@Component
@Mapper
public interface StudentMapper {
@Insert("INSERT INTO student (name, sex, addr) VALUES (#{name}, #{sex}, #{addr})")
int insert(Student stu);
@InsertProvider(type = Provider.class, method = "batchInsert")
int batchInsert(List<Student> students);
@Select("SELECT * FROM student WHERE id = #{id}")
Student selectById(@Param("id") int id);
@DeleteProvider(type = Provider.class, method = "batchDelete")
int batchDelete(List<Student> students);
@Select("SELECT * FROM student")
List<Student> selectAll();
class Provider {
/* 批量插入 */
public String batchInsert(Map map) {
List<Student> students = (List<Student>) map.get("list");
StringBuilder sb = new StringBuilder();
sb.append("INSERT INTO student (name,sex,addr) VALUES ");
MessageFormat mf = new MessageFormat(
"(#'{'list[{0}].name}, #'{'list[{0}].sex}, #'{'list[{0}].addr})"
);
for (int i = 0; i < students.size(); i++) {
sb.append(mf.format(new Object[] {i}));
if (i < students.size() - 1)
sb.append(",");
}
return sb.toString();
}
/* 批量删除 */
public String batchDelete(Map map) {
List<Student> students = (List<Student>) map.get("list");
StringBuilder sb = new StringBuilder();
sb.append("DELETE FROM student WHERE id IN (");
for (int i = 0; i < students.size(); i++) {
sb.append("'").append(students.get(i).getId()).append("'");
if (i < students.size() - 1)
sb.append(",");
}
sb.append(")");
return sb.toString();
}
}
}