Druid数据库连接池异常--求助问题贴

1.异常问题描述：

项目重启运行一段时间之后(几个小时甚至几天)，会抛获取连接异常(异常日志这种下面)，但又不影响数据库的访问，项目能正常运行，数据库数据能正常获取。

2.异常日志信息：

2019-02-18 11:42:43.789 WARN 30571 --- [uire-timer-jobs] com.alibaba.druid.pool.DruidDataSource : get connection timeout retry : 1
2019-02-18 11:43:43.791 ERROR 30571 --- [uire-timer-jobs] o.f.j.s.i.a.AcquireTimerJobsRunnable : exception during timer job acquisition: Could not open JDBC Connection for transaction; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 60001, active 1, maxActive 21, creating 1

org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for transaction; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 60001, active 1, maxActive 21, creating 1
   at org.springframework.jdbc.datasource.DataSourceTransactionManager.doBegin(DataSourceTransactionManager.java:289)
   at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373)
   at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:130)
   at org.flowable.spring.SpringTransactionInterceptor.execute(SpringTransactionInterceptor.java:46)
   at org.flowable.engine.common.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:30)
   at org.flowable.engine.common.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:56)
   at org.flowable.engine.common.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:51)
   at org.flowable.job.service.impl.asyncexecutor.AcquireTimerJobsRunnable.run(AcquireTimerJobsRunnable.java:58)
   at java.lang.Thread.run(Thread.java:748)
Caused by: com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 60001, active 1, maxActive 21, creating 1
   at com.alibaba.druid.pool.DruidDataSource.getConnectionInternal(DruidDataSource.java:1504)
   at com.alibaba.druid.pool.DruidDataSource.getConnectionDirect(DruidDataSource.java:1247)
   at com.alibaba.druid.filter.FilterChainImpl.dataSource_connect(FilterChainImpl.java:4619)
   at com.alibaba.druid.filter.stat.StatFilter.dataSource_getConnection(StatFilter.java:680)
   at com.alibaba.druid.filter.FilterChainImpl.dataSource_connect(FilterChainImpl.java:4615)
   at com.alibaba.druid.filter.FilterAdapter.dataSource_getConnection(FilterAdapter.java:2745)
   at com.alibaba.druid.filter.FilterChainImpl.dataSource_connect(FilterChainImpl.java:4615)
   at com.alibaba.druid.filter.logging.LogFilter.dataSource_getConnection(LogFilter.java:876)
   at com.alibaba.druid.filter.FilterChainImpl.dataSource_connect(FilterChainImpl.java:4615)
   at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1225)
   at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1217)
   at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:90)
   at sun.reflect.GeneratedMethodAccessor179.invoke(Unknown Source)
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
   at java.lang.reflect.Method.invoke(Method.java:498)
   at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:333)
   at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)
   at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
   at com.alibaba.druid.support.spring.stat.DruidStatInterceptor.invoke(DruidStatInterceptor.java:72)
   at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
   at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)
   at com.sun.proxy.$Proxy245.getConnection(Unknown Source)
   at org.springframework.jdbc.datasource.DataSourceTransactionManager.doBegin(DataSourceTransactionManager.java:246)
   ... 8 common frames omitted

3.Druid连接池配置信息：

private String driverClassName = "com.mysql.jdbc.Driver";
   private Integer initialSize = 2;
   private Integer minIdle = 1;
   private Integer maxActive = 21;
   private Integer maxWait = 60001;
   private Integer timeBetweenEvictionRunsMillis = 60000;
   private Integer minEvictableIdleTimeMillis = 300000;
   private String validationQuery = "SELECT 'x'";
   private Boolean testWhileIdle = true;
   private Boolean testOnBorrow = false;
   private Boolean testOnReturn = false;
   private Boolean poolPreparedStatements = true;
   private Integer maxPoolPreparedStatementPerConnectionSize = 20;
   private String filters = "stat";
   private Boolean removeAbandoned = true;
   private Integer removeAbandonedTimeout = 300;
   private Boolean logAbandoned = true;

不知道怎么修改才能解决这个问题，希望大神们给看看！！！