mybatis学习笔记2.doc

如有侵权，请联系网站删除，仅供学习与交流mybatis学习笔记2【精品文档】第 19 页第十六章 回顾SQL99中的连接查询 1）内连接 2）外连接 3）自连接 第十七章 回顾hibernate多表开发1）一对一2）一对多3）多对多第十八章 mybatis一对一映射【学生与身份证】1）参见<<一对一图示.JPG>>2）创建students.sql和cards.sql drop table students;drop table cards;create table cards(idint(5)primary key,num varchar(20);create table students(idint(5)primary key,name varchar(10),cid int(5),constraint cid_fk foreign key(cid) references cards(id);insert into cards(id,num) values(1,'111');insert into students(id,name,cid) values(1,'哈哈',1);3）创建Students.java和Card.java public class Card private Integer id;private String num;private Student student;public Card()public Integer getId() return id;public void setId(Integer id) this.id = id;public String getNum() return num;public void setNum(String num) this.num = num;public Student getStudent() return student;public void setStudent(Student student) this.student = student;public class Student private Integer id;private String name;private Card card;public Student()public Integer getId() return id;public void setId(Integer id) this.id = id;public String getName() return name;public void setName(String name) this.name = name;public Card getCard() return card;public void setCard(Card card) this.card = card;4）创建StudentMapper.xml和CardMapper.xml CardMapper.xml<?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="cardNamespace"><resultMap type="cn.itcast.javaee.mybatis.one2one.Card" id="cardMap"><id property="id" column="id" /><result property="num" column="num" /></resultMap></mapper> StudentMapper.xml<?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="studentNamespace"><resultMap type="cn.itcast.javaee.mybatis.one2one.Student" id="studentMap"><id property="id" column="id" /><result property="name" column="name"/><association property="card" resultMap="cardNamespace.cardMap"/></resultMap><select id="findById" parameterType="int" resultMap="studentMap">select s.id,s.name,c.id,c.numfrom students s inner join cards con s.cid = c.id and s.id = #id</select></mapper>5）创建StudentCardDao.java public class StudentCardDao /* * 查询1号【学生】 */public Student findById(int id) throws ExceptionSqlSession sqlSession = null;trysqlSession = MybatisUtil.getSqlSession();return sqlSession.selectOne("studentNamespace.findById",id);catch(Exception e)e.printStackTrace();throw e;finallyMybatisUtil.closeSqlSession();public static void main(String args) throws ExceptionStudentCardDao dao = new StudentCardDao();Student student = dao.findById(1);System.out.println(student.getId()+":"+student.getName();System.out.println(student.getCard().getId()+":"+student.getCard().getNum();第十九章 mybatis一对多映射【班级与学生】1）参见<<一对多图示.JPG>>2）创建grades.sql和students.sqldrop table students;drop table grades;create table grades(gidint(5)primary key,gname varchar(10) );create table students(sidint(5)primary key,sname varchar(10), sgid int(5), constraint sgid_fk foreign key(sgid) references grades(gid);insert into grades(gid,gname) values(1,'java');insert into students(sid,sname,sgid) values(1,'哈哈',1);insert into students(sid,sname,sgid) values(2,'呵呵',1);3）创建Grade.java和Student.sql/* * 班级（单方） * author AdminTC */public class Grade private Integer id;private String name;private List<Student> studentList = new ArrayList<Student>();public Grade()public Integer getId() return id;public void setId(Integer id) this.id = id;public String getName() return name;public void setName(String name) this.name = name;public List<Student> getStudentList() return studentList;public void setStudentList(List<Student> studentList) this.studentList = studentList;/* * 学生（多方） * author AdminTC */public class Student private Integer id;private String name;private Grade grade;public Student()public Integer getId() return id;public void setId(Integer id) this.id = id;public String getName() return name;public void setName(String name) this.name = name;public Grade getGrade() return grade;public void setGrade(Grade grade) this.grade = grade;4）创建GradeMapper.xml和StudentMapper.xml GradeMapper.xml<?