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【java实例】自己动手实现IOC和MVC（五）

下面介绍几个工具类会在项目中用到 ① BeanUtils.Java 对java反射中操作的一些封装

package com.ajunframework.beans.utils;

import java.lang.reflect.Constructor;

import java.lang.reflect.Field;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;

import java.lang.reflect.Modifier;

/**

* @author harries

* @http://www.liuhaihua.cn

*/

public class BeanUtils {

    /**

     * 实例化一个class

     * @param <T>

     * @param clazz Person.class

     * @return

     */

    public static <T> T instanceClass(Class<T> clazz){

        if(!clazz.isInterface()){

            try {

                return clazz.newInstance();

            } catch (InstantiationException e) {

                e.printStackTrace();

            } catch (IllegalAccessException e) {

                e.printStackTrace();

            }

        }

        return null;

    }

    /**

     * 通过构造函数实例化

     * @param <T>

     * @param ctor

     * @param args

     * @return

     * @throws IllegalArgumentException

     * @throws InstantiationException

     * @throws IllegalAccessException

     * @throws InvocationTargetException

     */

    public static <T> T instanceClass(Constructor<T> ctor, Object... args) throws IllegalArgumentException, InstantiationException, IllegalAccessException, InvocationTargetException{

        makeAccessible(ctor);

        return ctor.newInstance(args);//调用构造方法实例化

    }

    /**

     * 查找某个class的方法

     * @param clazz

     * @param methodName

     * @param paramTypes

     * @return

     * @throws SecurityException

     * @throws NoSuchMethodException

     */

    public static  Method findMethod(Class<?> clazz, String methodName, Class<?>... paramTypes){

        try {

            return clazz.getMethod(methodName, paramTypes);

        } catch (NoSuchMethodException e) {

            return findDeclaredMethod(clazz, methodName, paramTypes);//返回共有的方法

        }

    }

    public static Method findDeclaredMethod(Class<?> clazz, String methodName, Class<?>[] paramTypes){

        try {

            return clazz.getDeclaredMethod(methodName, paramTypes);

        }

        catch (NoSuchMethodException ex) {

            if (clazz.getSuperclass() != null) {

                return findDeclaredMethod(clazz.getSuperclass(), methodName, paramTypes);

            }

            return null;

        }

    }

    public static Method [] findDeclaredMethods(Class<?> clazz){

            return clazz.getDeclaredMethods();

    }

    public static void makeAccessible(Constructor<?> ctor) {

        if ((!Modifier.isPublic(ctor.getModifiers()) || !Modifier.isPublic(ctor.getDeclaringClass().getModifiers()))

                && !ctor.isAccessible()) {

            ctor.setAccessible(true);//如果是私有的设置为true 使其可以访问

        }

    }

    public static Field[] findDeclaredFields(Class<?> clazz){

        return clazz.getDeclaredFields();

    }

}

②BeanWrapper.java 用于设置bean中的属性值

package com.ajunframework.beans.utils;

import java.beans.IntrospectionException;

import java.beans.PropertyDescriptor;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;

/**

* @author harries

* @http://www.liuhaihua.cn

*/

public class BeanWrapper {

    private Object object;

    public BeanWrapper(Object object) {

        super();

        this.object = object;

    }

    public void setPropertyValue(String name,Object value){

            try {

                PropertyDescriptor pd = new PropertyDescriptor(name,this.object.getClass());

                Method setMethod = pd.getWriteMethod();

                setMethod.invoke(object, value);

            } catch (SecurityException e) {

                e.printStackTrace();

            } catch (IllegalArgumentException e) {

                e.printStackTrace();

            } catch (IllegalAccessException e) {

                e.printStackTrace();

            } catch (InvocationTargetException e) {

                e.printStackTrace();

            }catch (IntrospectionException e) {

                e.printStackTrace();

            }

    }

    public Object getPropertyValue(String name){

        Object value=null;

        try {

            PropertyDescriptor pd = new PropertyDescriptor(name,this.object.getClass());

            Method getMethod = pd.getReadMethod();

            value = getMethod.invoke(object);

        } catch (IllegalArgumentException e) {

            e.printStackTrace();

        } catch (IntrospectionException e) {

            e.printStackTrace();

        } catch (IllegalAccessException e) {

            e.printStackTrace();

        } catch (InvocationTargetException e) {

            e.printStackTrace();

        }

        return value;

    }

}

③PubConstant.java 读取constant.properties文件

package com.ajunframework.beans.utils;

import java.io.IOException;

import java.util.Properties;

/**

* @author harries

* @http://www.liuhaihua.cn

**/

public class PubConstant {

    private static Properties properties= new Properties();

    static{

        try {

            properties.load(PubConstant.class.getClassLoader().getResourceAsStream("constant.properties"));

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

    public static String getValue(String key){

        String value = (String)properties.get(key);

        return value.trim();

    }

}

下一节我们会做个测试对现在的ioc