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A Speedment bundle that shades all dependencies into one jar. This is
useful when deploying an application on a server.
/**
*
* Copyright (c) 2006-2019, Speedment, Inc. All Rights Reserved.
*
* 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 com.speedment.runtime.config.util;
import java.lang.reflect.Array;
import static java.util.Objects.requireNonNull;
/**
* Utility class used to find the correct {@link Class} given a {@link String},
* or to convert a class to the corresponding {@code String}.
*
* @author Emil Forslund
* @since 3.1.10
*/
public final class ClassUtil {
/**
* Returns the full name of the specified type (including the array brackets
* if it is an array class).
*
* @param clazz class
* @return the absolute class name
*/
public static String classToString(Class clazz) {
requireNonNull(clazz, "Class is null.");
if (clazz.isArray()) {
final Class original = clazz.getComponentType();
return classToString(original) + "[]";
} else {
return clazz.getName();
}
}
/**
* Attempts to find the specified class using the default class loader. The
* class name may contain square brackets to indicate an array class. If the
* class can't be found, an {@link ClassNotFoundException} is thrown.
*
* @param className the full class name
* @return the class with that name
*
* @throws ClassNotFoundException if the class name could not be found
*/
public static Class classFromString(String className) throws ClassNotFoundException {
return classFromString(className, null);
}
/**
* Attempts to find the specified class using the specified
* {@code classLoader}. If the class loader is {@code null}, then the
* default class loader is used. The class name may contain square brackets
* to indicate an array class. If the class can't be found, an
* {@link ClassNotFoundException} is thrown.
*
* @param className the full class name
* @param classLoader the class loader to use (or {@code null})
* @return the class with that name
*
* @throws ClassNotFoundException if the class name could not be found
*/
public static Class classFromString(String className, ClassLoader classLoader) throws ClassNotFoundException {
String inner = className;
int dimensions = 0;
while (inner.endsWith("[]")) {
inner = inner.substring(0, inner.length() - 2);
dimensions++;
}
final Class innerClass;
switch (inner) {
case "byte": innerClass = byte.class; break;
case "short": innerClass = short.class; break;
case "int": innerClass = int.class; break;
case "long": innerClass = long.class; break;
case "float": innerClass = float.class; break;
case "double": innerClass = double.class; break;
case "boolean": innerClass = boolean.class; break;
case "char": innerClass = char.class; break;
default: if (classLoader == null) {
innerClass = Class.forName(inner);
} else {
innerClass = classLoader.loadClass(inner);
}
}
if (dimensions == 0) {
return innerClass;
} else {
return Array.newInstance(innerClass, dimensions).getClass();
}
}
/**
* Utility classes should not be instantiated.
*/
private ClassUtil() {}
}