mybatis pagehelper 插件

pagehelper 插件

pom.xml

<!--mybatis分页插件-->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>1.2.3</version>
        </dependency>

PageInterceptor 拦截器 实现Interceptor接口,拦截query方法

@SuppressWarnings({"rawtypes", "unchecked"})
@Intercepts(
    {
        @Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class}),
        @Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class, CacheKey.class, BoundSql.class}),
    }
)
public class PageInterceptor implements Interceptor {
    //缓存count查询的ms
    protected Cache<String, MappedStatement> msCountMap = null;
    private Dialect dialect;
    private String default_dialect_class = "com.github.pagehelper.PageHelper";
    private Field additionalParametersField;
    private String countSuffix = "_COUNT";

在调用查询之前,先调用select count 

pagehelper 的使用

1.调用静态方法startPage

2.执行查询方法

3.把查询的结果放在PageInfo 对象中

@Autowired
    private DeptMapper deptMapper;

    public PageInfo getAllDept(){
        PageHelper.startPage(1,10);
        List<Dept> deptList = deptMapper.selectAll();
        PageInfo pageInfo=new PageInfo(deptList);
        List<Dept> list = (List<Dept>)pageInfo.getList();
        for (Dept dept : list) {
            System.out.println("dept: "+dept);
        }
        System.out.println(pageInfo.getPageNum());
        System.out.println(pageInfo.getPageSize());
        System.out.println(pageInfo.getTotal());
        return pageInfo;
    }

https://blog.csdn.net/itcats_cn/article/details/81586724