From oracle 10gR2 onwards the db parameter 'FAILED_LOGIN_ATTEMPTS' value has been changed from 'unlimited' to 10. This is unnecessary for a development DB, because it may cause the user account to be locked frequently upon invalid credential input.
To get rid of this we can specify the FAILED_LOGIN_ATTEMPTS to be 'unlimited'.
Login as a system user...
Assuming username is "DEV_USER", we must first find the db profile of it...
SQL>select profile from dba_users where username = 'DEV_USER';
Assuming the returned value is 'DEFAULT', we can change the limit of 'FAILED_LOGIN_ATTEMPTS' for the profile DEFAULT as below...
by default SimpleDateFormat parses strings in a lenient way. However, this may result in unexpected output. And, in occasions where parsing is used as a mechanism of enforcing date format validation, lenient parsing may parse a date which is in an invalid format.
To avoid this, lenient parsing should be switched off as follows:
DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd"); dateFormat.setLenient(false);
String is immutable. Thus, manipulating plain Strings creates lots of garbage objects. But, StringBuffer and StringBuilder are mutable.
StringBuffer and StringBuilder are essentially same except StringBuffer's methods are synchronized.
So, in a code segment which is accessed by multiple threads, StringBuffer should be used, and in all other situations StringBuilder is the most suitable. String can be used if it is guaranteed that its objects won't be manipulated later. e.g. converting to uppercase.