Java sticky instances of class com.mysql.jdbc.Field aggregating -


i noticed (via jmap+jhat) app leaking storing many instances com.mysql.jdbc.field class
- double checked code make sure closing preparedstatements, find few missing didn't change outcome.
- preparedstatement created , closed right away
- several others created @ start , reused many times
- using org.apache.tomcat.jdbc.pool.datasource connection pool

what can cause type of behavior?

are closing of preparedstatements / result sets using:

preparedstatement stmt (possible assignment here); try {  // work prepared statement  resultset rs;  try  {    while (rs.next()) ...    // process results  }   {    rs.close();  } } {   stmt.close(); }

so guarantee result sets closed when finished (regardless of exceptions) , statements closed (regardless of exceptions)? there other ways write that, idea same.

if you're doing of properly, unless have many references it's taking inordinate amount of memory, it's ok , nothing needs done it.


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