Java反射_JDBC操作数据

使用反射 来操作  这里是练习反射的使用数据库工具类

private static final String DRIVER = "com.mysql.jdbc.Driver";
    private static final String USER = "root";
    private static final String PW = "1234";
    private static final String URL="jdbc:mysql://localhost:3306/reflction";
    /**
     * 链接数据库
     * @return
     */
    public static Connection getConnection(){
        try {
            Class.forName(DRIVER);
            Connection con = DriverManager.getConnection(URL, USER, PW);
            System.out.println("Connection OK .....");
            return con;
        } catch (Exception e) {
            System.out.println("Connection error...");
            e.printStackTrace();
        }
        return null;
    }

public Object getById(Class clazz, Integer id) throws Exception{
Object obj = clazz.newInstance();//实列一个
//创建链接
Connection con = JdbcUtils.getConnection();
//获取实体的名字 需要拼接 从最后一个点开始
String tablename = clazz.getName().substring(clazz.getName().lastIndexOf("."));
//拼接sql 语句
String sql = "select * from "+tablename+" where id=?";

try {
PreparedStatement psmt = con.prepareStatement(sql);
psmt.setInt(1, id);
//查到结果集
ResultSet rs = psmt.executeQuery();
//遍历结果
while(rs.next()){
//得到所有属性
Field[] fields = clazz.getDeclaredFields();
for (Field field : fields) {//遍历属性
//获取属性名
String fname = field.getName();
//获取属性类型 int
Class type = field.getType();
//
Method rsGetMethod = ResultSet.class.getMethod("getObject", String.class);
Object value = rsGetMethod.invoke(rs, fname);
//更改修饰符权限
field.setAccessible(true);
field.set(obj, value);
}

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原文地址：http://blog.csdn.net/u010982856/article/details/40151021