适用范围:当我们在jsp页面需要接收很多值的时候,如果用request.getParameter(属性名)一个一个写的话那就太麻烦了,于是我想是 否能用反射写个工具类来简化这样的代码,经过1个小时的代码修改调试,终于雏形出来了,很高兴调试成功,呵呵,代码贴出来.

package com.letv.uts2.utcServer.util;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

/**
 * Created by IntelliJ IDEA.
 * User: haoshihai
 * Date: 13-3-14
 * Time: 下午3:09
 * To change this template use File | Settings | File Templates.
 */
public class WrapperModel {
    private static final Logger log = LoggerFactory.getLogger(WrapperModel.class);
    String userName;
    String password;

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public  static <T> T doWrapper(Class c, Map<String, Object> map) throws Exception {
        T t = (T) c.newInstance();
        try {
            Set<Map.Entry<String, Object>> set = map.entrySet();
            for (Map.Entry<String, Object> entry : map.entrySet()) {
                String fileName = entry.getKey();
                Object value = entry.getValue();
                log.info(“fileName={},value={}”, new Object[]{fileName, value});
                Method get_Method = c.getMethod(“get” + getMethodName(fileName));  //获取getMethod方法
                Method set_Method = c.getMethod(“set” + getMethodName(fileName), get_Method.getReturnType());//获得属性get方法
                Class<?> clazz = get_Method.getReturnType();
                String type = clazz.getName(); //获取返回值名称
                if (type.equals(“long”))
                    set_Method.invoke(t, Long.valueOf(value.toString()));  //对于类型 long
                else if (type.equals(“int”) || type.equals(“java.lang.Integer”))//对于int 类型
                    set_Method.invoke(t, Integer.valueOf(value.toString()));
                else if (“java.lang.String”.equals(type))
                    set_Method.invoke(t,value);
                else set_Method.invoke(t, c.cast(value));//其他类型调用class.cast方法
            }
        } catch (Exception e) {
            log.equals(“property is errorr!” + e.toString());
        }
        return t;
    }

    // 把一个字符串的第一个字母大写、效率是最高的、

    private static String getMethodName(String fildeName) {
        byte[] items = fildeName.getBytes();
        items[0] = (byte) ((char) items[0] – \’a\’ + \’A\’);
        return new String(items);
    }

    public static void main(String args[]) throws Exception {
        Map map = new HashMap();
        map.put(“userName”, “jim”);
        map.put(“password”, “tom”);
        WrapperModel w2 = (WrapperModel) WrapperModel.doWrapper(WrapperModel.class, map);
        System.out.print(w2.getPassword()+”—-“+w2.getUserName());
    }
}

———————————————————————————————

package com.student.util;

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

import javax.servlet.http.HttpServletRequest;

public class BuildBeanUtil {
    @SuppressWarnings(“unchecked”)
    public <T> T buildBean(HttpServletRequest request,Class<T> beanClass) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException{
        //beanClass set方法
        List<Method> setMethods=new ArrayList<Method>();
        //beanClass set方法名
        List<String> setMethodNames=new ArrayList<String>();
        //beanClass 属性名
        List<String> propertyNames=new ArrayList<String>();
        //表单数据
        List<String> formValues=new ArrayList<String>();
        //1、获得该JavaBean的所有的set方法
        Method[] methods=beanClass.getMethods();
        for(Method m:methods){
            if(m.getName().indexOf(“set”)==0){
                setMethods.add(m);
            }
        }
        //2、实例化该javaBean
        Object beanObj=beanClass.newInstance();
        //3、循环set方法数组
        for(Method m:setMethods){
            String methodName=m.getName();
            //3-1、获得方法名
            setMethodNames.add(methodName);
            //3-2、通过方法名推测出属性名
            String name=methodName.substring(3).toLowerCase();
            propertyNames.add(name);
        }
        //3-3、通过request.getParameter(属性名)获得表单数据
        for(String p:propertyNames){
            String value=request.getParameter(p);
            formValues.add(value);
        }
        //3-4、将表单数据转型成为正确的类型，该类型为此set方法的第一个参数的类型
        for(int i=0;i<setMethods.size();i++){
            Method m=setMethods.get(i);
            String type=m.getGenericParameterTypes()[0].toString();
            
            String value=formValues.get(i);
            //判断参数数据类型
//3-5、调用上面实例化的javaBean的此set方法
            if(type.equals(“class java.lang.String”)){
                m.invoke((T)beanObj, value);
            }else if(type.equals(“class java.lang.Integer”)){
                m.invoke((T)beanObj, Integer.parseInt(value));
            }
        }
        //4、返回该javaBean
        return (T) beanObj;
    }
    
}