ericb wrote:I wanted to pass along that we've experienced several problems in MLS using the latest JRE - Java 6 update 12. When attempting to generate custom reports nothing would happen, or when selecting to print rolls a generic error message would appear with a frowning face
.
I looked in the MLS log and noticed several Null Pointer Exceptions related to Swing, which is the Java UI toolkit implemented by MLS. Prior to this latest release we had Java 6 update 1 in place, so I went to the Java site where they have archived releases (
http://java.sun.com/products/archive/) and downloaded & installed that version. I then removed Java 6 update 12 since MLS continued to use that version, and I coudn't find a way in the Java Control Panel to disable it. Once we were back to the previous version things started working correctly again.
Java can have multiple runtime environments installed on a single system. There is the system wide version that is registered in the registry for use by web browsers and other programs such as OpenOffice. It is the registered version that has a control applet available through the Windows control panel. This control panel applet only interfaces with the registered JRE.
MLS 2.9.3 is deployed using Java(TM) Platform, Standard Edition Runtime Environment Version 6, Update 11. This Java SE Runtime Environment is installed at a separate location from any existing JRE installations to include the registered JRE just discussed. The MLS JRE install location is C:\Program Files\jre6\bin. The registered JRE is installed, by default, at C:\Program Files\Java\jre6\bin.
The MLS JRE does not interface with the Java control panel applet found in the Windows control panel. The MLS JRE has no user interface for control or information. The MLS JRE is copied to a location separate from all other JREs to ensure non-interference with other installations. MLS is currently developed to use only the JRE it has installed and not the registered JRE.
If the registered JRE is installed at the MLS install location then there can be conflicts. I suspect that during the install of the registered JRE the default location was changed from the default to the MLS location.
To ensure separation of the registered JRE and the MLS JRE I would uninstall all versions of Java found in the Windows control panel Add or Remove Programs applet. Then I would reinstall MLS 2.9.3 to ensure the correct JRE for MLS is installed. The last step would be to install the latest JRE, version 12, in another location. This can be ensured by carefully looking for the install location prompt during the install of Java version 12 and making sure it does not select the MLS JRE install location.
In following these procedures only two JRE versions should exist on an Church administrative (clerk) computer, update 11 for MLS and update 12 for the registered version.
Edit: I forgot to add that there can be more than one registered JRE version installed for the system. When there is more than one version installed and registered you can use the Windows Java control panel applet to select which registered versions you would like enabled. Since the MLS JRE is not registered it is not available to be enabled or disabled. However, you can can register the MLS JRE to be available to other programs. This is done through the Windows Java control panel applet. But I do not recommend this for Church administrative computers.