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Java Extended
course content

Course Content

Java Extended

Java Extended

1. Deep Java Structure
How Does the Compiler Works?Data Transfer in JavaFinal KeywordImporting LibrariesUsing Libraries In Our CodeTernary OperatorEnhanced Switch Statement
2. Methods
What is a Method?Creating Our Own MethodsChallenge: Names Starting with Letter BVoidMethods PracticeMethod Overloading RecursionChallenge: Find Maximum and Minimum in Array
3. String Advanced
Deeper into StringMethod split()Challenge: Uppercase Even WordsindexOf() MethodChallenge: Finding the Longest Wordtrim() MethodChallenge: Email Validation
4. Classes
What is Class?Main Class and MethodAccess ModifiersClass CreationChallenge: Get Information About the ObjectConstructorChallenge: Team ConstructorMethod toString()Challenge: Parrot Information Display
5. Classes Advanced
Complex Classes UsageChallenge: Pet and Owner RelationshipPrivate ModifierChallenge: Animal Information DisplayGetter and SetterChallenge: Updating User InformationSummary

bookClass Creation

Class Syntax

The syntax for creating a class is quite simple. Let's take a look at an example with the class Person:

java

Person

copy

              
123

            
class Person {

}

This is all it takes to create a class. However, it will be useless to us if it's empty. Therefore, we should add fields to it. Let's assume that our person has a name, gender, and age:

java

Person

copy

              
12345

            
class Person {
    String name;
    String gender;
    int age;
}

And now, let's write a method that allows our Person to report their name and age:

java

Person

copy

              
123456789

            
class Person {
    String name;
    String gender;
    int age;
    
    void introduce() {
        System.out.println("Hi, my name is " + name + " and I am " + age + " years old!");
    }
}
Task
test

Swipe to show code editor

Alice wants to find a friend within a specific age range (25 - 30, inclusive). You need to write a program that checks whether Bob meets Alice's criteria. If Bob's age falls within the specified range, the program should return true; otherwise, it should return false.

  1. In the main method, you need to pass the correct object as the first parameter to the findFriend method.
  2. In the findFriend method, compare the age of the passed object with the specified age range (25 - 30).
  3. If the object falls within the age range, return true; otherwise, return false.
  4. To display the result on the screen, use the foundFriend variable, which stores the result of the search.

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Section 4. Chapter 4
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bookClass Creation

Class Syntax

The syntax for creating a class is quite simple. Let's take a look at an example with the class Person:

java

Person

copy

              
123

            
class Person {

}

This is all it takes to create a class. However, it will be useless to us if it's empty. Therefore, we should add fields to it. Let's assume that our person has a name, gender, and age:

java

Person

copy

              
12345

            
class Person {
    String name;
    String gender;
    int age;
}

And now, let's write a method that allows our Person to report their name and age:

java

Person

copy

              
123456789

            
class Person {
    String name;
    String gender;
    int age;
    
    void introduce() {
        System.out.println("Hi, my name is " + name + " and I am " + age + " years old!");
    }
}
Task
test

Swipe to show code editor

Alice wants to find a friend within a specific age range (25 - 30, inclusive). You need to write a program that checks whether Bob meets Alice's criteria. If Bob's age falls within the specified range, the program should return true; otherwise, it should return false.

  1. In the main method, you need to pass the correct object as the first parameter to the findFriend method.
  2. In the findFriend method, compare the age of the passed object with the specified age range (25 - 30).
  3. If the object falls within the age range, return true; otherwise, return false.
  4. To display the result on the screen, use the foundFriend variable, which stores the result of the search.

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Everything was clear?

How can we improve it?

Thanks for your feedback!

Section 4. Chapter 4
toggle bottom row

bookClass Creation

Class Syntax

The syntax for creating a class is quite simple. Let's take a look at an example with the class Person:

java

Person

copy

              
123

            
class Person {

}

This is all it takes to create a class. However, it will be useless to us if it's empty. Therefore, we should add fields to it. Let's assume that our person has a name, gender, and age:

java

Person

copy

              
12345

            
class Person {
    String name;
    String gender;
    int age;
}

And now, let's write a method that allows our Person to report their name and age:

java

Person

copy

              
123456789

            
class Person {
    String name;
    String gender;
    int age;
    
    void introduce() {
        System.out.println("Hi, my name is " + name + " and I am " + age + " years old!");
    }
}
Task
test

Swipe to show code editor

Alice wants to find a friend within a specific age range (25 - 30, inclusive). You need to write a program that checks whether Bob meets Alice's criteria. If Bob's age falls within the specified range, the program should return true; otherwise, it should return false.

  1. In the main method, you need to pass the correct object as the first parameter to the findFriend method.
  2. In the findFriend method, compare the age of the passed object with the specified age range (25 - 30).
  3. If the object falls within the age range, return true; otherwise, return false.
  4. To display the result on the screen, use the foundFriend variable, which stores the result of the search.

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Everything was clear?

How can we improve it?

Thanks for your feedback!

Class Syntax

The syntax for creating a class is quite simple. Let's take a look at an example with the class Person:

java

Person

copy

              
123

            
class Person {

}

This is all it takes to create a class. However, it will be useless to us if it's empty. Therefore, we should add fields to it. Let's assume that our person has a name, gender, and age:

java

Person

copy

              
12345

            
class Person {
    String name;
    String gender;
    int age;
}

And now, let's write a method that allows our Person to report their name and age:

java

Person

copy

              
123456789

            
class Person {
    String name;
    String gender;
    int age;
    
    void introduce() {
        System.out.println("Hi, my name is " + name + " and I am " + age + " years old!");
    }
}
Task
test

Swipe to show code editor

Alice wants to find a friend within a specific age range (25 - 30, inclusive). You need to write a program that checks whether Bob meets Alice's criteria. If Bob's age falls within the specified range, the program should return true; otherwise, it should return false.

  1. In the main method, you need to pass the correct object as the first parameter to the findFriend method.
  2. In the findFriend method, compare the age of the passed object with the specified age range (25 - 30).
  3. If the object falls within the age range, return true; otherwise, return false.
  4. To display the result on the screen, use the foundFriend variable, which stores the result of the search.

Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
Section 4. Chapter 4
Switch to desktopSwitch to desktop for real-world practiceContinue from where you are using one of the options below
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