/*
* Copyright 2014 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.gradle.internal.rules;
import com.google.common.collect.Lists;
import groovy.lang.Closure;
import java.util.Arrays;
import java.util.List;
public class ClosureBackedRuleAction<T> implements RuleAction<T> {
private final Closure closure;
private final Class<? super T> subjectType;
private List<Class<?>> inputTypes;
public ClosureBackedRuleAction(Class<T> subjectType, Closure<?> closure) {
this.subjectType = subjectType;
this.closure = closure;
this.inputTypes = parseInputTypes(closure);
}
public List<Class<?>> getInputTypes() {
return inputTypes;
}
public void execute(T subject, List<?> inputs) {
Closure copy = (Closure) closure.clone();
copy.setResolveStrategy(Closure.DELEGATE_FIRST);
copy.setDelegate(subject);
if (closure.getMaximumNumberOfParameters() == 0) {
copy.call();
} else {
Object[] argList = new Object[inputs.size() + 1];
argList[0] = subject;
int i = 1;
for (Object arg : inputs) {
argList[i++] = arg;
}
copy.call(argList);
}
}
private List<Class<?>> parseInputTypes(Closure<?> closure) {
Class<?>[] parameterTypes = closure.getParameterTypes();
List<Class<?>> inputTypes = Lists.newArrayList();
if (parameterTypes.length != 0) {
if (parameterTypes[0].isAssignableFrom(subjectType)) {
for (Class<?> parameterType : Arrays.asList(parameterTypes).subList(1, parameterTypes.length)) {
inputTypes.add(parameterType);
}
} else {
throw new RuleActionValidationException(String.format("First parameter of rule action closure must be of type '%s'.", subjectType.getSimpleName()));
}
}
return inputTypes;
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
ClosureBackedRuleAction that = (ClosureBackedRuleAction) o;
return closure.equals(that.closure)
&& subjectType.equals(that.subjectType);
}
@Override
public int hashCode() {
int result = closure.hashCode();
result = 31 * result + subjectType.hashCode();
return result;
}
}