package coral.base.util; import java.beans.IntrospectionException; import java.beans.PropertyDescriptor; import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.Date; import java.util.HashMap; import java.util.List; import java.util.Map; import wfc.service.database.RecordSet; public class ReflectUtils { /** * 将一个map集合封装成为bean对象 * * @param param * @param clazz * @return */ public static  T MapToBean(Map param, Class clazz) { Object value = null; Class[] paramTypes = new Class[1]; Object obj = null; try { obj = clazz.newInstance(); // 获取类的属性 Field[] declaredFields = clazz.getDeclaredFields(); // 获取父类或接口的公有属性 Field[] superFields = clazz.getSuperclass().getFields(); List list = new ArrayList(); if (declaredFields != null) { list.add(declaredFields); } if (superFields != null) { list.add(superFields); } for (Field[] fields : list) { for (Field field : fields) { String fieldName = field.getName(); // 获取属性对应的值ֵ value = param.get(fieldName); // 把值设置进入对象属性中 这里可能是有属性但是没有相应的set方法，所以要做异常处理 try { PropertyDescriptor pd = new PropertyDescriptor( fieldName, clazz); Method method = pd.getWriteMethod(); method.invoke(obj, new Object[] { value }); } catch (Exception e1) { } } } } catch (Exception e1) { } return (T) obj; } /** * 获取类的所有属性，包括父类和接口 * @param clazz * @return */ public static List getBeanFields(Class clazz) { List list = new ArrayList(); Field[] declaredFields = clazz.getDeclaredFields(); Field[] superFields = clazz.getSuperclass().getFields(); if (declaredFields != null) { list.add(declaredFields); } if (superFields != null) { list.add(superFields); } return list; } /** * 从结果集中获取出值 * @param fieldName * @param rs * @return */ public static Object getFieldValue(String fieldName, ResultSet rs) { Object value = null; try { //捕获值不存在的异常 value = rs.getObject(fieldName); return value; } catch (SQLException e) { //oracle数据库的列都是大写，所以才查找一次 fieldName = fieldName.toLowerCase(); try { value = rs.getObject(fieldName); return value; } catch (SQLException e1) { //结果集中没有对应的值，返回为空 return null; } } } /** * 方法重载， * @param fieldName * @param rs 这个是封装过的结果集 * @return */ public static Object getFieldValue(String fieldName, RecordSet rs) { Object value = null; value = rs.getObject(fieldName); return value; } /** * 方法重载 * @param rs 封装过的结果集 * @param clazz * @return */ public static  T RSToBean(RecordSet rs, Class clazz) { Object obj = null; List list = getBeanFields(clazz); try { obj = clazz.newInstance(); for (Field[] fields : list) { for (Field field : fields) { String fieldName = field.getName(); // String fieldName = field.getName();ֵ Object value = getFieldValue(fieldName, rs); try { PropertyDescriptor pd = new PropertyDescriptor( fieldName, clazz); Method method = pd.getWriteMethod(); method.invoke(obj, new Object[] { value }); } catch (Exception e1) { } } } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } return (T) obj; } /** * 把结果集封装成为bean对象 * @param rs * @param clazz * @return */ public static  T RSToBean(ResultSet rs, Class clazz) { Object obj = null; List list = getBeanFields(clazz); try { while (rs.next()) { obj = clazz.newInstance(); for (Field[] fields : list) { for (Field field : fields) { String fieldName = field.getName(); // String fieldName = field.getName();ֵ Object value = getFieldValue(fieldName, rs); PropertyDescriptor pd = new PropertyDescriptor( fieldName, clazz); Method method = pd.getWriteMethod(); method.invoke(obj, new Object[] { value }); } } } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } return (T) obj; } /** * 把结果集封装成为List * * @param rs * @param clazz * @return */ public static  List RsToList(ResultSet rs, Class clazz) { ArrayList objList = new ArrayList(); // 获取所有的属性 List list = getBeanFields(clazz); try { while (rs.next()) { // 定义临时变量 Object tempObeject = clazz.newInstance(); // 添加到属性中 for (Field[] fields : list) { for (Field field : fields) { String fieldName = field.getName(); // 获取属性值ֵ Object value = getFieldValue(fieldName, rs); PropertyDescriptor pd = new PropertyDescriptor( fieldName, clazz); Method method = pd.getWriteMethod(); method.invoke(tempObeject, new Object[] { value }); } } objList.add((T) tempObeject); } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } return objList; } } 

