Part 3: Java Fundamentals for Test Automation

Since Appium tests are often written in Java, it’s important to understand some basic Java concepts. Don’t worry—we’ll cover only the essentials so you can start automating quickly

Variables & Data Types
Summary
Hands-on Practice with Eclipse
What You Just Practiced

1. Variables & Data Types

Variables store data like numbers or text.
Common data types:
- int — stores whole numbers (e.g., 10)
- double — stores decimal numbers (e.g., 5.5)
- boolean — true or false
- String — stores text (e.g., “Hello”)

Example:

				
					int age = 25;
double price = 19.99;
boolean isEnabled = true;
String name = "Appium";

2. Methods and Functions

A method is a block of code that performs a task.
You can call methods to reuse code.

Example:

				
					public void printName() {
    System.out.println("Appium Tutorial");
}

To call it: printName();

3. Classes & Objects

A class is like a blueprint for creating objects.
An object is an instance of a class.Example:

Example:

				
					public class Car {
    String color;

    public void drive() {
        System.out.println("Car is driving");
    }
}

// Creating an object
Car myCar = new Car();
myCar.color = "Red";
myCar.drive();

4. Conditionals (if/else)

Used to make decisions in code.

Example:

				
					int score = 80;

if(score > 70) {
    System.out.println("Test Passed");
} else {
    System.out.println("Test Failed");
}

5. Loops (for, while)

Run the same block of code multiple times.

For loop example:

				
					
for(int i = 0; i < 5; i++) {
    System.out.println("Iteration: " + i);
}

While loop example:

				
					int i = 0;
while(i < 5) {
    System.out.println("Iteration: " + i);
    i++;
}

6. Arrays & Lists

Store multiple values in one variable.

Array example:

				
					int[] numbers = {1, 2, 3, 4};

List example:

				
					import java.util.ArrayList;
ArrayList<String> names = new ArrayList<String>();
names.add("Appium");
names.add("Selenium");

7. Exception Handling (try-catch)

Handle errors

Example:

				
					try {
    int result = 10 / 0;
} catch(ArithmeticException e) {
    System.out.println("Cannot divide by zero");
}

8. Inheritance and OOP Basics

Inheritance lets a class reuse code from another class.

Example:

				
					class Animal {
    void eat() {
        System.out.println("Eating...");
    }
}

class Dog extends Animal {
    void bark() {
        System.out.println("Barking...");
    }
}

Dog d = new Dog();
d.eat();  // Inherited method
d.bark();

9. Packages and File Organization

Packages group related classes together.
Keep your project organized by separating different parts into packages.

Example:

				
					package com.appium.tests;

public class SampleTest {
    // test code here
}

Summary:

Concept

Why it matters for Appium tests

Variables

Store data like element IDs, text, etc.

Methods

Organize reusable code blocks

Classes & Objects

Structure your tests and page objects

Conditionals

Handle test verification logic

Loops

Run repetitive actions, like clicking multiple buttons

Arrays & Lists

Manage groups of test data

Exception Handling

Handle errors without crashing tests

Inheritance

Reuse and extend test functionalities

Packages

Keep test code clean and maintainable

Hands-on Practice with Eclipse

Let’s get our hands dirty by writing and running basic Java code using Eclipse IDE, which will be your main tool while building your Appium automation framework.

Step 1: Install Eclipse (If You Haven’t Yet)

Go to https://www.eclipse.org/downloads/
Download Eclipse IDE for Java Developers
Install and launch Eclipse
Select a workspace folder (your working directory)

Step 2: Create a New Java Project

Open Eclipse
Go to File → New → Java Project
Give your project a name (e.g., JavaBasicsAppium)
Click Finish

Step 3: Create a Java Class

Right-click on the src folder inside your new project
Click New → Class
Give the class a name (e.g., PracticeBasics)
Check the box for public static void main(String[] args)
Click Finish

Step 4: Write Some Simple Java Code

Paste this code inside the class:

				
					public class PracticeBasics {
    public static void main(String[] args) {
        System.out.println("Hello, Appium World!");
        
        int a = 10;
        int b = 20;
        int sum = a + b;
        
        System.out.println("The sum is: " + sum);
    }
}

Step 5: Run the Program

Right-click on the file → Run As → Java Application
You should see the output in the Console tab at the bottom:

				
					Hello, Appium World!
The sum is: 30

Our Resources

Part 3: Java Fundamentals for Test Automation

Table of Contents

1. Variables & Data Types

2. Methods and Functions

3. Classes & Objects

4. Conditionals (if/else)

5. Loops (for, while)

6. Arrays & Lists

7. Exception Handling (try-catch)

8. Inheritance and OOP Basics

9. Packages and File Organization

Summary:

Concept

Why it matters for Appium tests

Hands-on Practice with Eclipse

Step 1: Install Eclipse (If You Haven’t Yet)

Step 2: Create a New Java Project

Step 3: Create a Java Class

Step 4: Write Some Simple Java Code

Step 5: Run the Program

What You Just Practiced:

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