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="gradeNamespace"><resultMap type="cn.itcast.javaee.mybatis.one2many.Grade" id="gradeMap"><id property="id" column="gid" /><result property="name" column="gname"/><collection property="studentList" resultMap="studentNamespace.studentMap"/></resultMap><select id="findGradeByName" parameterType="string" resultMap="gradeMap">select g.gid,g.gname,s.sid,s.snamefrom grades g,students swhere g.gid = s.sgidand s.sname = #name</select></mapper> StudentMapper.xml<?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="studentNamespace"><resultMap type="cn.itcast.javaee.mybatis.one2many.Student" id="studentMap"><id property="id" column="sid" /><result property="name" column="sname"/><association property="grade" resultMap="gradeNamespace.gradeMap"/></resultMap><select id="findAllByName" parameterType="string" resultMap="studentMap">select s.sid,s.sname,g.gid,g.gnamefrom grades g,students swhere g.gid = s.sgidand g.gname = #name</select></mapper>5）创建GradeStudentDao.javapublic class GradeStudentDao /* * 查询java班级有哪些【学生】 */public List<Student> findAllByName(String name) throws ExceptionSqlSession sqlSession = null;trysqlSession = MybatisUtil.getSqlSession();return sqlSession.selectList("studentNamespace.findAllByName",name);catch(Exception e)e.printStackTrace();throw e;finallyMybatisUtil.closeSqlSession();/* * 查询哈哈属于哪个【班级】 */public Grade findGradeByName(String name) throws ExceptionSqlSession sqlSession = null;trysqlSession = MybatisUtil.getSqlSession();return sqlSession.selectOne("gradeNamespace.findGradeByName",name);catch(Exception e)e.printStackTrace();throw e;finallyMybatisUtil.closeSqlSession();public static void main(String args) throws ExceptionGradeStudentDao dao = new GradeStudentDao();List<Student> studentList = dao.findAllByName("java");for(Student s : studentList)System.out.println(s.getId()+":"+s.getName()+":"+s.getGrade().getId()+":"+s.getGrade().getName();Grade grade = dao.findGradeByName("哈哈");System.out.println(grade.getId()+":"+grade.getName();第二十章 mybatis多对多映射【学生与课程】1）参见<<多对多图示.JPG>>2）创建students.sql和courses.sql和middles.sqldrop table middles;drop table students;drop table courses;create table students(sid int(5) primary key,sname varchar(10);create table courses(cid int(5) primary key,cname varchar(10);create table middles(sid int(5),cid int(5),primary key(sid,cid);insert into students(sid,sname) values(1,'哈哈');insert into students(sid,sname) values(2,'呵呵');insert into courses(cid,cname) values(1,'java');insert into courses(cid,cname) values(2,'net');insert into middles(sid,cid) values(1,1);insert into middles(sid,cid) values(1,2);insert into middles(sid,cid) values(2,1);insert into middles(sid,cid) values(2,2);select * from students;select * from courses;select * from middles;3）创建Student.java和Course.java/* * 学生(多方) * author AdminTC */public class Student private Integer id;private String name;private List<Course> courseList = new ArrayList<Course>();public Student()public Integer getId() return id;public void setId(Integer id) this.id = id;public String getName() return name;public void setName(String name) this.name = name;public List<Course> getCourseList() return courseList;public void setCourseList(List<Course> courseList) this.courseList = courseList;/* * 课程(多方) * author AdminTC */public class Course private Integer id;private String name;private List<Student> studentList = new ArrayList<Student>();public Course()public Integer getId() return id;public void setId(Integer id) this.id = id;public String getName() return name;public void setName(String name) this.name = name;public List<Student> getStudentList() return studentList;public void setStudentList(List<Student> studentList) this.studentList = studentList;4）创建StudentMapper.xml和CourseMapper.xml StudentMapper.xml<?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="studentNamespace"><resultMap type="cn.itcast.javaee.mybatis.many2many.Student" id="studentMap"><id property="id" column="sid" /><result property="name" column="sname"/></resultMap><select id="findStudentByName" parameterType="string" resultMap="studentMap">select s.sid,s.snamefrom students s,middles m,courses cwhere s.sid = m.sid and m.cid = c.cidand ame = #name</select></mapper> CourseMapper.xml<?