 package com.util; import com.entity.Student; import javax.servlet.ServletRequest; import java.lang.reflect.Field; import java.lang.reflect.Method; import java.text.SimpleDateFormat; import java.util.Enumeration; /** * Created by wq on 2017/8/30. */ public class BeanOperateTools { /* 利用反射进行所以请求参数的设置，要求参数名与属性名一致 */ /** * * @param obj * @param req * @param datePatern 将字符串变为日期时间格式化的字符串 * @throws Exception */ public static void setValue(Object obj, ServletRequest req,String datePatern) throws Exception {//设置属性的内容 { System.out.println("进了setValue方法....."); //取得class对象 Class cls = obj.getClass(); //取得输入的全部参数名称 Enumeration enu = req.getParameterNames(); //循环输入的全部参数名称 while (enu.hasMoreElements()) { String paramName = enu.nextElement();//取得参数名称 String paramValue = req.getParameter(paramName); //取得属性的类型是为了取得参数的类型，以确定method方法和是否转型 Field field = cls.getDeclaredField(paramName); //取得指定名称的属性 (实体类里面 //取得指定的操作方法，以满足反射调用 Method method = cls.getMethod("set"+StringTools.initcap(paramName),field.getType()); //根据类型进行数据的转换，同时调用setter设置数据 //取得类型 String fieldType=field.getType().getSimpleName(); if ("string".equalsIgnoreCase(fieldType)) { method.invoke(obj,paramValue); }else if ("integer".equalsIgnoreCase(fieldType)||"int".equalsIgnoreCase(fieldType)){ method.invoke(obj,Integer.parseInt(paramValue)); }else if ("double".equalsIgnoreCase(fieldType)){ method.invoke(obj,Double.parseDouble(paramValue)); }else if ("date".equalsIgnoreCase(fieldType)){ method.invoke(obj,new SimpleDateFormat(datePatern).parse(paramValue)); } } } } } 

 package com.servlet; import com.entity.Student; import com.sun.xml.internal.bind.v2.runtime.reflect.opt.FieldAccessor_Double; import com.util.BeanOperateTools; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Enumeration; /** * Created by wq on 2017/8/22. */ @WebServlet(name = "studentServlet", urlPatterns = {"/StudentServlet"}) public class StudentServlet extends HttpServlet { //private Student stu = new Student(); private Student student=new Student(); public Student getStudent() { return student; } public void setStudent(Student student) { this.student = student; } -------此处模仿依赖注入 @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { req.setCharacterEncoding("UTF-8"); try { BeanOperateTools.setValue(this.getStudent(),req,"yyyy-MM-dd"); } catch (Exception e) { e.printStackTrace(); } req.setAttribute("student",this.student); req.getRequestDispatcher("student_insert_do.jsp").forward(req,resp); // Class cls= this.stu.getClass(); } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { this.doGet(req, resp); } public String initcap(String str) {//首字母大写 return str.substring(0, 1).toUpperCase().concat(str.substring(1).toLowerCase()); } } 

 <%-- Created by IntelliJ IDEA. User: wq Date: 2017/8/21 Time: 23:25 To change this template use File | Settings | File Templates. --%><%@ page contentType="text/html;charset=UTF-8" language="java" %>   
 姓名:
 年龄:
 成绩:

 <%-- Created by IntelliJ IDEA. User: wq Date: 2017/8/21 Time: 23:25 To change this template use File | Settings | File Templates. --%><%@ page contentType="text/html;charset=UTF-8" language="java" %>   
姓名：${student.name}
年龄：${student.age}
成绩：${student.score}