org.ajoberstar.gradle.util.ObjectUtil Maven / Gradle / Ivy
/*
* Copyright 2012-2015 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.ajoberstar.gradle.util;
import java.util.concurrent.Callable;
import groovy.lang.Closure;
/**
* Utility class for general {@code Object} related operations.
* @since 0.1.0
*/
public final class ObjectUtil {
/**
* Cannot instantiate
* @throws AssertionError always
*/
private ObjectUtil() {
throw new AssertionError("Cannot instantiate this class");
}
/**
* Unpacks the given object by recursively
* calling the {@code call()} method if the
* object is a {@code Closure} or {@code Callable}.
* @param obj the object to unpack
* @return the unpacked value of the object
*/
@SuppressWarnings("rawtypes")
public static Object unpack(Object obj) {
Object value = obj;
while (value != null) {
if (value instanceof Closure) {
value = ((Closure) value).call();
} else if (value instanceof Callable) {
try {
value = ((Callable) value).call();
} catch (Exception e) {
throw new RuntimeException(e);
}
} else {
return value;
}
}
return value;
}
/**
* Unpacks the given object to its {@code String}
* value. Same behavior as the other {@code unpack}
* method ending with a call to {@code toString()}.
* @param obj the value to unpack
* @return the unpacked string value
* @see ObjectUtil#unpack(Object)
*/
public static String unpackString(Object obj) {
Object value = unpack(obj);
return value == null ? null : value.toString();
}
}