oracle.jbo.domain.Number和java.lang.Number的区别

Question

I'm re-learning Java to work on an OAF (Oracle Application Framework) Page and I'm getting an error below due to a line in my code:

Code Line

Number attrValue = (Number)currRow.getAttribute("IctTrxHdrId");

Error Message

oracle.apps.fnd.framework.OAException: java.lang.ClassCastException: oracle.jbo.domain.Number

I was able to resolve this taking the advice from a post in Oracle Forums that i should import oracle.jbo.domain.Number so that attrValue will use the oracle.jbo.domain.Number class instead of java.lang.Number .

Also read from another post on SO that I can use the below syntax to use oracle.jbo.domain.Number :

oracle.jbo.domain.Number attrValue = (oracle.jbo.domain.Number) currRow.getAttribute("IctTrxHdrId");

I'm curious, What's the difference between the two classes?

Answer 1

The class oracle.jbo.domain.Number is a wrapper around the class java.lang.Number .

The goal is to have a domain object in the sense of the Oracle Fusion Middleware .

From the documentation :

The oracle.jbo.domain.* classes, also known as the "JBO Generic Domains", provide lightweight wrappers for the native Java data types, such as java.lang.Number and java.sql.Date. These wrappers allow the native Java datatypes to be represented as domain objects. A domain is a class for scalar data values that can be accessed in a tier-independent manner, and that has no inherent implication on mappability to database columns.