External Interfaces |
Example - Creating and Using a Phone Book
The example's main function, phonebook
, can be called either with no arguments, or with one argument, which is the key of an entry that exists in the phone book. The function first determines the directory to use for the phone book file.
If no phone book file exists, it creates one by constructing a java.io.FileOutputStream
object, and then closing the output stream. Next, it creates a data dictionary by constructing an object of the Java API class, java.util.Properties
, which is a
subclass of java.util.Hashtable
for storing key/value pairs in a hash table. For the phonebook
program, the key is a name, and the value is one or more telephone numbers.
The phonebook
function creates and opens an input stream for reading by constructing a java.io.FileInputStream
object. It calls load on that object to load the hash table contents, if it exists. If the user passed the key to an entry to look up, it looks up the entry by calling pb_lookup
, which finds and displays it. Then, the phonebook
function returns.
If phonebook
was called without the name argument, it then displays a textual menu of the available phone book actions:
The menu also has a selection to exit the program. The function uses MATLAB functions to display the menu and to input the user selection.
The phonebook
function iterates accepting user selections and performing the requested phone book action until the user selects the menu entry to exit. The phonebook
function then opens an output stream for the file by constructing a java.io.FileOutputStream
object. It calls save
on the object to write the current data dictionary to the phone book file. It finally closes the output stream and returns.
Running the serialexample Program | Description of Function phonebook |
© 1994-2005 The MathWorks, Inc.