/*
* Copyright 2002-2010 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,
* providing configurable lookup of a specific JNDI resource.
*
* <p>Exposes a {@link #setJndiName "jndiName"} property. This may or may not
* include the "java:comp/env/" prefix expected by J2EE applications when
* accessing a locally mapped (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 <strong>false</strong>) and no other scheme
* (e.g. "java:") is given.
*
* <p>Subclasses may invoke the {@link #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
* @since 1.1
* @see #setJndiName
* @see #setJndiTemplate
* @see #setJndiEnvironment
* @see #setResourceRef
* @see #lookup()
*/
public abstract class JndiObjectLocator extends JndiLocatorSupport implements InitializingBean {
private String jndiName;
private Class<?> expectedType;
/**
* Specify the JNDI name to look up. If it doesn't begin with "java:comp/env/"
* this prefix is added automatically if "resourceRef" is set to "true".
* @param jndiName the 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 this.jndiName;
}
/**
* Specify 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 this.expectedType;
}
public void afterPropertiesSet() throws IllegalArgumentException, NamingException {
if (!StringUtils.hasLength(getJndiName())) {
throw new IllegalArgumentException("Property 'jndiName' is required");
}
}
/**
* Perform the actual JNDI lookup for this locator's target resource.
* @return the located target object
* @throws NamingException if the JNDI lookup failed or if the
* located JNDI object is not assigable to the expected type
* @see #setJndiName
* @see #setExpectedType
* @see #lookup(String, Class)
*/
protected Object lookup() throws NamingException {
return lookup(getJndiName(), getExpectedType());
}
}
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