Can't get console up and running in eclipse

Question

Hi tried to get the system.console() up with a console object, using code from java tutorial, here: http://java.sun.com/docs/books/tutorial/essential/regex/test_harness.html
But when I try to run the code, the console never pops up and the return is null. I am using eclipse with java 1.6 installed. I have programmed on this with many other classes before and have not had a problem.
I am using the fall 07 version of eclipse on windows vista home premium.
Please advise
Thanks
-Z
Edited by: zhuberg on Aug 16, 2008 9:19 PM
Edited by: zhuberg on Aug 16, 2008 9:22 PM

Answer 1

Hi tried to get the system.console() up with a console object,Do you mean you invoked System.console()? If so, you should take the [API docs|http://java.sun.com/javase/6/docs/api/java/lang/System.html#console()] at face value: "Returns the unique Console object associated with the current Java virtual machine, if any". If any.
If I compile and run the following within Eclipse:
public class ConsoleEg {
    public static void main(String[] args) {
        System.out.println("System.console()=" + System.console());
}then I get the output:
{noformat}
    System.console()=null
{noformat}The [Console documentation|http://java.sun.com/javase/6/docs/api/java/io/Console.html] elaborates: "Whether a virtual machine has a console is dependent upon the underlying platform and also upon the manner in which the virtual machine is invoked. If the virtual machine is started from an interactive command line without redirecting the standard input and output streams then its console will exist and will typically be connected to the keyboard and display from which the virtual machine was launched. If the virtual machine is started automatically, for example by a background job scheduler, then it will typically not have a console.
If this virtual machine has a console then it is represented by a unique instance of this class which can be obtained by invoking the System.console() method. If no console device is available then an invocation of that method will return null."
Perhaps you should use the other methods for I/O: buffered reader and the print stream methods.