org.springframework.security.config.annotation.AbstractSecurityBuilder Maven / Gradle / Ivy
/*
* Copyright 2002-2013 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.security.config.annotation;
import java.util.concurrent.atomic.AtomicBoolean;
/**
* A base {@link SecurityBuilder} that ensures the object being built is only built one
* time.
*
* @param the type of Object that is being built
*
* @author Rob Winch
*
*/
public abstract class AbstractSecurityBuilder implements SecurityBuilder {
private AtomicBoolean building = new AtomicBoolean();
private O object;
/*
* (non-Javadoc)
*
* @see org.springframework.security.config.annotation.SecurityBuilder#build()
*/
public final O build() throws Exception {
if (this.building.compareAndSet(false, true)) {
this.object = doBuild();
return this.object;
}
throw new AlreadyBuiltException("This object has already been built");
}
/**
* Gets the object that was built. If it has not been built yet an Exception is
* thrown.
*
* @return the Object that was built
*/
public final O getObject() {
if (!this.building.get()) {
throw new IllegalStateException("This object has not been built");
}
return this.object;
}
/**
* Subclasses should implement this to perform the build.
*
* @return the object that should be returned by {@link #build()}.
*
* @throws Exception if an error occurs
*/
protected abstract O doBuild() throws Exception;
}