Thread

[Keystone Slip # 15] JDBC getTimestamp() aborts with some Locales

webmaster@postgresql.org — 1999-07-26T16:41:21Z

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Slip number -----: 15
Problem ---------: JDBC getTimestamp() aborts with some Locales
Opened by -------: rcoelho@px.com.br on 07/25/99 10:02
Assigned To -----: scrappy
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Summary:
--------- Plataform Description
RedHat Linux 5.2 Intel
Postgresql 6.5
Blackdown Java 1.1.7
-------------- Simple description
If your locale is not supported by Java standard, SimpleDateFormat(in getTimestamp function)can't parse timezone ID. This problem has solution but the exception error messages is really strange.
------------------- To reproduce the problem
# first set RHLinux Timezone to EST with /usr/sbin/timeconfig. I'm using Brazil/East

export LANG=pt_BR       # Portuguese (Brazil)
psql mydb
mydb> create table timetest(anyfield timestamp);
mydb> insert into timetest values (now());
mydb> q
java example.psql jdbc:postgresql.....       # from pgsql/src/interfaces/jdbc

# The program will abort with error in MessageFormat. See in explanation.
--------------- Partial Solution
SimpleDateFormat support PGSql syntax for string timestamp's timezone (GMT offset, in my case -03).
I just cut the offset conversion to timezone ID in src/interfaces/jdbc/postgresql/jdbc1/ResultSet.java.
It works fine (with Daylight saving too).

    434   public Timestamp getTimestamp(int columnIndex) throws SQLException
    435   {
    436     String s = getString(columnIndex);
    437     SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:sszzz");
    438 
    439     if (s != null)
    440       {
    441 //CUT  int TZ = new Float(s.substring(19)).intValue();
    442 //CUT  TZ = TZ * 60 * 60 * 1000;
    443 //CUT  TimeZone zone = TimeZone.getDefault();
    444 //CUT  zone.setRawOffset(TZ);
    445 //CUT  String nm = zone.getID();
    446 //CUT  s = s.substring(0,19) + nm;
    447     try {
    448       java.util.Date d = df.parse(s);
    449       return new Timestamp(d.getTime());
    450     } catch (ParseException e) {
    451       throw new PSQLException("postgresql.res.badtimestamp",new Integer(e.getErrorOffset()),s);
    452     }
    453       }
    454     return null;                // SQL NULL
    455   }
    456 
--------------------- Explanation of the real problem
First problem: SimpleDateFormat was not parsing EST timezone ID if locale(pt_BR) is present.
I thought timezone's ID (EST, PST, etc.) was universal, not depending on locales.

Looking for Blackdown's classes source code (java/text/SimpleDateFormat.java,
java/util/TimeZone.java and java/util/Locale.java), I found that SimpleDateFormat works with
GMT+HH:MM, Locale timezone ID and RFC822 (just offset) and all locale's timezone was in
java/text/resources/DateFormatzoneData_*.java. So if the locale is not in resources (pt_BR, for example),it recognizes just GMT ID. Is it a Blackdown java classes bug ?

Second problem: But why programa aborts ? It has a message for this.
The abortion reason is:

java.lang.IllegalArgumentException: Argument # > Arg length
java.lang.IllegalArgumentException: Argument # > Arg length
        at java.text.MessageFormat.format(MessageFormat.java)
        at java.text.MessageFormat.format(MessageFormat.java)
        at java.text.MessageFormat.format(MessageFormat.java)
        at postgresql.util.PSQLException.translate(PSQLException.java:83)
        at postgresql.util.PSQLException.<init>(PSQLException.java:57)
        at postgresql.jdbc1.ResultSet.getTimestamp(ResultSet.java:451)
        at postgresql.jdbc1.ResultSet.getObject(ResultSet.java:733)
        at example.psql.displayResult(psql.java:122)
        at example.psql.processLine(psql.java:88)
        at example.psql.<init>(psql.java:58)
        at example.psql.main(psql.java:204)

So, I put something like "System.out.println("message="+message+" NArgs="+args.length)" in
tranlate function of src/interfaces/jdbc/postgresql/util/PSQLException.java.

For my surprise, the result was: message=Bad Timestamp Format at {1} in {2} NArgs=2

The message just requires two args. FOR THIS, I HAVE NO SOLUTION.

Best Regards,

Ricardo Coelho.
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