/*
* 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.core.parameters;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.core.LocalVariableTableParameterNameDiscoverer;
import org.springframework.core.ParameterNameDiscoverer;
import org.springframework.core.PrioritizedParameterNameDiscoverer;
import org.springframework.security.access.method.P;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
/**
* Spring Security's default {@link ParameterNameDiscoverer} which tries a
* number of {@link ParameterNameDiscoverer} depending on what is found on the
* classpath.
*
* <ul>
* <li>Will use an instance of {@link AnnotationParameterNameDiscoverer} with
* {@link P} as a valid annotation. If, Spring Data is on the classpath will
* also add Param annotation.</li>
* <li>If Spring 4 is on the classpath, then DefaultParameterNameDiscoverer is
* added. This attempts to use JDK 8 information first and falls back to
* {@link LocalVariableTableParameterNameDiscoverer}.</li>
* <li>If Spring 4 is not on the classpath, then
* {@link LocalVariableTableParameterNameDiscoverer} is added directly.</li>
* </ul>
*
* @see AnnotationParameterNameDiscoverer
*
* @author Rob Winch
* @since 3.2
*/
public class DefaultSecurityParameterNameDiscoverer extends
PrioritizedParameterNameDiscoverer {
private final Log logger = LogFactory.getLog(getClass());
private static final String DEFAULT_PARAMETER_NAME_DISCOVERER_CLASSNAME =
"org.springframework.core.DefaultParameterNameDiscoverer";
private static final boolean DEFAULT_PARAM_DISCOVERER_PRESENT =
ClassUtils.isPresent(DEFAULT_PARAMETER_NAME_DISCOVERER_CLASSNAME, DefaultSecurityParameterNameDiscoverer.class.getClassLoader());
private static final String DATA_PARAM_CLASSNAME = "org.springframework.data.repository.query.Param";
private static final boolean DATA_PARAM_PRESENT =
ClassUtils.isPresent(DATA_PARAM_CLASSNAME, DefaultSecurityParameterNameDiscoverer.class.getClassLoader());
/**
* Creates a new instance with only the default
* {@link ParameterNameDiscoverer} instances.
*/
public DefaultSecurityParameterNameDiscoverer() {
this(Collections.<ParameterNameDiscoverer>emptyList());
}
/**
* Creates a new instance that first tries the passed in {@link ParameterNameDiscoverer} instances.
* @param parameterNameDiscovers the {@link ParameterNameDiscoverer} before trying the defaults. Cannot be null.
*/
@SuppressWarnings("unchecked")
public DefaultSecurityParameterNameDiscoverer(List<? extends ParameterNameDiscoverer> parameterNameDiscovers) {
Assert.notNull(parameterNameDiscovers, "parameterNameDiscovers cannot be null");
for(ParameterNameDiscoverer discover : parameterNameDiscovers) {
addDiscoverer(discover);
}
Set<String> annotationClassesToUse = new HashSet<String>(2);
annotationClassesToUse.add(P.class.getName());
if(DATA_PARAM_PRESENT) {
annotationClassesToUse.add(DATA_PARAM_CLASSNAME);
}
addDiscoverer(new AnnotationParameterNameDiscoverer(annotationClassesToUse));
if (DEFAULT_PARAM_DISCOVERER_PRESENT) {
try {
Class<? extends ParameterNameDiscoverer> paramNameDiscoverClass = (Class<? extends ParameterNameDiscoverer>) ClassUtils
.forName(DEFAULT_PARAMETER_NAME_DISCOVERER_CLASSNAME,
getClass().getClassLoader());
addDiscoverer(paramNameDiscoverClass.newInstance());
} catch (Exception e) {
logger.warn(
"Could not use "
+ DEFAULT_PARAMETER_NAME_DISCOVERER_CLASSNAME
+ ". Falling back to LocalVariableTableParameterNameDiscoverer.", e);
addDiscoverer(new LocalVariableTableParameterNameDiscoverer());
}
} else {
addDiscoverer(new LocalVariableTableParameterNameDiscoverer());
}
}
}