org.springframework.jndi.JndiObjectLocator Maven / Gradle / Ivy
/*
* Copyright 2002-2005 the original author or authors.
*
* Licensed 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.springframework.jndi;
import javax.naming.NamingException;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.util.StringUtils;
/**
* Convenient superclass for JNDI-based service locators. Subclasses are
* JavaBeans, exposing a "jndiName" property. This may or may not include
* the "java:comp/env/" prefix expected by J2EE applications when accessing
* a locally mapped (ENC - Environmental Naming Context) resource. If it
* doesn't, the "java:comp/env/" prefix will be prepended if the "resourceRef"
* property is true (the default is false) and no other scheme
* like "java:" is given.
*
* Subclasses can invoke the lookup method whenever it is appropriate.
* Some classes might do this on initialization, while others might do it
* on demand. The latter strategy is more flexible in that it allows for
* initialization of the locator before the JNDI object is available.
*
* @author Juergen Hoeller
* @see #setJndiName
* @see #setJndiTemplate
* @see #setJndiEnvironment
* @see #setResourceRef
* @see #lookup()
*/
public abstract class JndiObjectLocator extends JndiLocatorSupport implements InitializingBean {
private String jndiName;
private Class expectedType;
/**
* Set the JNDI name to look up. If it doesn't begin with "java:comp/env/"
* this prefix is added if resourceRef is set to true.
* @param jndiName JNDI name to look up
* @see #setResourceRef
*/
public void setJndiName(String jndiName) {
this.jndiName = jndiName;
}
/**
* Return the JNDI name to look up.
*/
public String getJndiName() {
return jndiName;
}
/**
* Set the type that the located JNDI object is supposed
* to be assignable to, if any.
*/
public void setExpectedType(Class expectedType) {
this.expectedType = expectedType;
}
/**
* Return the type that the located JNDI object is supposed
* to be assignable to, if any.
*/
public Class getExpectedType() {
return expectedType;
}
/**
* Check the jndiName property and initiate a lookup.
*
The JNDI object will thus be fetched eagerly on initialization.
* For refreshing the JNDI object, subclasses can invoke lookup
* at any later time.
* @see #lookup
*/
public void afterPropertiesSet() throws NamingException {
if (!StringUtils.hasLength(getJndiName())) {
throw new IllegalArgumentException("jndiName is required");
}
}
/**
* Perform the actual JNDI lookup via the JndiTemplate.
* Invokes the located method after successful lookup.
* @throws NamingException if the JNDI lookup failed or if the
* located JNDI object is not assigable to the expected type
* @see #setJndiName
* @see #setExpectedType
*/
protected Object lookup() throws NamingException {
Object jndiObject = lookup(getJndiName());
// Check expected type, if any.
if (getExpectedType() != null && !getExpectedType().isInstance(jndiObject)) {
throw new NamingException(
"Located JNDI object [" + jndiObject + "] is not assignable to expected type [" +
this.expectedType.getName() + "]");
}
return jndiObject;
}
}