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SavaJe OS 1.1.0

app_env(doc)

The SavaJe OS application environment

Java applications running under SavaJe OS execute in a single Java virtual machine (JVM). When an application is launched, whether from the command line or from a GUI shell, a new Java process (JProc ) is created.

Each JProc receives its own storage block for the values of statics. From the application programmer's point of view, creating a new JProc is just like starting up a new JVM. Static method calls and static fields refer only to the current JProc : there is no interference with other calls or fields in different JProc s. At the same time, running multiple JProc s in a single JVM saves SavaJe OS the overhead of creating multiple JVMs and multiple copies of common classes.

Each JProc also inherits a copy of the current system properties, which becomes its local environment, to use and to modify during its operation.

For example, the following program prints out the value of the system property user.name :

public class getProp {
    public static void main (String[] args) {
        System.out.println("user.name: " + System.getProperty("user.name"));
    }
}

In this example, the application uses the system properties to find out the current value of user.name .

Once an application has a copy of the system properties, it can be manipulated like any java.util.Properties object.

SEE ALSO

policy(shell)
prop(shell)
run(shell)
run_java(doc)