在实际项目中涉及到多数据源和分表，所以采用了shardingsphere，为了简化代码，引入了mybatis plus
版本：
mybatis plus：3.3.2
springboot：2.1.5
shardingsphere ： 4.0.0-RC2
错误信息：
Caused by: org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException:
### Error querying database. Cause: java.lang.ClassCastException: java.lang.Long cannot be cast to java.lang.Integer
### The error may exist in com/cxm/db/mapper/bi/CxmBiDemoDAO.java (best guess)
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: SELECT id,increased_stall_count FROM cxm_bi_demo LIMIT ?,?
### Cause: java.lang.ClassCastException: java.lang.Long cannot be cast to java.lang.Integer
at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:92)
at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:440)
at com.sun.proxy.$Proxy150.selectList(Unknown Source)
at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:223)
at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.executeForIPage(MybatisMapperMethod.java:134)
at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.execute(MybatisMapperMethod.java:96)
at com.baomidou.mybatisplus.core.override.MybatisMapperProxy.invoke(MybatisMapperProxy.java:96)
at com.sun.proxy.$Proxy157.selectPage(Unknown Source)
at com.cxm.service.CxmBaseServiceImpl.page(CxmBaseServiceImpl.java:292)
at com.cxm.service.CxmBaseServiceImpl.page(CxmBaseServiceImpl.java:307)
at com.cxm.service.CxmBaseServiceImpl$$FastClassBySpringCGLIB$$5d9c5448.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:684)
at com.cxm.service.impl.CxmBiDemoServiceImpl$$EnhancerBySpringCGLIB$$e0e43073.page(<generated>)
at com.cxm.service.impl.CxmBiDailyIncreasedStatisticServiceImpl.queryIn(CxmBiDailyIncreasedStatisticServiceImpl.java:86)
at com.cxm.service.impl.CxmBiDailyIncreasedStatisticServiceImpl$$FastClassBySpringCGLIB$$588bac5b.invoke(<generated>)
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:749)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
at org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke(MethodBeforeAdviceInterceptor.java:56)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175)
at org.springframework.aop.aspectj.AspectJAfterAdvice.invoke(AspectJAfterAdvice.java:47)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:175)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:93)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:688)
at com.cxm.service.impl.CxmBiDailyIncreasedStatisticServiceImpl$$EnhancerBySpringCGLIB$$bbed46d4.queryIn(<generated>)
at com.cxm.CxmRetailApplication.run(CxmRetailApplication.java:68)
at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:813)
... 5 common frames omitted
Caused by: org.apache.ibatis.exceptions.PersistenceException:
### Error querying database. Cause: java.lang.ClassCastException: java.lang.Long cannot be cast to java.lang.Integer
### The error may exist in com/cxm/db/mapper/bi/CxmBiDemoDAO.java (best guess)
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: SELECT id,increased_stall_count FROM cxm_bi_demo LIMIT ?,?
### Cause: java.lang.ClassCastException: java.lang.Long cannot be cast to java.lang.Integer
at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:149)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:426)
... 32 common frames omitted
Caused by: java.lang.ClassCastException: java.lang.Long cannot be cast to java.lang.Integer
at org.apache.shardingsphere.core.optimize.sharding.segment.select.pagination.Pagination.getValue(Pagination.java:60)
at org.apache.shardingsphere.core.optimize.sharding.segment.select.pagination.Pagination.<init>(Pagination.java:54)
at org.apache.shardingsphere.core.optimize.sharding.segment.select.pagination.engine.LimitPaginationEngine.createPagination(LimitPaginationEngine.java:40)
at org.apache.shardingsphere.core.optimize.sharding.segment.select.pagination.engine.PaginationEngine.createPagination(PaginationEngine.java:50)
at org.apache.shardingsphere.core.optimize.sharding.engnie.dml.ShardingSelectOptimizeEngine.optimize(ShardingSelectOptimizeEngine.java:63)
at org.apache.shardingsphere.core.optimize.sharding.engnie.dml.ShardingSelectOptimizeEngine.optimize(ShardingSelectOptimizeEngine.java:47)
at org.apache.shardingsphere.core.route.router.sharding.ParsingSQLRouter.route(ParsingSQLRouter.java:72)
at org.apache.shardingsphere.core.route.PreparedStatementRoutingEngine.route(PreparedStatementRoutingEngine.java:66)
at org.apache.shardingsphere.core.PreparedQueryShardingEngine.route(PreparedQueryShardingEngine.java:60)
at org.apache.shardingsphere.core.BaseShardingEngine.executeRoute(BaseShardingEngine.java:86)
at org.apache.shardingsphere.core.BaseShardingEngine.shard(BaseShardingEngine.java:70)
at org.apache.shardingsphere.shardingjdbc.jdbc.core.statement.ShardingPreparedStatement.shard(ShardingPreparedStatement.java:224)
at org.apache.shardingsphere.shardingjdbc.jdbc.core.statement.ShardingPreparedStatement.execute(ShardingPreparedStatement.java:170)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.ibatis.logging.jdbc.PreparedStatementLogger.invoke(PreparedStatementLogger.java:59)
at com.sun.proxy.$Proxy227.execute(Unknown Source)
at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:64)
at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:63)
at com.sun.proxy.$Proxy226.query(Unknown Source)
at com.baomidou.mybatisplus.core.executor.MybatisSimpleExecutor.doQuery(MybatisSimpleExecutor.java:67)
at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:324)
at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
at com.baomidou.mybatisplus.core.executor.MybatisCachingExecutor.query(MybatisCachingExecutor.java:163)
at com.baomidou.mybatisplus.core.executor.MybatisCachingExecutor.query(MybatisCachingExecutor.java:90)
at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:147)
... 38 common frames omitted问题分析：
追踪日志，查看源码发现是由于shardingsphere的Pagination中有一个类型转换直接写死为int类型导致的，
因为分页参数里面穿的值是Long的类型，而下面这个方法直接强制转换为int，所以导致出错
private int getValue(final PaginationValueSegment paginationValueSegment, final List<Object> parameters) {
return paginationValueSegment instanceof ParameterMarkerPaginationValueSegment
? (int) parameters.get(((ParameterMarkerPaginationValueSegment) paginationValueSegment).getParameterIndex())
: ((NumberLiteralPaginationValueSegment) paginationValueSegment).getValue();
}因为mybatisplus的分页对象IPage里面的属性是long
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解决方案：
1：自定义实现com.baomidou.mybatisplus.core.metadata.IPage;，
将 private long size;private long current; 修改为int 类型可以修复这个问题，但没有进行覆盖测试，不知道是否会引起其他问题
2：重新shardingsphere的Pagination
3：弃用shardingsphere-core，分库分表采用阿里云的组建，多数据源采用AbstractRoutingDataSource自定义注解实现