public class ReflectTest {

    public static void main(String[] args) {
        User user = (User) test(
                "userId:1;userName:frank;password:1234;date:1328241269734;count:1",
                User.class);
        System.out.println(user.getUserName());
    }

    private static Object test(String userStr, Class<?> clazz) {
        try {
            String[] str = userStr.split(";");
            Object user = clazz.newInstance();// 初始化一个对象
            Field[] fields = clazz.getDeclaredFields();// 获取该对象所有字段
            for (String str1 : str) {
                for (Field field : fields) {
                    String c = field.getType().getName();// 字段类型
                    if (field.getName().equals(str1.split(":")[0])) {
                        field.setAccessible(true);// 把字段设置为可访问
                        if (c.equals("int")) {
                            field.setInt(user, Integer
                                    .parseInt(str1.split(":")[1]));
                        } else if (c.equals("java.lang.String")) {
                            field.set(user, str1.split(":")[1]);
                        } else if (c.equals("java.lang.long")) {
                            field.setLong(user, Long
                                    .parseLong(str1.split(":")[1]));
                        }
                    }
                }
            }
            return user;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
}