添加分页插件

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 1. pom文件添加依赖

<!-- https://mvnrepository.com/artifact/com.github.pagehelper/pagehelper -->
    <dependency>
      <groupId>com.github.pagehelper</groupId>
      <artifactId>pagehelper</artifactId>
      <version>4.2.1</version>
    </dependency>

2. mybatis-config文件配置

 <!-- 配置分页插件 -->
    <plugins>
        <plugin interceptor="com.github.pagehelper.PageHelper">
            <!-- 设置数据库类型 Oracle,Mysql,MariaDB,SQLite,Hsqldb,PostgreSQL六种数据库-->
            <property name="dialect" value="mysql"/>
        </plugin>
    </plugins>

3. 编写测试

   3.1 修改mapper class

public interface HelloMapper {

    public List<String> select() ;
}

  3.2 修改mapper xml

<select id="select" resultType="string">
        select text from tbl_test_hello
    </select>

  3.2 修改业务类

@Service
public class HelloService {

    @Autowired
    HelloMapper helloMapper ;

    public String getHelloString(int page){

        PageHelper.startPage(page,3) ;
        List<String> list = helloMapper.select();
        StringBuilder sb = new StringBuilder() ;
        for (int i = 0; i < list.size(); i++) {
            sb.append(list.get(i)) ;
            sb.append("<br>") ;
        }

        return sb.toString();
    }
}

  3.3 修改视图层

@Controller
public class HelloController {

    @Autowired
    HelloService helloService ;

    @ResponseBody
    @RequestMapping("/hello.do")
    public String testHello(@RequestParam(value = "page",defaultValue = "1") int page){
        return helloService.getHelloString(page) ;
    }

}

   3.4 测试结果