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  1. JDK
  2. JDK-4761344

NullPointerException just before data loss

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    • Subcomponent:
    • Resolved In Build:
      03
    • CPU:
      generic, sparc
    • OS:
      generic, solaris_8

      Backports

        Description

        ===============================================
        09/10/2002 11:17:47
        ===============================================
        java version "1.4.1"
        Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1-b21)
        Java HotSpot(TM) 64-Bit Server VM (build 1.4.1_01-b01, mixed mode)

        com.adventnet.snmp.snmp2.agent.AgentRuntimeException: Failure in opening SnmpSession, errstat: 0, errvalue: 0

        at com.adventnet.snmp.snmp2.agent.SnmpAgent.addClientAndOpenSession(SnmpAgent.java:801)
        at com.adventnet.snmp.snmp2.agent.SnmpAgent.restartSnmpAgent(SnmpAgent.java:939)
        at com.adventnet.snmp.snmp2.agent.SnmpAgent.restartSnmpAgent(SnmpAgent.java:955)
        at com.adventnet.snmp.snmp2.agent.SnmpAgent.setPort(SnmpAgent.java:1034)
        at com.xacct.xacctusage.util.xmi.snmpagent.XacctUsage.initXacctUsage(XacctUsage.java:250)
        at com.xacct.xacctusage.util.xmi.snmpagent.XacctUsage.init(XacctUsage.java:320)
        at com.xacct.xacctusage.core.Application$1.run(Application.java:897)
        at java.lang.Thread.run(Thread.java:536)
        CSVLogReader.CreateMapArguments() - Exception !!!
        java.lang.NullPointerException

        All files mentioned in the description are in the attachments

        Problem description :
        ------------------------------

        We have CSVLogReader.class that performs CSV file line parsing . After
        reading the line from the file, the CreateMapArguments(String line)
        method is called in order to put each field to the buffer according to its
        type. Inside this method there is a try/catch (Exception E) block, that
        sometimes
        catches NullPointerException. In order to understand the reason, we've
        inserted E.printStackTrace() call, and we've expected to see the stack trace
        for this
        Exception object in the standard output. But only
        "java.lang.NullPointerException" was printed. So the first question is: why
        we didn't see the full stack trace ?
        Using
                        Throwable X = E.fillInStackTrace();
                        X.printStackTrace();
        gives the same results.

        Then we've concluded that the only way to see what object caused the
        NullPointerException is to produce a thread dump immediately after catching
        the exception.
        From the program we called to a script that sent kill -QUIT signal to the
        process. The results of the thread point that the source of this Exception
        is inside Java classes.

        Examples
        ---------------

        Here are some examples from several thread dumps that show the threads which
        called to the CreateMapArguments() method:

        1. Thread dump from gath7_stdout.log

        "Thread-24" prio=5 tid=0x1053d0680 nid=0x4a runnable
        [fffffffec7a00000..fffffffec7a014a0]
        at
        ISM.ISM_114_1_0.CSVFieldTokenizer.fieldAsString(CSVFieldTokenizer.java:161)
        at ISM.ISM_114_1_0.CSVLogReader.CreateMapArguments(CSVLogReader.java:426)
        at ISM.ISM_114_1_0.CSVLogReader.processRecord(CSVLogReader.java:333)
        at ISM.ISM_114_1_0.LogReader.readNewLines(LogReader.java:575)
        at ISM.ISM_114_1_0.LogReader.run(LogReader.java:484)
        - locked <fffffffee8b85858> (a ISM.ISM_114_1_0.CSVLogReader)

        Here is the ISM.ISM_114_1_0.CSVFieldTokenizer.fieldAsString() method with
        line 161 specified:

            public String fieldAsString(int FieldNo)
            {
                char[] arr = new char[m_FieldLen[FieldNo]]; // line 161
                System.arraycopy(m_Buffer[FieldNo], 0, arr, 0, m_FieldLen[FieldNo]);
                return (new String(arr));
            }

        As you can see, no our objects were called in this line.

        The same situation we can see in the gath9_stdout.log :

        "Thread-15" prio=5 tid=0x1055f2180 nid=0x30 runnable
        [fffffffecae00000..fffffffecae014a0]
        at
        ISM.ISM_114_1_0.CSVFieldTokenizer.fieldAsString(CSVFieldTokenizer.java:161)
        at ISM.ISM_114_1_0.CSVLogReader.CreateMapArguments(CSVLogReader.java:426)
        at ISM.ISM_114_1_0.CSVLogReader.processRecord(CSVLogReader.java:333)
        at ISM.ISM_114_1_0.LogReader.readNewLines(LogReader.java:575)
        at ISM.ISM_114_1_0.LogReader.run(LogReader.java:484)
        - locked <fffffffee8b86ef8> (a ISM.ISM_114_1_0.CSVLogReader)

