个人觉得JdbcTemplate相较于MyBaits,Hibernate等数据库框架更容易上手,对SQL的操作也更为直观方便,所以在项目中也是一个不错的选择。在Spring Boot开启JdbcTemplate很简单,只需要引入spring-boot-starter-jdbc依赖即可。JdbcTemplate封装了许多SQL操作,具体可查阅官方文档https://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/jdbc/core/JdbcTemplate.html。
引入依赖
spring-boot-starter-jdbc:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
数据库驱动为ojdbc6,数据源采用Druid。具体可参考https://mrbird.cc/Spring-Boot%E4%B8%AD%E4%BD%BF%E7%94%A8Mybatis.html。
代码编写
数据准备:
CREATE TABLE "SCOTT"."STUDENT" (
"SNO" VARCHAR2(3 BYTE) NOT NULL ,
"SNAME" VARCHAR2(9 BYTE) NOT NULL ,
"SSEX" CHAR(2 BYTE) NOT NULL
);
INSERT INTO "SCOTT"."STUDENT" VALUES ('001', 'KangKang', 'M ');
INSERT INTO "SCOTT"."STUDENT" VALUES ('002', 'Mike', 'M ');
INSERT INTO "SCOTT"."STUDENT" VALUES ('003', 'Jane', 'F ');
这里主要演示在Dao的实现类里使用JdbcTemplate,所以其它模块代码的编写就不展示了,具体可参考文末的源码。
StudentDaoImp类代码:
@Repository("studentDao")
public class StudentDaoImp implements StudentDao {
@Autowired
private JdbcTemplate jdbcTemplate;
@Override
public int add(Student student) {
// String sql = "insert into student(sno,sname,ssex) values(?,?,?)";
// Object[] args = { student.getSno(), student.getName(), student.getSex() };
// int[] argTypes = { Types.VARCHAR, Types.VARCHAR, Types.VARCHAR };
// return this.jdbcTemplate.update(sql, args, argTypes);
String sql = "insert into student(sno,sname,ssex) values(:sno,:name,:sex)";
NamedParameterJdbcTemplate npjt = new NamedParameterJdbcTemplate(this.jdbcTemplate.getDataSource());
return npjt.update(sql, new BeanPropertySqlParameterSource(student));
}
@Override
public int update(Student student) {
String sql = "update student set sname = ?,ssex = ? where sno = ?";
Object[] args = { student.getName(), student.getSex(), student.getSno() };
int[] argTypes = { Types.VARCHAR, Types.VARCHAR, Types.VARCHAR };
return this.jdbcTemplate.update(sql, args, argTypes);
}
@Override
public int deleteBysno(String sno) {
String sql = "delete from student where sno = ?";
Object[] args = { sno };
int[] argTypes = { Types.VARCHAR };
return this.jdbcTemplate.update(sql, args, argTypes);
}
@Override
public List<Map<String, Object>> queryStudentsListMap() {
String sql = "select * from student";
return this.jdbcTemplate.queryForList(sql);
}
@Override
public Student queryStudentBySno(String sno) {
String sql = "select * from student where sno = ?";
Object[] args = { sno };
int[] argTypes = { Types.VARCHAR };
List<Student> studentList = this.jdbcTemplate.query(sql, args, argTypes, new StudentMapper());
if (studentList != null && studentList.size() > 0) {
return studentList.get(0);
} else {
return null;
}
}
}
在引入spring-boot-starter-jdbc驱动后,可直接在类中注入JdbcTemplate。由上面代码可发现,对于保存操作有两种不同的方法,当插入的表字段较多的情况下,推荐使用NamedParameterJdbcTemplate。
对于返回结果,可以直接使用List<Map<String, Object>>来接收,这也是个人比较推荐使用的方式,毕竟比较简单方便;也可以使用库表对应的实体对象来接收,不过这时候我们就需要手动创建一个实现了org.springframework.jdbc.core.RowMapper的对象,用于将实体对象属性和库表字段一一对应:
public class StudentMapper implements RowMapper<Student>{
@Override
public Student mapRow(ResultSet rs, int rowNum) throws SQLException {
Student student = new Student();
student.setSno(rs.getString("sno"));
student.setName(rs.getString("sname"));
student.setSex(rs.getString("ssex"));
return student;
}
}
测试
最终项目目录如下图所示:
启动项目,测试插入数据http://localhost:8080/web/addstudent?sno=004&name=Maria&sex=F:
查询所有学生数据http://localhost:8080/web/queryallstudent:
测试删除http://localhost:8080/web/deletestudent?sno=004: