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/**
* Copyright (c) 2012-2014, jcabi.com
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met: 1) Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer. 2) Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution. 3) Neither the name of the jcabi.com nor
* the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
* NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.jcabi.aspects.aj;
import com.jcabi.aspects.Immutable;
import com.jcabi.aspects.UnitedThrow;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
/**
* Throw single exception out of method.
*
* @author Krzysztof Krason ([email protected])
* @version $Id$
* @since 0.13
*/
@Aspect
@Immutable
public final class SingleException {
/**
* Catch all exceptions and throw a single selected exception.
*
* Try NOT to change the signature of this method, in order to keep
* it backward compatible.
*
* @param point Joint point
* @return The result of call
* @throws Throwable If something goes wrong inside
* @checkstyle IllegalThrowsCheck (8 lines)
*/
@Around(
// @checkstyle StringLiteralsConcatenation (2 lines)
"execution(* * (..))"
+ " && @annotation(com.jcabi.aspects.UnitedThrow)"
)
@SuppressWarnings("PMD.AvoidCatchingThrowable")
public Object wrap(final ProceedingJoinPoint point) throws Throwable {
final Method method =
MethodSignature.class.cast(point.getSignature()).getMethod();
final UnitedThrow annot = method.getAnnotation(UnitedThrow.class);
final Class clz = this.clazz(method, annot);
try {
return point.proceed();
// @checkstyle IllegalCatch (1 line)
} catch (final Throwable ex) {
Throwable throwable = ex;
if (!clz.isAssignableFrom(ex.getClass())) {
if (this.exists(clz)) {
throwable = clz.getConstructor(Throwable.class)
.newInstance(ex);
} else {
throwable = clz.newInstance();
}
}
throw throwable;
}
}
/**
* Check if there is a constructor with single Throwable argument.
* @param clz Class to check.
* @return Whether constructor exists.
*/
private boolean exists(final Class clz) {
boolean found = false;
for (final Constructor ctr : clz.getConstructors()) {
if ((ctr.getParameterTypes().length == 1)
&& (ctr.getParameterTypes()[0] == Throwable.class)) {
found = true;
break;
}
}
return found;
}
/**
* Get required exception class.
* @param method Method declaring exception.
* @param annot UnitedThrow annotation.
* @return Class of exception.
*/
@SuppressWarnings("unchecked")
private Class clazz(final Method method,
final UnitedThrow annot) {
Class clz = annot.value();
if (clz == UnitedThrow.None.class) {
if (method.getExceptionTypes().length == 0) {
clz = IllegalStateException.class;
} else {
clz = (Class) method
.getExceptionTypes()[0];
}
}
return clz;
}
}