Mybatis学习笔记16 - bind标签

1、${}拼串进行模糊查询,不安全

示例代码:

接口定义:
package com.mybatis.dao; import com.mybatis.bean.Employee; import java.util.List; public interface EmployeeMapper {
public List<Employee> getEmpsTestInnerParameter(Employee employee);
} mapper定义:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.mybatis.dao.EmployeeMapper">
<select id="getEmpsTestInnerParameter" resultType="com.mybatis.bean.Employee">
<if test="_databaseId=='mysql'">
select * from tbl_employee
<if test="_parameter!=null">
<!--模糊查询,${}可以进行拼串,但是这种方式不安全-->
where last_name like '%${lastName}%'
</if>
</if>
<if test="_databaseId=='oracle'">
select * from employees
<if test="_parameter!=null">
where last_name = #{_parameter.lastName}
</if>
</if>
</select>
</mapper> 测试代码:
package com.mybatis.demo; import com.mybatis.bean.Department;
import com.mybatis.bean.Employee;
import com.mybatis.dao.EmployeeMapper;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Test; import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List; public class MyTest {
public SqlSessionFactory getSqlSessionFactory() throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
return new SqlSessionFactoryBuilder().build(inputStream);
} @Test
public void test() throws IOException {
SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
SqlSession openSession = sqlSessionFactory.openSession(true);
try {
EmployeeMapper mapper = openSession.getMapper(EmployeeMapper.class);
Employee employee = new Employee("e");
List<Employee> list = mapper.getEmpsTestInnerParameter(employee);
for (Employee emp : list) {
System.out.println(emp);
}
} finally {
openSession.close();
}
}
}

2、使用bind标签进行模糊查询

示例代码一:

接口定义:
package com.mybatis.dao; import com.mybatis.bean.Employee; import java.util.List; public interface EmployeeMapper {
public List<Employee> getEmpsTestInnerParameter(Employee employee);
} mapper定义:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.mybatis.dao.EmployeeMapper">
<select id="getEmpsTestInnerParameter" resultType="com.mybatis.bean.Employee">
<!-- bind:可以将OGNL表达式的值绑定到一个变量中,方便后来引用这个变量的值 -->
<bind name="_lastName" value="'%'+lastName+'%'"/>
<if test="_databaseId=='mysql'">
select * from tbl_employee
<if test="_parameter!=null">
where last_name like #{_lastName}
</if>
</if>
<if test="_databaseId=='oracle'">
select * from employees
<if test="_parameter!=null">
where last_name = #{_parameter.lastName}
</if>
</if>
</select>
</mapper> 测试代码:
package com.mybatis.demo; import com.mybatis.bean.Department;
import com.mybatis.bean.Employee;
import com.mybatis.dao.EmployeeMapper;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Test; import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List; public class MyTest {
public SqlSessionFactory getSqlSessionFactory() throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
return new SqlSessionFactoryBuilder().build(inputStream);
} @Test
public void test() throws IOException {
SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
SqlSession openSession = sqlSessionFactory.openSession(true);
try {
EmployeeMapper mapper = openSession.getMapper(EmployeeMapper.class);
Employee employee = new Employee("e");
List<Employee> list = mapper.getEmpsTestInnerParameter(employee);
for (Employee emp : list) {
System.out.println(emp);
}
} finally {
openSession.close();
}
}
}

示例代码二:

接口定义:
package com.mybatis.dao; import com.mybatis.bean.Employee; import java.util.List; public interface EmployeeMapper {
public List<Employee> getEmpsTestInnerParameter(Employee employee);
} mapper定义:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.mybatis.dao.EmployeeMapper">
<select id="getEmpsTestInnerParameter" resultType="com.mybatis.bean.Employee">
<!-- bind:可以将OGNL表达式的值绑定到一个变量中,方便后来引用这个变量的值 -->
<!--_代表任意一个字符-->
<bind name="_lastName" value="'_'+lastName+'%'"/>
<if test="_databaseId=='mysql'">
select * from tbl_employee
<if test="_parameter!=null">
where last_name like #{_lastName}
</if>
</if>
<if test="_databaseId=='oracle'">
select * from employees
<if test="_parameter!=null">
where last_name = #{_parameter.lastName}
</if>
</if>
</select>
</mapper> 测试代码:
package com.mybatis.demo; import com.mybatis.bean.Department;
import com.mybatis.bean.Employee;
import com.mybatis.dao.EmployeeMapper;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Test; import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List; public class MyTest {
public SqlSessionFactory getSqlSessionFactory() throws IOException {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
return new SqlSessionFactoryBuilder().build(inputStream);
} @Test
public void test() throws IOException {
SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
SqlSession openSession = sqlSessionFactory.openSession(true);
try {
EmployeeMapper mapper = openSession.getMapper(EmployeeMapper.class);
Employee employee = new Employee("i");
List<Employee> list = mapper.getEmpsTestInnerParameter(employee);
for (Employee emp : list) {
System.out.println(emp);
}
} finally {
openSession.close();
}
}
}
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