在NES上,是否期望有多个“发现工作者”和“保持活着”线程处于等待状态?
"DiscoveryWorker-10"
Id=62 WAITING on java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@3c7f9371
at sun.misc.Unsafe.park(Native Method)
- waiting on java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@3c7f937
我知道这是一个非常基本的问题,但我被困在这里了,我不知道为什么。情况是这样的:我正在尝试连接我的Grails应用程序。我将.jar放在lib目录中,并将下面的代码放在BuildConfig.groovy中:
dependencies {
// specify dependencies here under either 'build', 'compile', 'runtime', 'test' or 'provided' scopes e.g.
// runtime 'mysql:mysq
有时我的glassfish服务器会在控制台中显示以下错误,你知道吗?
SEVERE: at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.signal(AbstractQueuedSynchronizer.java:1941)
SEVERE: at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1100)
SEVERE:
关闭executor时,我应该在哪里捕获RejectedExecutionExceptions?我试过了:
future {
Option(reader.readLine)
} onComplete {
case Success(v) =>
case Failure(e) => e match {
case ree: RejectedExecutionException =>
// doesn't work
}
和:
try {
futu
我想将"2018-04-13T20:00:00.0400“这样的DateTime字符串转换为”2018年4月13日“。我用了密码
val sdf = SimpleDateFormat("yyyy/mm/dd", Locale.getDefault())
val startDate = sdf.parse(data.start_time)
但是有了这段代码,我的应用程序就崩溃了。对此有任何帮助吗?
日志显示了
2018-10-11 16:44:56.948 20482-21021/? E/NowController: Failed to access data from
今天,我的java应用程序堆转储,我使用visualVM从服务器分析中复制转储文件,日志如下所示:
"WebSocketClient-SecureIO-1" daemon prio=5 tid=888 WAITING
at sun.misc.Unsafe.park(Native Method)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAn
我正在进行从Oracle到postgres的转换。我有以下问题:在Oracle Unpivot自动删除与空值,但postgres fails.How使Postgres一样甲骨文你能帮助我吗? Oracle: with detail as (
select
'A1' as a,
'A2' as b,
'A3' as c,
null as d
from dual