spring task 定时器执行一段时间就打印下面的错误日志，这个是什么问题，什么原因造成的，怎么解决？？
2019-11-05 09:42:07,090 WARN async.ThreadPoolAsynchronousRunner (ThreadPoolAsynchronousRunner.java:run:791) -com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@7c495b6f -- APPARENT DEADLOCK!!! Creating emergency threads for unassigned pending tasks!
2019-11-05 09:42:07,111 WARN async.ThreadPoolAsynchronousRunner (ThreadPoolAsynchronousRunner.java:run:807) -com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@7c495b6f -- APPARENT DEADLOCK!!! Complete Status:
Managed Threads: 3
Active Threads: 3
Active Tasks:
com.mchange.v2.c3p0.stmt.GooGooStatementCache$StatementDestructionManager$1UncheckedStatementCloseTask@67e99ca4
on thread: C3P0PooledConnectionPoolManager[identityToken->nb1w5dukzphi1cl6wf9|73d0af5e]-HelperThread-#2
com.mchange.v2.c3p0.stmt.GooGooStatementCache$StatementDestructionManager$1UncheckedStatementCloseTask@5f28f056
on thread: C3P0PooledConnectionPoolManager[identityToken->nb1w5dukzphi1cl6wf9|73d0af5e]-HelperThread-#1
com.mchange.v2.c3p0.stmt.GooGooStatementCache$StatementDestructionManager$1UncheckedStatementCloseTask@1d6d7b6b
on thread: C3P0PooledConnectionPoolManager[identityToken->nb1w5dukzphi1cl6wf9|73d0af5e]-HelperThread-#0
Pending Tasks:
com.mchange.v2.resourcepool.BasicResourcePool$1RefurbishCheckinResourceTask@7b9e8845
com.mchange.v2.resourcepool.BasicResourcePool$1RefurbishCheckinResourceTask@5039372e
com.mchange.v2.resourcepool.BasicResourcePool$1RefurbishCheckinResourceTask@480bc73f
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@3e4b5b76
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@3118305a
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@2881f110
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@3ea5f900
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@5ad18549
com.mchange.v2.resourcepool.BasicResourcePool$AsyncTestIdleResourceTask@2abbe4a9
com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask@d95999f
com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask@1ce90cd4
com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask@4a4439cd
com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask@3f2f0280
com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask@1ed72d9b
com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask@4a0c0d39
Pool thread stack traces:
Thread[C3P0PooledConnectionPoolManager[identityToken->nb1w5dukzphi1cl6wf9|73d0af5e]-HelperThread-#2,5,main]
oracle.jdbc.driver.OracleStatement.close(OracleStatement.java:1343)
oracle.jdbc.driver.OracleStatementWrapper.close(OracleStatementWrapper.java:100)
oracle.jdbc.driver.OraclePreparedStatementWrapper.close(OraclePreparedStatementWrapper.java:82)
com.mchange.v1.db.sql.StatementUtils.attemptClose(StatementUtils.java:53)
com.mchange.v2.c3p0.stmt.GooGooStatementCache$StatementDestructionManager$1UncheckedStatementCloseTask.run(GooGooStatementCache.java:934)
com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:696)
Thread[C3P0PooledConnectionPoolManager[identityToken->nb1w5dukzphi1cl6wf9|73d0af5e]-HelperThread-#1,5,main]
oracle.jdbc.driver.OracleStatement.close(OracleStatement.java:1343)
oracle.jdbc.driver.OracleStatementWrapper.close(OracleStatementWrapper.java:100)
oracle.jdbc.driver.OraclePreparedStatementWrapper.close(OraclePreparedStatementWrapper.java:82)
com.mchange.v1.db.sql.StatementUtils.attemptClose(StatementUtils.java:53)
com.mchange.v2.c3p0.stmt.GooGooStatementCache$StatementDestructionManager$1UncheckedStatementCloseTask.run(GooGooStatementCache.java:934)
com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:696)
Thread[C3P0PooledConnectionPoolManager[identityToken->nb1w5dukzphi1cl6wf9|73d0af5e]-HelperThread-#0,5,main]
oracle.jdbc.driver.OracleStatement.close(OracleStatement.java:1343)
oracle.jdbc.driver.OracleStatementWrapper.close(OracleStatementWrapper.java:100)
oracle.jdbc.driver.OraclePreparedStatementWrapper.close(OraclePreparedStatementWrapper.java:82)
com.mchange.v1.db.sql.StatementUtils.attemptClose(StatementUtils.java:53)
com.mchange.v2.c3p0.stmt.GooGooStatementCache$StatementDestructionManager$1UncheckedStatementCloseTask.run(GooGooStatementCache.java:934)
com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:696)
