JavaBean
就是实体类
JavaBean有特定的写法:
- 必须要有一个无参构造
- 属性必须私有化
- 必须有对应的get/set方法
一般用来和数据库的字段做映射:ORM
ORM:对象关系映射
- 表—–>类
- 字段—->属性
- 行记录—->对象
例如:
| id | name | age | address || —- | —- | —- | ——- || 1 | 1 | 12 | 西安 || 2 | 2 | 121 | 西安 || 3 | 3 | 12 | 西安 |
class People{private int id;private String name;private int age;private String address;}class A{new people(1,"1",12,"西安");new people(2,"2",121,"西安");new people(3,"3",12,"西安");}
jsp标签也可以对实体类创建对象并赋值:
<jsp:useBean id="people" class="com.kuang.pojo.People" scope="page"/><jsp:setProperty name="people" property="id" value="1"/><jsp:setProperty name="people" property="name" value="1"/><jsp:setProperty name="people" property="age" value="12"/><jsp:setProperty name="people" property="address" value="西安"/><%--获取对象中的值--%>id:<jsp:getProperty name="people" property="id"/>姓名:<jsp:getProperty name="people" property="name"/>年龄:<jsp:getProperty name="people" property="age"/>地址:<jsp:getProperty name="people" property="address"/>