org.jboss.arquillian.graphene.spi.SecurityActions Maven / Gradle / Ivy
/**
* JBoss, Home of Professional Open Source
* Copyright 2013, Red Hat, Inc. and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.arquillian.graphene.spi;
import java.lang.reflect.Constructor;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
/**
* SecurityActions
*
* A set of privileged actions that are not to leak out of this package
*
*
* @author ALR
*
* @version $Revision: $
*/
final class SecurityActions {
// -------------------------------------------------------------------------------||
// Constructor
// ------------------------------------------------------------------||
// -------------------------------------------------------------------------------||
/**
* No instantiation
*/
private SecurityActions() {
throw new UnsupportedOperationException("No instantiation");
}
// -------------------------------------------------------------------------------||
// Utility Methods
// --------------------------------------------------------------||
// -------------------------------------------------------------------------------||
/**
* Obtains the Thread Context ClassLoader
*/
static ClassLoader getThreadContextClassLoader() {
return AccessController.doPrivileged(GetTcclAction.INSTANCE);
}
/**
* Obtains the Constructor specified from the given Class and argument types
*
* @param clazz
* @param argumentTypes
* @return
* @throws NoSuchMethodException
*/
static Constructor getConstructor(final Class clazz, final Class... argumentTypes) throws NoSuchMethodException {
try {
return AccessController.doPrivileged(new PrivilegedExceptionAction>() {
public Constructor run() throws NoSuchMethodException {
try {
return clazz.getConstructor(argumentTypes);
} catch (NoSuchMethodException e) {
Constructor declaredConstructor = clazz.getDeclaredConstructor(argumentTypes);
declaredConstructor.setAccessible(true);
return declaredConstructor;
}
}
});
}
// Unwrap
catch (final PrivilegedActionException pae) {
final Throwable t = pae.getCause();
// Rethrow
if (t instanceof NoSuchMethodException) {
throw (NoSuchMethodException) t;
} else {
// No other checked Exception thrown by Class.getConstructor
try {
throw (RuntimeException) t;
}
// Just in case we've really messed up
catch (final ClassCastException cce) {
throw new RuntimeException("Obtained unchecked Exception; this code should never be reached", t);
}
}
}
}
/**
* Create a new instance by finding a constructor that matches the argumentTypes signature using the arguments for
* instantiation.
*
* @param className Full classname of class to create
* @param argumentTypes The constructor argument types
* @param arguments The constructor arguments
* @return a new instance
* @throws IllegalArgumentException if className, argumentTypes, or arguments are null
* @throws RuntimeException if any exceptions during creation
* @author Aslak Knutsen
* @author ALR
*/
static T newInstance(final String className, final Class[] argumentTypes, final Object[] arguments,
final Class expectedType) {
if (className == null) {
throw new IllegalArgumentException("ClassName must be specified");
}
if (argumentTypes == null) {
throw new IllegalArgumentException("ArgumentTypes must be specified. Use empty array if no arguments");
}
if (arguments == null) {
throw new IllegalArgumentException("Arguments must be specified. Use empty array if no arguments");
}
final Object obj;
try {
final ClassLoader tccl = getThreadContextClassLoader();
final Class implClass = Class.forName(className, false, tccl);
Constructor constructor = getConstructor(implClass, argumentTypes);
obj = constructor.newInstance(arguments);
} catch (Exception e) {
throw new RuntimeException("Could not create new instance of " + className + ", missing package from classpath?", e);
}
// Cast
try {
return expectedType.cast(obj);
} catch (final ClassCastException cce) {
// Reconstruct so we get some useful information
throw new ClassCastException("Incorrect expected type, " + expectedType.getName() + ", defined for "
+ obj.getClass().getName());
}
}
// -------------------------------------------------------------------------------||
// Inner Classes
// ----------------------------------------------------------------||
// -------------------------------------------------------------------------------||
/**
* Single instance to get the TCCL
*/
private enum GetTcclAction implements PrivilegedAction {
INSTANCE;
public ClassLoader run() {
return Thread.currentThread().getContextClassLoader();
}
}
}