When running Java standalone class in Websphere, there's a Common tab in the launch configuration.
This is what websphere help says:
When a launch configuration is executed, the standard output and standard input might display output data and read input data, respectively. By default, the Console view is used for both the standard output and standard input. The standard input may be disabled and the standard output may be changed to write or append to a local file in the Standard Input and Output pane of the Common tab. To disable the standard input, clear the Allocate Console check box; Allocate Console is necessary for input.
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