Java中class工具类--Java免费学习网_JAVA_编程开发_程序员俱乐部

package com.util;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;

public class ClassUtils {  
   
    /** 
     * 获取对象的属性值 
     *  
     * @param object 对象实例 
     * @param property 属性名 
     * @return 属性的值 
     */  
    public static Object getObjectProperty(Object object, String property) throws NoSuchMethodException, SecurityException, IllegalArgumentException, IllegalAccessException, InvocationTargetException, NoSuchFieldException {  
        if (object == null)  
            return null;  
        try {  
            return getClassGetter(object.getClass(), property).invoke(object, new Object[0]);  
        } catch (NoSuchMethodException e) {
         Object o = object.getClass().getField(property).get(object);  
         System.out.println(o);
            return o;
        }  
    }  
  
    /** 
     * 查找getXXX与isXXX的属性Getter方法 
     *  
     * @param clazz 类元   http://www.javalearns.com/
     * @param property 属性名 
     * @return 属性Getter方法 
     */  
    public static Method getClassGetter(Class clazz, String property) throws NoSuchMethodException, SecurityException {  
       // Assert.assertNotNull(clazz, "class不能为空！");  
        //Assert.assertNotEmpty(property, "property不能为空！");  
        property = property.trim();  
        String upper = property.substring(0, 1).toUpperCase() + property.substring(1);  
        try {  
            Method getter = getClassMethod(clazz, "get" + upper);  
            //Assert.assertTrue(getter.getReturnType() != Void.class, "getter返回值类型不能为void！");  
            return getter;  
        } catch (NoSuchMethodException e1) {  
            try {  
                Method getter = getClassMethod(clazz, "is" + upper);  
               // Assert.assertTrue(getter.getReturnType() != Void.class, "getter返回值类型不能为void！");  
                return getter;  
            } catch (NoSuchMethodException e2) {  
                Method getter = getClassMethod(clazz, property);  
                //Assert.assertTrue(getter.getReturnType() != Void.class, "getter返回值类型不能为void！");  
                return getter;  
            }  
        }  
    }  
  
    /** 
     * 获取类的方法 (保证返回方法的公开性) 
     *  
     * @param clazz 类 
     * @param methodName 方法名  http://www.javalearns.com/
     * @return 公开的方法 
     */  
    public static Method getClassMethod(Class clazz, String methodName) throws NoSuchMethodException, SecurityException {  
        //Assert.assertNotNull(clazz, "class不能为空！");  
        //Assert.assertNotNull(methodName, "methodName不能为空！");  
        try {  
            return searchPublicMethod(clazz.getInterfaces(), methodName);  
        } catch (NoSuchMethodException e1) {  
            try {  
                return searchPublicMethod(clazz.getClasses(), methodName);  
            } catch (NoSuchMethodException e2) {  
                return clazz.getMethod(methodName, new Class[0]);  
            }  
        }  
    }  
  
    // 查找公开的方法 (辅助方法)  
    private static Method searchPublicMethod(Class[] classes, String methodName) throws NoSuchMethodException, SecurityException {  
        if (classes != null && classes.length > 0) {  
            for (int i = 0, n = classes.length; i < n; i ++) {  
                Class cls = classes[i];  
                if ((cls.getModifiers() & Modifier.PUBLIC) == 1) { // 首先保证类是公开的  
                    try {  
                        Method method = cls.getMethod(methodName, new Class[0]);  
                        if ((method.getModifiers() & Modifier.PUBLIC) == 1) // 再保证方法是公开的  
                            return method;  
                    } catch (NoSuchMethodException e) {  
                        // ignore, continue  
                    }  
                }  
            }  
        }  
        throw new NoSuchMethodException(); // 未找到方法  
    }  
  
} 
文章转载自  http://www.javalearns.com/Html/?1561.html

更多Java学习文章请访问  Java免费学习网 http://www.javalearns.com