AddressBook Level 3 (AB3) is a desktop app for managing contacts, optimized for use via a Line Interface (CLI) while still having the benefits of a Graphical User Interface (GUI). If you can type fast, AB3 can get your contact management tasks done faster than traditional GUI apps.
Ensure you have Java 17 or above installed in your Computer.
Mac users: Ensure you have the precise JDK version prescribed here.
Download the latest .jar file from here.
Copy the file to the folder you want to use as the home folder for your AddressBook.
Open a command terminal, cd into the folder you put the jar file in, and use the java -jar addressbook.jar command to run the application.
A GUI similar to the below should appear in a few seconds. Note how the app contains some sample data.

Type the command in the command box and press Enter to execute it. e.g. typing help and pressing Enter will open the help window.
Some example commands you can try:
list : Lists all contacts.
add n/John Doe p/98765432 e/johnd@example.com a/John street, block 123, #01-01 : Adds a contact named John Doe to the Address Book.
delete 3 : Deletes the 3rd contact shown in the current list.
clear : Deletes all contacts.
exit : Exits the app.
Refer to the Features below for details of each command.
Notes about the command format:
Words in UPPER_CASE are the parameters to be supplied by the user.
e.g. in add n/NAME, NAME is a parameter which can be used as add n/John Doe.
Items in square brackets are optional.
e.g n/NAME [t/TAG] can be used as n/John Doe t/friend or as n/John Doe.
Items with … after them can be used multiple times including zero times.
e.g. [t/TAG]… can be used as (i.e. 0 times), t/friend, t/friend t/family etc.
Parameters can be in any order.
e.g. if the command specifies n/NAME p/PHONE_NUMBER, p/PHONE_NUMBER n/NAME is also acceptable.
Extraneous parameters for commands that do not take in parameters (such as help, list, exit and clear) will be ignored.
e.g. if the command specifies help 123, it will be interpreted as help.
If you are using a PDF version of this document, be careful when copying and pasting commands that span multiple lines as space characters surrounding line-breaks may be omitted when copied over to the application.
helpShows a message explaining how to access the help page.
Format: help
addAdds a person to the address book.
Format: add n/NAME p/PHONE_NUMBER e/EMAIL a/ADDRESS [t/TAG]…
Tip: A person can have any number of tags (including 0)
Examples:
add n/John Doe p/98765432 e/johnd@example.com a/John street, block 123, #01-01add n/Betsy Crowe t/friend e/betsycrowe@example.com a/Newgate Prison p/1234567 t/criminallistShows a list of all persons in the address book.
Format: list
editEdits an existing person in the address book.
Format: edit INDEX [n/NAME] [p/PHONE] [e/EMAIL] [a/ADDRESS] [t/TAG]…
INDEX. The index refers to the index number shown in the displayed person list. The index must be a positive integer 1, 2, 3, …t/ without
specifying any tags after it.Examples:
edit 1 p/91234567 e/johndoe@example.com Edits the phone number and email address of the 1st person to be 91234567 and johndoe@example.com respectively.edit 2 n/Betsy Crower t/ Edits the name of the 2nd person to be Betsy Crower and clears all existing tags.findFinds persons whose names contain any of the given keywords.
Format: find KEYWORD [MORE_KEYWORDS]
hans will match HansHans Bo will match Bo HansHan will not match HansOR search).
e.g. Hans Bo will return Hans Gruber, Bo YangExamples:
deleteDeletes the specified person from the address book.
Format: delete INDEX
INDEX.Examples:
list followed by delete 2 deletes the 2nd person in the address book.find Betsy followed by delete 1 deletes the 1st person in the results of the find command.clearClears all entries from the address book.
Format: clear
exitExits the program.
Format: exit
AddressBook data are saved in the hard disk automatically after any command that changes the data. There is no need to save manually.
AddressBook data are saved automatically as a JSON file [JAR file location]/data/addressbook.json. Advanced users are welcome to update data directly by editing that data file.
Caution:
If your changes to the data file makes its format invalid, AddressBook will discard all data and start with an empty data file at the next run. Hence, it is recommended to take a backup of the file before editing it.
Furthermore, certain edits can cause the AddressBook to behave in unexpected ways (e.g., if a value entered is outside the acceptable range). Therefore, edit the data file only if you are confident that you can update it correctly.
[coming in v2.0]Details coming soon ...
Q: How do I transfer my data to another Computer?
A: Install the app in the other computer and overwrite the empty data file it creates with the file that contains the data of your previous AddressBook home folder.
preferences.json file created by the application before running the application again.help command (or use the Help menu, or the keyboard shortcut F1) again, the original Help Window will remain minimized, and no new Help Window will appear. The remedy is to manually restore the minimized Help Window.| Action | Format, Examples |
|---|---|
| Add | add n/NAME p/PHONE_NUMBER e/EMAIL a/ADDRESS [t/TAG]… e.g., add n/James Ho p/22224444 e/jamesho@example.com a/123, Clementi Rd, 1234665 t/friend t/colleague |
| Clear | clear |
| Delete | delete INDEXe.g., delete 3 |
| Edit | edit INDEX [n/NAME] [p/PHONE_NUMBER] [e/EMAIL] [a/ADDRESS] [t/TAG]…e.g., edit 2 n/James Lee e/jameslee@example.com |
| Find | find KEYWORD [MORE_KEYWORDS]e.g., find James Jake |
| List | list |
| Help | help |