pagehelper 分页不生效,总页数总是第一页解决方案

谁借莪１个温暖的怀抱￠ 2022-12-23 07:04 318阅读 0赞

说明:

PageHelper.startPage(pageNum,pageSize);只对该语句以后的第一个查询语句得到的数据进行分页。

### springboot坏境 ###

<dependency>
                <groupId>com.github.pagehelper</groupId>
                <artifactId>pagehelper</artifactId>
                <version>5.2.0</version>
            </dependency>
            <dependency>
                <groupId>com.github.pagehelper</groupId>
                <artifactId>pagehelper-spring-boot-autoconfigure</artifactId>
                <version>1.3.0</version>
            </dependency>
    
            <dependency>
                <groupId>com.github.pagehelper</groupId>
                <artifactId>pagehelper-spring-boot-starter</artifactId>
                <version>1.3.0</version>
            </dependency>

此方法会自动注入加载pagehelper插件

而不是原来的

<dependency>
        <groupId>com.github.pagehelper</groupId>
        <artifactId>pagehelper</artifactId>
        <version>{pagehelper.version}</version>
    </dependency>

因为上面的依赖缺少了

<dependency>
        <groupId>com.github.pagehelper</groupId>
        <artifactId>pagehelper-spring-boot-autoconfigure</artifactId>
    </dependency>

### 手动注入加载： ###

/**
     * @author zyc
     * @Description
     * @date 2019/10/25
     * @since v1.0.0
     */
    @Configuration
    @MapperScan(basePackages = TpDb.PACKAGE, sqlSessionFactoryRef = "testSqlSessionFactory")
    public class TpDb {
        protected static final String PACKAGE = "com.cy.test.dao.core.mysql.**.*";
        private static final String MAPPER_LOCATION = "classpath:mapper/**/*.xml";
        private Logger logger = LoggerFactory.getLogger(TpDb.class);
        @Value("${spring.datasource.url}")
        private String dbUrl;
    
        @Value("${spring.datasource.username}")
        private String username;
    
        @Value("${spring.datasource.password}")
        private String password;
    
        @Value("${spring.datasource.driverClassName:'com.mysql.jdbc.Driver'}")
        private String driverClassName;
    
        @Value("${spring.datasource.initialSize:30}")
        private int initialSize;
    
        @Value("${spring.datasource.minIdle:30}")
        private int minIdle;
    
        @Value("${spring.datasource.maxActive:150}")
        private int maxActive;
    
        @Value("${spring.datasource.maxWait:60000}")
        private int maxWait;
    
        @Value("${spring.datasource.timeBetweenEvictionRunsMillis:600000}")
        private int timeBetweenEvictionRunsMillis;
    
        @Value("${spring.datasource.minEvictableIdleTimeMillis:300000}")
        private int minEvictableIdleTimeMillis;
    
        @Value("${spring.datasource.validationQuery:'SELECT 1 FROM DUAL'}")
        private String validationQuery;
    
        @Value("${spring.datasource.testWhileIdle:false}")
        private boolean testWhileIdle;
    
        @Value("${spring.datasource.testOnBorrow:true}")
        private boolean testOnBorrow;
    
        @Value("${spring.datasource.testOnReturn:true}")
        private boolean testOnReturn;
    
        @Value("${spring.datasource.poolPreparedStatements:true}")
        private boolean poolPreparedStatements;
    
        @Value("${spring.datasource.maxPoolPreparedStatementPerConnectionSize:20}")
        private int maxPoolPreparedStatementPerConnectionSize;
    
        @Value("${spring.datasource.filters:log4j}")
        private String filters;
    
        @Value("${spring.datasource.connectionInitSqls}")
        private String connectionInitSqls;
    
        @Value("${spring.datasource.connectionProperties}")
        private String connectionProperties;
    
