
log.debug("Looking up JNDI object with name '{}'", name);
return execute(new JndiCallback() {
public Object doInContext(Context ctx) throws NamingException {
Object located = ctx.lookup(name);
if (located == null) {
throw new NameNotFoundException(
"JNDI object with [" + name + "] not found: JNDI implementation returned null");
}
return located;
}
});
}
/**
* Look up the object with the given name in the current JNDI context.
*
* @param name the JNDI name of the object
* @param requiredType type the JNDI object must match. Can be an interface or
* superclass of the actual class, or <code>null</code> for any match. For example,
* if the value is <code>Object.class</code>, this method will succeed whatever
* the class of the returned instance.
* @return object found (cannot be <code>null</code>; if a not so well-behaved
* JNDI implementations returns null, a NamingException gets thrown)
* @throws NamingException if there is no object with the given
* name bound to JNDI
*/
public Object lookup(String name, Class requiredType) throws NamingException {
Object jndiObject = lookup(name);
if (requiredType != null && !requiredType.isInstance(jndiObject)) {
String msg = "Jndi object acquired under name '" + name + "' is of type [" +
jndiObject.getClass().getName() + "] and not assignable to the required type [" +
requiredType.getName() + "].";
throw new NamingException(msg);
}
return jndiObject;
}
/**
* Bind the given object to the current JNDI context, using the given name.
*
* @param name the JNDI name of the object
* @param object the object to bind
* @throws NamingException thrown by JNDI, mostly name already bound
*/
public void bind(final String name, final Object object) throws NamingException {
log.debug("Binding JNDI object with name '{}'", name);
execute(new JndiCallback() {
public Object doInContext(Context ctx) throws NamingException {
ctx.bind(name, object);
return null;
}
});
}
/**
* Rebind the given object to the current JNDI context, using the given name.
* Overwrites any existing binding.
*
* @param name the JNDI name of the object
* @param object the object to rebind
* @throws NamingException thrown by JNDI
*/
public void rebind(final String name, final Object object) throws NamingException {
log.debug("Rebinding JNDI object with name '{}'", name);
execute(new JndiCallback() {
public Object doInContext(Context ctx) throws NamingException {
ctx.rebind(name, object);
return null;
}
});
}
/**
* Remove the binding for the given name from the current JNDI context.
*
* @param name the JNDI name of the object
* @throws NamingException thrown by JNDI, mostly name not found
*/
public void unbind(final String name) throws NamingException {
log.debug("Unbinding JNDI object with name '{}'", name);
execute(new JndiCallback() {
public Object doInContext(Context ctx) throws NamingException {
ctx.unbind(name);
return null;
}
});
}
}