What is Association classes in UML diagrams

In the next video, you will learn about association class.

In the previous video, you learnt about association class, which is used to capture the properties of the relationship between different classes. For example, when an Admin pays an invoice raised by a supplier, a transaction takes place. This transaction will have several properties which can be captured in the class diagram as shown below.

Video Transcript

When there is a relationship between two classes, generally we call it as association. More often the association between two classes are just labeled on top of the line between these two classes.

More often this label is just not enough. It needs lot more information than just a label. So to add more details to just this label, the whole relationship or the association can in itself be represented with a whole different class. For example, there is an admin class and there is an invoice class. An admin views the invoice and decides to pay for the invoice when he pays. Let's say the relationship is called as transacts. The whole transaction could have a bunch of details, the amount to be paid and so on and so forth. So these transaction details can be represented as a whole together separate a class. So association classes are just a few more detailed information in addition to the label. On top of the relationship between these two classes.

Video Recap

• Association is a relationship between two classes that is labeled on top of the line between them.

• However, this label is often not enough and more information is needed to describe the association.

• Association classes represent the whole relationship or association between two classes as a separate class with more detailed information.

• For example, an admin class and an invoice class can have a transact relationship, which can include details such as the amount to be paid.

• Association classes provide additional information beyond just the label on the relationship between two classes.

In the next video, you will learn how to represent an aggregation relationship, a composition relationship, an association class, constraints and notes in draw.io.

In the previous video, you learnt how to create and represent an association class using draw.io.

In this segment, you have been made familiar to the concept of Association classes in Class Diagram.