I believe Andrew is right , fixing this problem based on jvm vendor
names is likely to be error prone and endorsing particular jvm's is
not good.
After Looking at the code catching FileNotFoundException when log
file is opened "rws" mode does not seem to need major
changes in the code.
Problem : unable to create db on MAC because when log files are opened
in write sync mode on MAC JVM 1.4.2 , FileNotFoundException occurs.
Possible Fix : Catch the FileNotFoundException then set log write mode
to file Sync and open the log files in plain "rw" mode.
Thanks
-suresh
Index: java/engine/org/apache/derby/impl/store/raw/log/LogToFile.java
===================================================================
--- java/engine/org/apache/derby/impl/store/raw/log/LogToFile.java
(revision 54756)
+++ java/engine/org/apache/derby/impl/store/raw/log/LogToFile.java
(working copy)
@@ -80,6 +80,7 @@
import java.io.File; // Plain files are used for backups
import java.io.IOException;
import java.io.SyncFailedException;
+import java.io.FileNotFoundException;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.ByteArrayInputStream;
@@ -895,7 +896,7 @@
//extend the file by
wring zeros to it
preAllocateNewLogFile(theLog);
theLog.close();
- theLog=
privRandomAccessFile(logFile, "rws");
+ theLog =
openLogFileInWriteMode(logFile);
//postion the log at
the current end postion
theLog.seek(endPosition);
}
@@ -931,7 +932,7 @@
try
{
if(isWriteSynced)
- theLog =
privRandomAccessFile(logFile, "rws");
+ theLog =
openLogFileInWriteMode(logFile);
else
theLog =
privRandomAccessFile(logFile, "rw");
}
@@ -1930,7 +1931,7 @@
//extend the file by wring
zeros to it
preAllocateNewLogFile(newLog);
newLog.close();
- newLog=
privRandomAccessFile(newLogFile, "rws");
+ newLog =
openLogFileInWriteMode(newLogFile);
newLog.seek(endPosition);
}
@@ -3020,7 +3021,7 @@
//extend the file by wring zeros to it
preAllocateNewLogFile(theLog);
theLog.close();
- theLog= privRandomAccessFile(logFile, "rws");
+ theLog = openLogFileInWriteMode(logFile);
//postion the log at the current log end postion
theLog.seek(endPosition);
}
@@ -4846,15 +4847,34 @@
}
} // end of preAllocateNewLogFile
- /*open the given log file name for writes; if write sync
- *is enabled open in rws mode otherwise in rw mode.
+
+
+ /**
+ * open the given log file name for writes; if file can not be
+ * be opened in write sync mode then disable the write sync mode and
+ * open the file in "rw" mode.
*/
- public StorageRandomAccessFile openLogFileInWriteMode(StorageFile
logFile) throws IOException
+ private StorageRandomAccessFile openLogFileInWriteMode(StorageFile
logFile) throws IOException
{
- if(isWriteSynced)
- return privRandomAccessFile(logFile, "rws");
- else
- return privRandomAccessFile(logFile, "rw");
+
+ StorageRandomAccessFile log;
+ try{
+ log = privRandomAccessFile(logFile, "rws");
+ }catch(FileNotFoundException ex)
+ {
+ // Normally this exception should never occur. For some
reason
+ // currently on Mac JVM 1.4.2 FileNotFoundException
exception is
+ // thrown if a file is opened in "rws" mode and if it
already
+ // exists. Please refere to Derby-1 for more/ details
on this issue.
+ // Temporary workaround to avoid this problem is to
make the logging
+ // system use file sync mechanism.
+
+ // disable the write sync and open the file in "rw"
mode.
+ isWriteSynced = false;
+ log = privRandomAccessFile(logFile, "rw");
+ }
+
+ return log ;
}
