PageHelper插件

PageHelper.startPage(pn,5);  
//startPage后紧跟的这个查询就是分页查询  
List<Employee> emps = employeeService.getAll();  

@ConfigurationProperties(prefix = PageHelperProperties.PAGEHELPER_PREFIX)
public class PageHelperProperties {
public static final String PAGEHELPER_PREFIX = "pagehelper";

@Configuration
@ConditionalOnBean(SqlSessionFactory.class)
@EnableConfigurationProperties(PageHelperProperties.class)
@AutoConfigureAfter(MybatisAutoConfiguration.class)
public class PageHelperAutoConfiguration {
@Autowired
private List<SqlSessionFactory> sqlSessionFactoryList;
@Autowired
private PageHelperProperties properties;
/**
 * 接受分页插件额外的属性
 *
 * @return
 */
@Bean
@ConfigurationProperties(prefix = PageHelperProperties.PAGEHELPER_PREFIX)
public Properties pageHelperProperties() {
    return new Properties();
}
@PostConstruct
public void addPageInterceptor() {
    PageInterceptor interceptor = new PageInterceptor();
    Properties properties = new Properties();
    //先把一般方式配置的属性放进去
    properties.putAll(pageHelperProperties());
    //在把特殊配置放进去，由于close-conn 利用上面方式时，属性名就是 close-conn 而不是 closeConn，所以需要额外的一步
    properties.putAll(this.properties.getProperties());
    interceptor.setProperties(properties);
    for (SqlSessionFactory sqlSessionFactory : sqlSessionFactoryList) {
        sqlSessionFactory.getConfiguration().addInterceptor(interceptor);
    }
}

setLocalPage(page);
protected static final ThreadLocal<Page> LOCAL_PAGE = new ThreadLocal<Page>();

@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
  SqlSession sqlSession = getSqlSession(
      SqlSessionTemplate.this.sqlSessionFactory,
      SqlSessionTemplate.this.executorType,
      SqlSessionTemplate.this.exceptionTranslator);
  try {
    Object result = method.invoke(sqlSession, args);
    ..
    return result;
  } catch (Throwable t) {
    ..
  } finally {
    ..
  }
}