        @Bean(name = "testDataSource")
        @Primary
        public DataSource fkDataSource() {
            DruidDataSource dataSource = new DruidDataSource();
            dataSource.setDriverClassName(driverClassName);
            dataSource.setUrl(dbUrl);
            dataSource.setUsername(username);
            dataSource.setPassword(password);
            //configuration
            dataSource.setInitialSize(initialSize);
            dataSource.setMinIdle(minIdle);
            dataSource.setMaxActive(maxActive);
            dataSource.setMaxWait(maxWait);
            dataSource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);
            dataSource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
            dataSource.setValidationQuery(validationQuery);
            dataSource.setTestWhileIdle(testWhileIdle);
            dataSource.setTestOnBorrow(testOnBorrow);
            dataSource.setTestOnReturn(testOnReturn);
            dataSource.setPoolPreparedStatements(poolPreparedStatements);
            dataSource.setMaxPoolPreparedStatementPerConnectionSize(maxPoolPreparedStatementPerConnectionSize);
            StringTokenizer tokenizer = new StringTokenizer(connectionInitSqls, ";");
            //utf-8mb4
            dataSource.setConnectionInitSqls(Collections.list(tokenizer));
            try {
                dataSource.setFilters(filters);
            } catch (SQLException e) {
                logger.error("druid configuration initialization filter", e);
            }
            dataSource.setConnectionProperties(connectionProperties);
    
            try {
                dataSource.init();
            } catch (SQLException e) {
                logger.error("druid init error", e);
            }
            return dataSource;
        }
    
        @Bean(name = "testTransactionManager")
        @Primary
        public DataSourceTransactionManager fkTransactionManager() {
            return new DataSourceTransactionManager(fkDataSource());
        }
    
        @Bean(name = "testSqlSessionFactory")
        @Primary
        public SqlSessionFactory fkSqlSessionFactory(@Qualifier("testDataSource") DataSource fkDataSource)
            throws Exception {
            final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
            sessionFactory.setDataSource(fkDataSource);
            sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver()
                .getResources(TpDb.MAPPER_LOCATION));
    
            PageInterceptor pageInterceptor = new PageInterceptor();
            Properties properties = new Properties();
            properties.setProperty("reasonable", "false");
            properties.setProperty("helperDialect", "mysql");
            properties.setProperty("supportMethodsArguments", "true");
            properties.setProperty("returnPageInfo", "check");
            properties.setProperty("params", "count=countSql");
            pageInterceptor.setProperties(properties);
            // 添加插件
            sessionFactory.setPlugins(new Interceptor[] {pageInterceptor});
            return sessionFactory.getObject();
        }
    }

自定义数据源&加载分页加载

### 配置化： ###

mybatis-config.xml

<plugins>
            <plugin interceptor="com.github.pagehelper.PageInterceptor">
                <property name="helperDialect" value="mysql"></property>
                <property name="reasonable" value="true"></property>
            </plugin>
        </plugins>

示例：

public PageInfo<Order> findOrderList(int pageNum, int pageSize, OrderVO orderVO) {
            //使用分页插件,核心代码就这一行
            PageHelper.startPage(pageNum, pageSize);
     
            List<Order> list = orderMapper.findOrderList(orderVO);
            PageInfo<Order> pageInfo = new PageInfo<>(list);
            return pageInfo;
        }

参照：

[https://github.com/pagehelper/pagehelper-spring-boot][https_github.com_pagehelper_pagehelper-spring-boot]

[https://github.com/pagehelper/Mybatis-PageHelper/blob/master/wikis/zh/HowToUse.md][https_github.com_pagehelper_Mybatis-PageHelper_blob_master_wikis_zh_HowToUse.md]

[https://github.com/pagehelper/Mybatis-PageHelper][https_github.com_pagehelper_Mybatis-PageHelper]

[https_github.com_pagehelper_pagehelper-spring-boot]: https://github.com/pagehelper/pagehelper-spring-boot
[https_github.com_pagehelper_Mybatis-PageHelper_blob_master_wikis_zh_HowToUse.md]: https://github.com/pagehelper/Mybatis-PageHelper/blob/master/wikis/zh/HowToUse.md
[https_github.com_pagehelper_Mybatis-PageHelper]: https://github.com/pagehelper/Mybatis-PageHelper