What is IOU?

A free desktop application that helps two people keep track of money owed by one to the other. It would typically be useful to a couple, roommates, or any two people that incur shared expenses and/or lend money to each other. IOU keeps a record of all transactions and calculates the current balance (shown in red below).

How does it work?

IOU supports two types of transactions: payments and expenses.

Expenses

Shared expenses are recorded in the right-hand table. It is assumed that all shared expenses should be split 50/50. For example, if Ann and Bob have a current balance of $0 (neither owes the other anything), then they receive a gas bill for $100 of which Ann pays $20 and Bob pays $80. This expense should be entered like so:

After this expense is saved, the current balance will indicate that Ann owes Bob $30.

Payments

A payment occurs when one party gives money directly to the other. Typically, a payment will either be a loan or repayment of an outstanding debt. For example, following payment of the gas bill mentioned above, Ann owes Bob $30. Ann repays this debt by transferring $30 to his bank account. This should be entered as a payment like so:

After this payment is saved, the current balance will indicate that neither Ann nor Bob owes the other anything.

Archive

By default all payments and expenses entered since the beginning of time are displayed by IOU. When an archive is performed all payments and expenses that were entered prior to the archive are permanently hidden, but the current balance is carried forward. In other words, an archive clears the list of payments and expenses shown in IOU without affecting the current balance.

Installation

Prerequisites

• Java, version 5 or later
• MySQL, tested with version 5.5 but any modern version should work
• Maven, tested with version 3.0.3, but any 2.X or 3.X version should work

Configuration

The steps below only need to be performed once, before you run the application for the first time:

• Create a schema in MySQL named iou. If the MySQL server is not running on the default port (3306) on localhost (or you didn't name the schema iou), make the appropriate changes to the jdbc.url config parameter in resources/config.properties
• Create two MySQL users that have read-write access to the iou schema
• In config.properties set ann.username to the MySQL login of one of the users and set bob.username to the MySQL login of the other user
• In the same file, set ann.name and bob.name to the names that IOU will display for each of these users
• If $ is not used as the currency symbol in your locale, also set currency.symbol to whatever you wish to use instead

Run IOU

With Maven

To build and run the application with Maven, execute the command below from the project's root directory:

mvn compile exec:java -Dexec.mainClass=iou.gui.AppLauncher

When the application starts, the selected user should use their MySQL password to login.

Without Maven

If you wish to run the application on a machine that doesn't have Maven installed, you can build a self-contained JAR file by executing the following Maven command from the project's root directory:

mvn assembly:assembly

This will create a jar file in the target directory named iou.jar. This file can be run on any machine that has Java installed via the command java -jar iou.jar.