// Method to open a file for sequential read-only.
private void openFile() {
// Define local primitive(s).
String contents = new String();
// If a file is open, prompt to save the file before dismissing content
// and reference.
if (!file.toString().equals("")) {
// Close the existing file.
closeFile();
} // End of if file not null or not equal to a zero String.
// Open a file.
fileName = FileIO.findFile(this);
// If a file name is returned.
if (fileName != null) {
// Read file.
contents = FileIO.openFile(this, fileName);
// Verify that the JTextAreaPanel is empty.
if (sender.isTextAreaEmpty()) {
// Set JTextAreaPanel.
sender.setText(contents);
} // End of if JTextAreaPanel is empty.
else {
// Reset JTextAreaPanel by replacing the range.
sender.replaceRange(contents, 0, sender.getText().length());
} // End of else JTextAreaPanel is not empty.
// Set file open flag to true.
fileOpen = true;
} // End of if a fileName is selected.
} // End of openFile method.