        2. Thread dump from gath17_stdout.log

        "Thread-26" prio=5 tid=0x1002eb170 nid=0x53 runnable
        [fffffffec6600000..fffffffec66014a0]
        at java.lang.Integer.intValue(Integer.java:591)
        at Util.MapArguments.putString(MapArguments.java:889)
        at ISM.ISM_114_1_0.CSVLogReader.CreateMapArguments(CSVLogReader.java:426)
        at ISM.ISM_114_1_0.CSVLogReader.processRecord(CSVLogReader.java:333)
        at ISM.ISM_114_1_0.LogReader.readNewLines(LogReader.java:575)
        at ISM.ISM_114_1_0.LogReader.run(LogReader.java:484)
        - locked <fffffffee8b85070> (a ISM.ISM_114_1_0.CSVLogReader)

        Here is the Util.MapArguments.putString() method with line 889 specified:

            public void putString(Integer Key, String Value)
            {
        putString(Key.intValue(), Value); // line 889
            }

        As you can see, the Integer.intValue() method is called before Exception was
        thrown.

        3. Thread dump from gath20_stdout.log

        "Thread-24" prio=5 tid=0x100301430 nid=0x44 runnable
        [fffffffec8400000..fffffffec84014a0]
        at java.util.Calendar.complete(Calendar.java:1095)
        at java.util.Calendar.get(Calendar.java:942)
        at ISM.ISM_114_1_0.SuperParser.parseDateTime(SuperParser.java:286)
        at ISM.ISM_114_1_0.CSVLogReader.CreateMapArguments(CSVLogReader.java:476)
        at ISM.ISM_114_1_0.CSVLogReader.processRecord(CSVLogReader.java:333)
        at ISM.ISM_114_1_0.LogReader.readNewLines(LogReader.java:575)
        at ISM.ISM_114_1_0.LogReader.run(LogReader.java:484)
        - locked <fffffffee81867c8> (a ISM.ISM_114_1_0.CSVLogReader)

        The relevant line in the ISM.ISM_114_1_0.SuperParser.parseDateTime() is :
                int Year = m_CalObj.get(Calendar.YEAR); // line 286

        The same situation we can see in the gath24_stdout.log :

        "Thread-23" prio=5 tid=0x1002fa8e0 nid=0x43 runnable
        [fffffffec8500000..fffffffec85014a0]
        at java.util.Calendar.get(Calendar.java:943)
        at ISM.ISM_114_1_0.SuperParser.parseDateTime(SuperParser.java:286)
        at ISM.ISM_114_1_0.CSVLogReader.CreateMapArguments(CSVLogReader.java:476)
        at ISM.ISM_114_1_0.CSVLogReader.processRecord(CSVLogReader.java:333)
        at ISM.ISM_114_1_0.LogReader.readNewLines(LogReader.java:575)
        at ISM.ISM_114_1_0.LogReader.run(LogReader.java:484)
        - locked <fffffffee8181e08> (a ISM.ISM_114_1_0.CSVLogReader)

        As you can see, the Calendar m_CalObj method is not null here, and the
        problem is in the Calendar methods.

        4. Thread dump from gath28_stdout.log

        "Thread-30" prio=5 tid=0x105562140 nid=0x52 runnable
        [fffffffec6f00000..fffffffec6f014a0]
        at Util.MapArguments.putString(MapArguments.java:903)
        at Util.MapArguments.putString(MapArguments.java:889)
        at ISM.ISM_114_1_0.CSVLogReader.CreateMapArguments(CSVLogReader.java:426)
        at ISM.ISM_114_1_0.CSVLogReader.processRecord(CSVLogReader.java:333)
        at ISM.ISM_114_1_0.LogReader.readNewLines(LogReader.java:575)
        at ISM.ISM_114_1_0.LogReader.run(LogReader.java:484)
        - locked <fffffffee8b814a0> (a ISM.ISM_114_1_0.CSVLogReader)

        The relevant line in the Util.MapArguments.putString() is :
                     m_StringErr [KeyDesc.Index] = NO_ERROR; // line 903

        The m_StringErr is a array of booleans.

        How do you explain this situation ? What object can cause the
        NullPointerException ? And why we can't see the stack trace
        by using printStackTrace() call ?

        Attached with this email :
        1. All mentioned thread dumps (gath7_stdout.log, gath9_stdout.log,
        gath17_stdout.log, gath20_stdout.log, gath24_stdout.log, gath28_stdout.log)
        .
        2. The CSVLogReader source file.

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                Assignee:
                jrose John Rose
                Reporter:
                atongschsunw Albert Tong-schmidt (Inactive)
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                  Updated:
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