From the course: Advanced Java Programming
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The substitution principle in Java - Java Tutorial
From the course: Advanced Java Programming
The substitution principle in Java
- [Instructor] The substitution principle, which is also known as the Liskov Substitution Principle is an important concept in object-oriented programming because it allows you to write maintainable and reusable code. The name makes it sound like it's going to be a complicated concept, but it is actually very simple. It just means that if you have a variable of a given type you can assign it to a value that is a subtype of that type. In this example I have a simple class called Building which simply overwrites the toString method to print out that it is a Building. I then have another simple class called Office which extends the Building class and overrides the toString method again to print out that this is an office. I then have a Main class. In the main method I have created a building variable and assigned it to a new Building object. I have then created a second building object. But instead of assigning it to a building, I have assigned it to a new Office object. In this class I…
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