Best Practice??

Hi All,
I'm realtively new to linux and postgresql. My application gets the
following error when it tries to store a record:
java.lang.NullPointerException
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:243)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:190)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at
org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at
org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2347)
at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at
org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:170)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:170)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:468)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at
org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at
org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:1027)
at
org.apache.catalina.connector.http.HttpProcessor.run(HttpProcessor.java:1125)
at java.lang.Thread.run(Thread.java:566)
at null.null(Unknown Source)
at null.null(Unknown Source)
at null.null(Unknown Source)
at null.null(Unknown Source)
at null.null(Unknown Source)
at java.lang.Thread.run(Thread.java:566)

********************************
When I execute the same instruction at the command line it stores it
successfully. I'm not sure its related but I wonder if there is
something I am doing wrong with setting file permissions.
1. Any idea what's causing this error?
2. What is the Best Practice for setting file ownership and log on for
development?
I have been doing most of my work logging on as root but I know that is
not best. When I changed to another user name I'm afraid it has caused
the application to not see the database files or other developed files.

Your thoughts would be appreciated,
Phil Campaigne