Use Globally Defined Constants
Java: How To
Via a class
This technique is useful for constants defined on a corporate level. They are very generic by nature. The CONSTANT class is included in the classpath.
public class CONSTANT
{
public static final integer SUCCESS = 1;
public static final integer FAILURE = -1;
public static final integer NOTFOUND = 0;
}
|
Since the members of the class are defined as "static", there is no need to instantiate the class. To use a constant, simply use CONSTANT.[constant name]
if (myMethod()==CONSTANT.SUCCESS)
{
...;
}
else
{
...;
}
|
Via an interface
This technique can be used if the constants are not really global but especially designed to be used in a specific application for example. An application-level class needs to implement the interface to be able to see the constant definitions.
public interface APPCONSTANT
{
public static final String APPNAME = "The Super APP";
public static final String APPVERSION = "version 1.0";
public static final String DBDRIVER = "oracle.jdbc.driver.OracleDriver";
}
|
To use a constant, simply implement the interface
public class TheAppFrame extends Frame implements APPCONSTANT
{
TheAppFrame
{
...
setTitle(APPNAME);
...
}
...
}
|
| 
