8.mybatis动态SQL模糊查询 (多参数查询,使用parameterType)
多参数查询,使用parameterType。实例:
用户User[id, name, age]
1.mysql建表并插入数据
2.Java实体类
public class User { public User() { } public User(int id, String name, int age) { super(); this.id = id; this.name = name; this.age = age; } private int id; private String name; private int age; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } @Override public String toString() { return "User [id=" + id + ", name=" + name + ", age=" + age + "]"; } }
3.创建查询参数实体类
/** * 模糊查询User的类 * @author Administrator * */ public class SelectUserCondition { private String name;//姓名 private int minAge;//最小年龄 private int maxAge;//最大年龄 public SelectUserCondition() { super(); } public SelectUserCondition(String name, int minAge, int maxAge) { super(); this.name = name; this.minAge = minAge; this.maxAge = maxAge; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getMinAge() { return minAge; } public void setMinAge(int minAge) { this.minAge = minAge; } public int getMaxAge() { return maxAge; } public void setMaxAge(int maxAge) { this.maxAge = maxAge; } }
4.sql查询的配置文件selectUserMapper.xml
<mapper namespace="com.mlxs.mybatis.test7.selectUserMapper"> <!-- 动态sql,模糊查询 parameterType为查询条件实体
-->
<select id="getConditionUser" parameterType="SelectUserCondition" resultType="User">
SELECT * FROM users WHERE <if test='name != "%null%"'> NAME LIKE #{name} AND </if> age BETWEEN #{minAge} AND #{maxAge}
</select>
</mapper>
5.测试类:
/** * 动态sql模糊查询 * * 注意:当name=null时,"%"+name+"%"=%null% * @author 魅力_小生 * */ public class _Test7SelectConditionUser { @Test public void getConditionUser(){ //创建session,设置事务为true SqlSession session = MyBatisUtil.getSessionFactory().openSession(true); String statement = "com.mlxs.mybatis.test7.selectUserMapper.getConditionUser"; //定义查询条件实体 SelectUserCondition condition = new SelectUserCondition("%a%", 20, 100); List<User> ulist = session.selectList(statement, condition); System.out.println("userList--->"+ulist); session.close(); } }
6.结果:
userList--->[User [id=3, name=update2, age=100], User [id=5, name=add1, age=23]]
逃避不一定躲得过,面对不一定最难过