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44 lines
1.3 KiB
44 lines
1.3 KiB
2 years ago
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# University
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### Instructions
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Create a class named `University`.
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Its attributes:
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- name - `private string`
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- city - `private string`
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- ranking - `private int?`
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- getters:
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- name
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- city
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- ranking
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- Constructor:
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- name - `required`
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- city - `required`
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- ranking - `optional`
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### Encapsulation
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Sometimes we need to limit access to class attributes so that it can be accessed only from the class itself. This concept is called **Encapsulation.**
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In Dart we can make attributes **private** (meaning that they can be changed or used only in the instances of this class) by putting underscore (\_) in the beginning of fields' or methods' name.
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Bear in mind that in Dart there is no Encapsulation on a class level. According to Dart's documentation:
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- Importing libraries can help you create a modular and shareable code base. Libraries not only provide APIs, but are unit of privacy: private variables, i.e. starting with an underscore (\_) are visible only inside the library. Every Dart app is a library, even if it doesn’t use a library directive.
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Still, even on a class level it is a good practice to declare private values and not to use values that are intended to be private.
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```dart
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class Person {
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bool _hunger = true;
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void feed() {
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this._hunger = false;
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}
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}
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```
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