com.asual.summer.core.util.ClassUtils.java Source code

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Here is the source code for com.asual.summer.core.util.ClassUtils.java

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/*
 * 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.asual.summer.core.util;

import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;

import javax.inject.Named;

import org.springframework.util.ReflectionUtils;

/**
 * 
 * @author Rostislav Hristov
 *
 */
@Named
public class ClassUtils {

    public static Class<?> getClass(String clazz) throws ClassNotFoundException {
        return Class.forName(clazz);
    }

    public static Object cast(Object obj, String clazz) throws ClassNotFoundException {
        return Class.forName(clazz).cast(obj);
    }

    public static boolean isInstance(Object obj, String clazz) {
        try {
            return Class.forName(clazz).isInstance(obj);
        } catch (ClassNotFoundException e) {
            return false;
        }
    }

    public static Object newInstance(String clazz, Object... parameters)
            throws SecurityException, ClassNotFoundException {
        Class<?>[] classParameters = new Class[parameters == null ? 0 : parameters.length];
        for (int i = 0; i < classParameters.length; i++) {
            classParameters[i] = parameters[i].getClass();
        }
        Object instance = null;
        try {
            instance = Class.forName(clazz).getConstructor(classParameters)
                    .newInstance(parameters == null ? new Object[] {} : parameters.length);
        } catch (Exception e) {
            Constructor<?>[] constructors = Class.forName(clazz).getConstructors();
            for (Constructor<?> constructor : constructors) {
                Class<?>[] types = constructor.getParameterTypes();
                if (types.length == parameters.length) {
                    Object[] params = new Object[parameters.length];
                    for (int i = 0; i < parameters.length; i++) {
                        if (types[i] == boolean.class || types[i] == Boolean.class) {
                            params[i] = Boolean.valueOf(parameters[i].toString());
                        } else if (types[i] == int.class || types[i] == Integer.class) {
                            params[i] = Integer.valueOf(parameters[i].toString());
                        } else {
                            params[i] = types[i].cast(parameters[i]);
                        }
                    }
                    try {
                        instance = constructor.newInstance(params);
                        break;
                    } catch (Exception ex) {
                        continue;
                    }
                }
            }
        }
        return instance;
    }

    public static Object invokeMethod(Object target, final String methodName, final Object[] parameters) {
        if (target != null) {
            final List<Method> matches = new ArrayList<Method>();
            ReflectionUtils.doWithMethods(target.getClass(), new ReflectionUtils.MethodCallback() {
                public void doWith(Method method) throws IllegalArgumentException, IllegalAccessException {
                    matches.add(method);
                }
            }, new ReflectionUtils.MethodFilter() {
                public boolean matches(Method method) {
                    if (method.getName().equals(methodName)) {
                        Class<?>[] types = method.getParameterTypes();
                        if (parameters == null && types.length == 0) {
                            return true;
                        }
                        if (types.length != parameters.length) {
                            return false;
                        }
                        for (int i = 0; i < types.length; i++) {
                            if (!types[i].isInstance(parameters[i])) {
                                return false;
                            }
                        }
                        return true;
                    }
                    return false;
                }
            });
            if (matches.size() > 0) {
                if (parameters == null) {
                    return ReflectionUtils.invokeMethod(matches.get(0), target);
                } else {
                    return ReflectionUtils.invokeMethod(matches.get(0), target, parameters);
                }
            }
        }
        return null;
    }

}