Good advice -- always be on the lookout for cleanup that can be done
in a finally, even if you don't see it as strictly necessary!
Actually, you can usually simplify this slightly:
Cursor c = ...;
try {
dostuff(c); // Do something with the cursor
} finally {
c.close();
}
There's no timing window or anything here. The variable 'c' won't be
assigned unless there's a successful return of a cursor, and there's
no opportunity for a throw between that and the operations on the
cursor.
Separating the assignment and moving it into the try body does require
that you test for null in the finally clause. Occasionally it's worth
the extra hassle, so you can combine the finally with another try/
catch -- but usually it's better to simply use a separate try/catch
for each. In C++, assignments can generate exceptions, so doing the
assignment within the try is a good habit, and sometimes essential. In
Java, this is not a concern, so we can optimize for making it as easy
as possible to write and read the code, and thus encouraging liberal
use of the pattern!
BTW, try/catch are not expensive in the non-throw case. It generates
static code ranges that are looked up during handling throw, and
doesn't involve any extra execution steps if no throw is done. So
always just try for the cleanest code.
On Feb 8, 10:12 am, Jason Proctor <jason.android.li...@gmail.com>
wrote:
> well, like the error says, the cursor is being garbage collected but
> it hadn't been closed or deactivated.
>
> you must close your cursors!
>
> and do it in a finally block so that they still get closed even if
> other code throws an exception.
>
> for example --
>
> Cursor c = null;
>
> try
> {
> c = resolver.query (...);
>
> // ...run through the query}
>
> finally
> {
> if (c != null)
> {
> c.close ();
> }
>
> }
>
> not exactly like this, but you get the idea.
>
> hth
> J
>
>
>
>
>
> >Hi,
>
> >In my program i'm using sqlite database.
>
> >After using that Sqlite program when i'm using some other layout it
> >is showing the below exception.
>
> >02-06 14:17:59.320: INFO/dalvikvm(853): Uncaught exception thrown by
> >finalizer (will be discarded):
> >02-06 14:17:59.371: INFO/dalvikvm(853):
> >Ljava/lang/IllegalStateException;: Finalizing cursor
> >android.database.sqlite.sqlitecur...@43c4e358 on DB1 that has not
> >been deactivated or closed
> >02-06 14:17:59.729: INFO/dalvikvm(853): at
> >android.database.sqlite.SQLiteCursor.finalize(SQLiteCursor.java:596)
> >02-06 14:17:59.800: INFO/dalvikvm(853): at
> >dalvik.system.NativeStart.run(Native Method)
> >02-06 14:17:59.878: INFO/dalvikvm(853): Uncaught exception thrown by
> >finalizer (will be discarded):
> >02-06 14:17:59.900: INFO/dalvikvm(853):
> >Ljava/lang/IllegalStateException;: Finalizing cursor
> >android.database.sqlite.sqlitecur...@43b9cf30 on DB2 that has not
> >been deactivated or closed
> >02-06 14:17:59.909: INFO/dalvikvm(853): at
> >android.database.sqlite.SQLiteCursor.finalize(SQLiteCursor.java:596)
> >02-06 14:17:59.919: INFO/dalvikvm(853): at
> >dalvik.system.NativeStart.run(Native Method)
> >02-06 14:17:59.968: INFO/dalvikvm(853): Uncaught exception thrown by
> >finalizer (will be discarded):
> >02-06 14:17:59.989: INFO/dalvikvm(853):
> >Ljava/lang/IllegalStateException;: Finalizing cursor
> >android.database.sqlite.sqlitecur...@43b9c5e8 on null that has not
> >been deactivated or closed
> >02-06 14:18:00.049: INFO/dalvikvm(853): at
> >android.database.sqlite.SQLiteCursor.finalize(SQLiteCursor.java:596)
> >02-06 14:18:00.049: INFO/dalvikvm(853): at
> >dalvik.system.NativeStart.run(Native Method)
> >02-06 14:18:00.088: INFO/dalvikvm(853): Uncaught exception thrown by
> >finalizer (will be discarded):
> >02-06 14:18:00.109: INFO/dalvikvm(853):
> >Ljava/lang/IllegalStateException;: Finalizing cursor
> >android.database.sqlite.sqlitecur...@43b95fc8 on null that has not
> >been deactivated or closed
> >02-06 14:18:00.119: INFO/dalvikvm(853): at
> >android.database.sqlite.SQLiteCursor.finalize(SQLiteCursor.java:596)
> >02-06 14:18:00.140: INFO/dalvikvm(853): at
> >dalvik.system.NativeStart.run(Native Method)
>
> >wat's this?..
> >how to over come this?
> >any one can explain me?..
>
> >--
> >Thanks & Regards
> >Sasikumar.S
>
> >--
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>
> --
> jason.vp.engineering.particle
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