This lesson uses a simple application that we provide to you.
- Create a file named
Count.javaon your local computer by either copying or downloading theCount.javasource code. The examples in this lesson assume that you placecountin theC:\Testdirectory.
- The
countapplication needs to access a text file containing the data it will process. Download a sample data file here, or use any other convenient text file as data.
Important: Put your data file into a directory other than the directory containing your downloadedcountclass file. We suggestC:\TestData\data.
Later in this lesson you will see how an application running under a security manager cannot read a file unless it has explicit permission to do so. However, an application can always read a file from the same directory (or a subdirectory). It does not need explicit permission.
- Compile and then run the
Countapplication to see what it does.
When you run thecountapplication, you need to specify (as an argument) the path name of a file to be read.
java Count C:\TestData\data
Here is a sample run:
C:\Test>java Count C:\TestData\data Counted 65 chars.