com.github.mjeanroy.spring.mappers.commons.ClassUtils Maven / Gradle / Ivy
/**
* The MIT License (MIT)
*
* Copyright (c) 2014
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.github.mjeanroy.spring.mappers.commons;
import org.springframework.core.type.AnnotationMetadata;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.Map;
/**
* Static class utilities.
*/
public final class ClassUtils {
private ClassUtils() {
}
/**
* Check that a given class is available on
* classpath.
*
* @param className Class name.
* @return True if class is available, false otherwise.
*/
public static boolean isPresent(String className) {
try {
Class.forName(className);
return true;
}
catch (Exception ex) {
return false;
}
}
/**
* Get annotation method value.
*
* @param importingClassMetadata Metadata.
* @param annotationClass Annotation class to look for.
* @param name Name of method.
* @param defaultValue Default value if original value is null.
* @param Type of returned value.
* @return Annotation value, or default value if original value is null.
*/
@SuppressWarnings("unchecked")
public static T getAnnotationValue(AnnotationMetadata importingClassMetadata, Class annotationClass, String name, T defaultValue) {
Map attributes = importingClassMetadata.getAnnotationAttributes(annotationClass.getName());
T value = (T) attributes.get(name);
if (value == null) {
value = defaultValue;
}
return value;
}
/**
* Get generic type of given class at specified index.
*
* @param clazz Class.
* @param index Index.
* @return Generic type.
*/
public static Class getGenericType(Class clazz, int index) {
Type generic = clazz.getGenericSuperclass();
if (generic == null) {
return null;
}
Class current = clazz;
while (!(generic instanceof ParameterizedType)) {
current = current.getSuperclass();
generic = current.getGenericSuperclass();
if (current.equals(Object.class)) {
return null;
}
}
return (Class) ((ParameterizedType) generic).getActualTypeArguments()[index];
}
}