小编chu*_*hun的帖子

我有一个Linux bash脚本'myshell'.我希望它读取两个日期作为参数,例如:myshell date1 date2.我是一名Java程序员,但不知道如何编写脚本来完成这项工作.

脚本的其余部分是这样的:

sed "s/$date1/$date2/g" wlacd_stat.xml >tmp.xml
mv tmp.xml wlacd_stat.xml

谁能告诉我为什么这个类的输出是'xa'？

为什么不会捕获其他异常(RuntimeException和Exception)？

public class Tree {
    public static void main(String... args) {
        try
        {
            throw new NullPointerException(new Exception().toString());
        }
        catch (NullPointerException e)
        {
            System.out.print("x");
        }
        catch (RuntimeException e)
        {
            System.out.print("y");
        }
        catch (Exception e)
        {
            System.out.print("z");   
        }        
        finally{System.out.println("a");}
    }
}

我使用的报告工具只支持一行表达式

举个例子,我想得到昨天的日期

Calendar类有一个add方法,但它返回void

Calendar.getInstance().add(Calendar.DAY_OF_MONTH,-1).getTime()

没用

不知道怎么做到这一点

谢谢

这是一个来自java考试的问题,

在#1有多少个物品可以进行gabage收集？

public class Main   {

Integer x = 32768;
public static void main(String[] args)
{ 
    Main m = new Main();
    m = null;
    // #1
  } 
}

我以为它只收集整数x,GC甚至收集主要对象m？

public static void main(String[] args)
{
    int [][]shatner = new int[1][1];
    int []rat = new int[4];
    shatner[0] = rat;
    System.out.println(shatner[0][3]);
}    

惊讶,输出为0,为什么Java不检查这种indexOutOfBound错误？

我们遇到了一个问题,如下所示,我们不知道问题是:1.从数据库读取的时间太短到达StuckThreadMaxTime 600s 2.database查询运行时间过长2.锁定数据库或其他对象

任何建议将不胜感激!

螺纹-36 "[STUCK] ExecuteThread: '3' 的队列: 'weblogic.kernel.Default(自调谐)'"{jrockit.net.SocketNativeIO.readBytesPinned(SocketNativeIO.java:???)jrockit.net.SocketNativeIO .socketRead(SocketNativeIO.java:31)java.net.SocketInputStream.socketRead0(SocketInputStream.java:???)java.net.SocketInputStream.read(SocketInputStream.java:107)com.microsoft.sqlserver.jdbc.DBComms.receive (未知来源)com.microsoft.sqlserver.jdbc.SQLServerStatement.doExecuteStatement(未知来源)com.microsoft.sqlserver.jdbc.SQLServerStatement $ StatementExecutionRequest.executeStatement(未知来源)com.microsoft.sqlserver.jdbc.CancelableRequest.execute(未知来源) )com.microsoft.sqlserver.jdbc.SQLServerConnection.executeRequest(未知来源)

^ - 持有锁:com.microsoft.sqlserver.jdbc.TDSWriter@41dbbdd [瘦锁] com.microsoft.sqlserver.jdbc.SQLServerStatement.executeQuery(未知来源)com.microsoft.sqlserver.jdbc.SQLServerStatement.getMaxFieldSize(未知来源) )weblogic.jdbc.common.internal.ConnectionEnv.cleanUpStatementForReUse(ConnectionEnv.java:1356)weblogic.jdbc.common.internal.ConnectionEnv.returnCachedStatement(ConnectionEnv.java:1118) ^ - 持有锁:weblogic.jdbc.common.internal .ConnectionEnv $ -1 @ 41f2d97 [瘦锁] weblogic.jdbc.wrapper.Statement.internalClose(Statement.java:342)weblogic.jdbc.wrapper.Statement.doClose(Statement.java:399)weblogic.jdbc.wrapper.Statement.close (Statement.java:391)com.riskintegrator.infrastructure.database.DBConnector.getConnection(DBConnector.java:66)^ - 持有锁:com.riskintegrator.infrastructure.database.DBConnector@1fda7d8 [瘦锁] com.riskintegrator. infrastructure.database.DBConnector.(DBConnector.java:56)com.riskintegrator.slsb.BaseSessionBean.populateFormWith PreparedStatement的(BaseSessionBean.java:76)com.riskintegrator.slsb.BaseSession_6uq9n4_EOImpl.populateFormWithPreparedStatement(BaseSession_6uq9n4_EOImpl.java:763)com.riskintegrator.slsb.BaseSessionDelegate.populateFormWithPreparedStatement(BaseSessionDelegate.java:118)com.riskintegrator.slsb.setup.SeverityBandBD. selectByValue(SeverityBandBD.java:181)com.riskintegrator.slsb.ca.ComputeAssessmentScoreBean.ComputeRiskScore(ComputeAssessmentScoreBean.java:332)com.riskintegrator.slsb.ca.ComputeAssessmentScoreBean.ComputeAssessmentScore(ComputeAssessmentScoreBean.java:119)com.riskintegrator.slsb. ca.ComputeAssessmentScoreBean_s478gq_EOImpl.ComputeAssessmentScore(ComputeAssessmentScoreBean_s478gq_EOImpl.java:37)com.riskintegrator.slsb.ca.ComputeAssessmentScoreBD.ComputeAssessmentScore(ComputeAssessmentScoreBD.java:32)com.riskintegrator.slsb.ca.AssessmentScoreBean.ProcessAssessment(AssessmentScoreBean.java:44)com. riskintegrator.slsb.ca.AssessmentScoreSession_nlmr0a_EOImpl.ProcessAssessme nt(AssessmentScoreSession_nlmr0a_EOImpl.java:37)com.riskintegrator.slsb.ca.AssessmentScoreBD.ProcessAssessment(AssessmentScoreBD.java:36)com.riskintegrator.slsb.ScheduledBatchBean.executeJob(ScheduledBatchBean.java:568)com.riskintegrator.slsb.ScheduledBatchBean. executeDailyRunOnce(ScheduledBatchBean.java:792)com.riskintegrator.slsb.ScheduledBatchBean.ejbTimeout(ScheduledBatchBean.java:957)weblogic.ejb.container.timer.TimerImpl.timerExpired(TimerImpl.java:219)

^ - 持有锁:weblogic.ejb.container.timer.TimerImpl@12c8e34 [瘦锁] weblogic.timers.internal.TimerImpl.run(TimerImpl.java:253)weblogic.work.SelfTuningWorkManagerImpl $ WorkAdapterImpl.run(SelfTuningWorkManagerImpl.java :516)weblogic.work.ExecuteThread.execute(ExecuteThread.java:198)weblogic.work.ExecuteThread.run(ExecuteThread.java:165)