所以如下这种写法就是错误的，这样是无法注入的，在使用该变量的时候会导致空指针错误： @Autowired private static StudentMapper studentMapper; Spring...解决方法就是加上非静态的set方法，如下： private static StudentMapper studentMapper; public StudentMapper getStudentMapper...() { return studentMapper; } @Autowired public void setStudentMapper(StudentMapper studentMapper...) { this.studentMapper = studentMapper; }
studentMapper = sqlSession1.getMapper(StudentMapper.class); Student student = studentMapper.selectByPrimaryKey...studentMapper = sqlSession1.getMapper(StudentMapper.class); Student student = studentMapper.selectByPrimaryKey...studentMapper2 = sqlSession2.getMapper(StudentMapper.class); Student student2 = studentMapper2.selectByPrimaryKey...studentMapper = sqlSession1.getMapper(StudentMapper.class); Student student = studentMapper.selectByPrimaryKey...studentMapper = sqlSession1.getMapper(StudentMapper.class); Student student = studentMapper.selectByPrimaryKey
studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2... studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2... studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2....getMapper(StudentMapper.class); StudentMapper studentMapper3 = sqlSession3.getMapper(StudentMapper.class... studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2
studentMapper1 = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2
studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2
studentMapper = sqlSession.getMapper(StudentMapper.class); Student search = new Student();...studentMapper = sqlSession.getMapper(StudentMapper.class); Student student = new Student();...studentMapper = sqlSession.getMapper(StudentMapper.class); Student student = new Student();...studentMapper = sqlSession.getMapper(StudentMapper.class); Student student = new Student();...studentMapper = sqlSession.getMapper(StudentMapper.class); Student search = new Student();
"/> 4.2 StudentMapper.xml <?...= "classpath:applicationContext.xml") public class StudentMapperTest { @Autowired private StudentMapper...studentMapper; @Test public void getStudent() { List students = studentMapper.findStudent...(student); } @Test public void deleteStudentById() { studentMapper.deleteStudentById...("20181201"); } @Test public void findById() { Student student = studentMapper.findById
studentMapper = sqlSession.getMapper(StudentMapper.class); // 执行第一次查询 List...studentMapper = sqlSession.getMapper(StudentMapper.class); // 执行第一次查询 List...studentMapper2 = sqlSession2.getMapper(StudentMapper.class); List stus = studentMapper2...studentMapper = sqlSession.getMapper(StudentMapper.class); // 执行第一次查询 Student student...studentMapper1 = sqlSession1.getMapper(StudentMapper.class); Student student2 = studentMapper1.selectByPrimaryKey
接口的实例化对象 StudentMapper studentMapper= (StudentMapper) ac.getBean("studentMapper"); //...接口的实例化对象 StudentMapper studentMapper= (StudentMapper) ac.getBean("studentMapper"); //...接口的实例化对象 StudentMapper studentMapper= (StudentMapper) ac.getBean("studentMapper"); //...接口的实例化对象 StudentMapper studentMapper= (StudentMapper) ac.getBean("studentMapper"); //...接口的实例化对象 StudentMapper studentMapper= (StudentMapper) ac.getBean("studentMapper"); //
studentMapper; @Test public void TestSelect() { List students = studentMapper.selectList...student.setId(1L); student.setName("姬发"); int i = studentMapper.updateById(student);...studentMapper; @Test public void TestDel() { int i = studentMapper.deleteById(1L);...studentMapper; @Test public void TestSelect() { Student student = studentMapper.selectById...studentMapper; @Test public void TestSelect() { List list = new ArrayList()
-- 配置mapper --> StudentMapper.xml"/> </configuration...,DOB) VALUES(#{studId},#{name},#{email},#{dob}) 创建Mapper接口 public interface StudentMapper...studentMapper = sqlSession.getMapper(StudentMapper.class); return studentMapper.findAllStudents...studentMapper = sqlSession.getMapper(StudentMapper.class); return studentMapper.findStudentById...studentMapper = sqlSession.getMapper(StudentMapper.class); studentMapper.insertStudent(student
; @SpringBootTest class MapperTests { @Autowired private StudentMapper studentMapper;...(student); } @Test void del() { int i = studentMapper.deleteById(4);...(student); } @Test void select() { Student student = studentMapper.selectById...; @SpringBootTest class MapperTests { @Autowired private StudentMapper studentMapper;...(student); } @Test void del() { int i = studentMapper.deleteById(4);
student) { int i = studentMapper.insertSelective(student); int j = 10/ 0; // 内层报错抛出异常...studentMapper; @Override @Transactional(propagation = Propagation.REQUIRES_NEW) public int addStudent...student) { int i = studentMapper.insertSelective(student); return i; } } 结果： studentMapper.insertSelective...Student student) { int i = studentMapper.insertSelective(student); return i; } } 结果： studentMapper.insertSelective...(Student student) { int i = studentMapper.insertSelective(student); return i; } } 结果： studentMapper.insertSelective
StudentMapper"> <!...; } // 每次执行前,请空表 @Before public void setUp(){ StudentMapper studentMapper =...SqlSessionUtil.getMapper(StudentMapper.class); studentMapper.clear(); } // 默认执行器...(StudentMapper.class); // 执行批量保存 batchSave(mapper); } // 重用预编译执行器 @Test...[2019-06-13 11:30:38:819][main][DEBUG][o.z.l.m.l.mapper.StudentMapper.save]- ==> Parameters: zhangsan
DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> StudentMapper...DELETE FROM students WHERE id = #{id} 在上面的 XML 文件中，我们定义了一个名为 StudentMapper...studentMapper = sqlSession.getMapper(StudentMapper.class); Student student = new Student(); student.setName...("John"); student.setAge(25); studentMapper.insertStudent(student); sqlSession.commit(); sqlSession.close...接着，我们通过 getMapper 方法获取 StudentMapper 对象，并使用该对象调用 insertStudent 方法将学生对象保存到数据库中。
studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 = sqlSession2...studentMapper1 = sqlSession1.getMapper(StudentMapper.class); StudentMapper studentMapper2 =
{ StudentMapper INSTANCE = Mappers.getMapper(StudentMapper.class); @Mapping(source = "gender.name...可以手动指定格式化的方法： @Mapper public interface StudentMapper { StudentMapper INSTANCE = Mappers.getMapper...{ StudentMapper INSTANCE = Mappers.getMapper(StudentMapper.class); @Mapping(source = "gender.name...{ StudentMapper INSTANCE = Mappers.getMapper(StudentMapper.class); @Mapping(source = "student.gender.name...3.默认值 @Mapper public interface StudentMapper { StudentMapper INSTANCE = Mappers.getMapper(StudentMapper.class
ofType="com.example.pojo.Student" select="com.example.mapper.StudentMapper2...新增持久层接口方法 新增StudentMapper3.java接口 package com.example.mapper; import com.example.pojo.Student; import...java.util.List; public interface StudentMapper3 { // 查询所有学生 List findAll(); } 新增ClassesMapper3...新增测试方法 // 分解式查询一对一 @Test public void testFindAllStudent2(){ StudentMapper3 studentMapper3...= session.getMapper(StudentMapper3.class); List all = studentMapper3.findAll();
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