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="courseNamespace"><resultMap type="cn.itcast.javaee.mybatis.many2many.Course" id="courseMap"><id property="id" column="cid" /><result property="name" column="cname"/></resultMap><select id="findCourseByName" parameterType="string" resultMap="courseMap">select c.cid,amefrom students s,middles m,courses cwhere s.sid = m.sid and m.cid = c.cidand s.sname = #name</select></mapper>5）创建students.sql和courses.sql和middles.sqlpublic class StudentCourseDao /* * 查询哈哈选学的【课程】 */public List<Course> findCourseByName(String name) throws ExceptionSqlSession sqlSession = null;trysqlSession = MybatisUtil.getSqlSession();return sqlSession.selectList("courseNamespace.findCourseByName",name);catch(Exception e)e.printStackTrace();throw e;finallyMybatisUtil.closeSqlSession();/* * 查询java课程有哪些【学生】 */public List<Student> findStudentByName(String name) throws ExceptionSqlSession sqlSession = null;trysqlSession = MybatisUtil.getSqlSession();return sqlSession.selectList("studentNamespace.findStudentByName",name);catch(Exception e)e.printStackTrace();throw e;finallyMybatisUtil.closeSqlSession();public static void main(String args) throws ExceptionStudentCourseDao dao = new StudentCourseDao();/List<Course> courseList = dao.findCourseByName("哈哈");/for(Course c : courseList)/System.out.println(c.getId()+":"+c.getName();/List<Student> studentList = dao.findStudentByName("java");for(Student s : studentList)System.out.println(s.getId()+":"+s.getName(); 第二十一章 spring + mybatis + mysql/oracle开发1）创建一个spring-mybatis-mysql这么一个javaweb或java工程2）导入spring-ioc，spring-aop，spring-transaction，mybatis，c3p0，mysql/oracle相关的jar包和spring整合mybatis的jar包3）创建students.sql-mysqlcreate table students( sid int(5) primary key, sname varchar(10), ssal double(8,2);4）创建Student.java/* * 学生 * author AdminTC */public class Student private Integer id;/编号private String name;/姓名private Double sal;/薪水public Student()public Student(Integer id, String name, Double sal) this.id = id;this.name = name;this.sal = sal;public Integer getId() return id;public void setId(Integer id) this.id = id;public String getName() return name;public void setName(String name) this.name = name;public Double getSal() return sal;public void setSal(Double sal) this.sal = sal;5）创建StudentMapper.xml<?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="studentNamespace"><resultMap type="cn.itcast.javaee.mybatis.entity.Student" id="studentMap"><id property="id" column="sid" /><result property="name" column="sname"/><result property="sal" column="ssal"/></resultMap><insert id="insert" parameterType="cn.itcast.javaee.mybatis.entity.Student">insert into students(sid,sname,ssal) values(#id,#name,#sal)</insert></mapper>6）创建StudentDao.javapublic class StudentDao private SqlSessionFactory sqlSessionFactory;public void setSqlSessionFactory(SqlSessionFactory sqlSessionFactory) this.sqlSessionFactory = sqlSessionFactory;public void insert(Student student)SqlSession sqlSession = sqlSessionFactory.openSession();sqlSession.insert("studentNamespace.insert",student);/int i = 10/0;public static void main(String args) ApplicationContext ac = new ClassPathXmlApplicationContext(new String"spring.xml");StudentDao studentDao = (StudentDao) ac.getBean("studentDaoID");studentDao.insert(new Student(1,"哈哈",7000D);7）在src目录下创建mybatis.xml<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE configuration PUBLIC "-/mybatis.org/DTD Config 3.0/EN""http:/mybatis.org/dtd/mybatis-3-config.dtd"><configuration><mappers><mapper resource="cn/itcast/javaee/mybatis/entity/StudentMapper.xml"/></mappers></configuration>8）在src目录下创建spring.xml <?xml version="1.0" encoding="UTF-8"?><beans xmlns="http:/www.springframework.org/schema/beans" xmlns:xsi="http:/www.w3.org/2001/XMLSchema-instance" xmlns:context="http:/www.springframework.org/schema/context" xmlns:aop="http:/www.springframework.org/schema/aop" xmlns:tx="http:/www.springframework.org/schema/tx" xmlns:mvc="http:/www.springframework.org/schema/mvc" xsi:schemaLocation=" http:/www.springframework.org/sc