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Answer:

Yes. In fact, this is what is done with input redirection.


Input Stream from a File

scanner reading integers

With file input redirection, a disk file is connected to the standard input stream used by a Scanner object. You can also construct a scanner object that connects to a disk file:

// create a File object
File file = new File("myData.txt");

// connect a Scanner to the file
Scanner scan = new Scanner( file );      

These statements first create a File object. This is a software object that represents a file name. Creating a File object does not create a disk file. Next a Scanner object is constructed and connected to the actual file.

The same methods can be used with this Scanner object as with standard input. Characters than can be converted into an int can be scanned in using nextInt() as with the standard input stream.

Bug Alert! The following will not work:

Scanner scan = new Scanner( "myData.txt" );      

This creates a Scanner that scans through the String given as its argument.


QUESTION 3:

Must the disk file used with Scanner be a text file?