Java Class Attributes Flashcards

Study Notes

Java Class Attributes

Class attributes, also known as fields, are variables defined within a class.

Example class "MyClass" with attributes x and y:

public class MyClass {
    int x = 5;
    int y = 3;
}

Accessing Attributes

Attributes can be accessed using an object of the class and the dot syntax.
Example of creating an object "myObj" to print the value of x:
```
MyClass myObj = new MyClass();
System.out.println(myObj.x);
```

Class Attribute Format

General format for declaring class attributes:

public class ClassName {
    type variableName = value;
}

Modifying Attributes

Attribute values can be modified after object creation.

Example of setting x to 40:

myObj.x = 40;
System.out.println(myObj.x); // Outputs: 40

Overriding Attribute Values

Attribute values can be overridden, changing their current value.
Example of changing x to 25 from an initial value of 10:
```
myObj.x = 25; // x is now 25
```

Final Keyword for Attributes

Declaring an attribute as final prevents its value from being changed.

Example using final:

final int x = 10; // Cannot assign a new value

Effect of Multiple Objects

Each instance of a class can have distinct attribute values.
Changing an attribute in one object does not affect another:
- Example where myObj1.x remains unchanged while myObj2.x is set to 25.

Multiple Attributes

A class can have multiple attributes defined.

Example of a "Person" class with attributes fname, lname, and age:

public class Person {
    String fname = "John";
    String lname = "Doe";
    int age = 24;
}

Accessing these attributes can yield formatted output of an individual's details:
- Output: "Name: John Doe" & "Age: 24"

Description

Test your knowledge of Java class attributes with these flashcards. Each card will help you understand terms like 'variables' and 'fields' within the context of a Java class. Enhance your Java programming skills with focused practice.