com.feilong.commons.core.lang.ClassUtil.java Source code

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Here is the source code for com.feilong.commons.core.lang.ClassUtil.java

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/*
 * Copyright (C) 2008 feilong (venusdrogon@163.com)
 *
 * 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.feilong.commons.core.lang;

import java.lang.reflect.Modifier;
import java.util.LinkedHashMap;
import java.util.Map;

/**
 * {@link java.lang.Class} .
 * 
 * @author <a href="mailto:venusdrogon@163.com"></a>
 * @version 1.0 2012-6-1 ?7:19:47
 * @since 1.0.0
 */
public final class ClassUtil {

    /** Don't let anyone instantiate this class. */
    private ClassUtil() {
        //AssertionError?. ?????. ???.
        //see Effective Java 2nd
        throw new AssertionError("No " + getClass().getName() + " instances for you!");
    }

    /**
     *  class info map for log.
     *
     * @param klass
     *            the clz
     * @return the map for log
     */
    public static Map<String, Object> getClassInfoMapForLog(Class<?> klass) {

        Map<String, Object> map = new LinkedHashMap<String, Object>();

        //"clz.getCanonicalName()": "com.feilong.commons.core.date.DatePattern",
        //"clz.getName()": "com.feilong.commons.core.date.DatePattern",
        //"clz.getSimpleName()": "DatePattern",

        // getCanonicalName ( Java Language Specification ??) && getName
        //??class?array?
        // getName[[Ljava.lang.String?getCanonicalName?
        map.put("clz.getCanonicalName()", klass.getCanonicalName());
        map.put("clz.getName()", klass.getName());
        map.put("clz.getSimpleName()", klass.getSimpleName());

        map.put("clz.getComponentType()", klass.getComponentType());
        // ?? voidboolean?byte?char?short?int?long?float  double?
        map.put("clz.isPrimitive()", klass.isPrimitive());

        // ??,
        map.put("clz.isLocalClass()", klass.isLocalClass());
        // ????,??????
        map.put("clz.isMemberClass()", klass.isMemberClass());

        //isSynthetic()?Class????java??false?trueJVM???java??????
        map.put("clz.isSynthetic()", klass.isSynthetic());
        map.put("clz.isArray()", klass.isArray());
        map.put("clz.isAnnotation()", klass.isAnnotation());

        //??true
        map.put("clz.isAnonymousClass()", klass.isAnonymousClass());
        map.put("clz.isEnum()", klass.isEnum());

        return map;
        //      Class<?> klass = this.getClass();
        //
        //      TypeVariable<?>[] typeParameters = klass.getTypeParameters();
        //      TypeVariable<?> typeVariable = typeParameters[0];
        //
        //      Type[] bounds = typeVariable.getBounds();
        //
        //      Type bound = bounds[0];
        //
        //      if (log.isDebugEnabled()){
        //         log.debug("" + (bound instanceof ParameterizedType));
        //      }
        //
        //      Class<T> modelClass = ReflectUtil.getGenericModelClass(klass);
        //      return modelClass;
    }

    /**
     * .
     * 
     * <ol>
     * <li>Class cl=o.getClass();<br>
     * o?(:????)OClass.<br>
     * ?O??.</li>
     * <li>Class cl=A.class;<br>
     * JVMA,A(???:A),?A??.<br>
     * AClass.</li>
     * <li>Class cl=Class.forName("??");<br>
     * ?.</li>
     * <li>Class cl=ClassLoader.loadClass("??");<br>
     * ???.</li>
     * </ol>
     * 
     * @param className
     *            ??+?? "org.jfree.chart.ChartFactory"
     * @return the class
     * @throws ClassNotFoundException
     *             the class not found exception
     * @since 1.0.7
     */
    public static Class<?> loadClass(String className) throws ClassNotFoundException {
        return Class.forName(className);// JVM
    }

    /**
     * ??.
     * 
     * @param obj
     *            
     * @param klass
     *            
     * @return  obj  true
     * @see java.lang.Class#isInstance(Object)
     */
    public static boolean isInstance(Object obj, Class<?> klass) {
        return klass.isInstance(obj);
    }

    /**
     * ??.
     * 
     * @param ownerClass
     *            class
     * @return true
     * @see java.lang.Class#getModifiers()
     * @see java.lang.reflect.Modifier#isInterface(int)
     */
    public static boolean isInterface(Class<?> ownerClass) {
        // ?? Java 
        int flag = ownerClass.getModifiers();
        // ??
        return Modifier.isInterface(flag);
    }

    /**
     * ??,?,? paramValues null  null.
     * 
     * @param paramValues
     *            ?
     * @return ? paramValues null  null
     * @see org.apache.commons.lang3.ClassUtils#toClass(Object...)
     * @since 1.1.1
     */
    public static Class<?>[] toClass(Object... paramValues) {
        return org.apache.commons.lang3.ClassUtils.toClass(paramValues);
    }
}