Archive for the 'Errors' Category

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

kuttikaranam

Today I had a new install of Mandriva 2008 linux. I wrote a java code to test the mysql connectivity. It ended with the following exception.

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
Last packet sent to the server was 0 ms ago.

Alas, deeper google search gives me a solution that told about the mysql connectivity parameter in /etc/my.cnf

skip-networking

This parameter has been added for some security related reasons. Really I dont know what it is. I just removed that line, which solved this issue.

java.util.zip.ZipException: invalid CEN header (encrypted entry)

friends,This week started with some more problems :). Nothing to worry, problems only feed us! Otherwise, who will give us job!!! Today I was trying to unzip a zip file and read the contents inside the file, using java.util.zip.ZipFile. It was working fine till I increased the file size. The zip file is around 160MB, and the single file inside that zip file is 4.5GB contains raw text. I hit with the exception

java.util.zip.ZipException: invalid CEN header (encrypted entry)

Pathetic, I was totally helpless! Later I came to know that It is a open bug in java, which will not support above 3.2G!  I am in darkness. Latermy lead had pointed out that is due to java’s non-compliance to zip64, which is fixed in jdk1.6, 24th build. I need to get it installed and get rid of this issue!

java.sql.SQLException: ORA-01000: maximum open cursors exceeded

As I have told you in my previous post, I was trying to read from a table within a loop. I am opening a new connection, new statement and firing the query to get the resultset. It was working fine for a few records, finally it dies with this exception

java.sql.SQLException: ORA-01000: maximum open cursors exceeded

Alas, I forgot to close the resultset!!

Next Page »