JSON test data in Selenium Java - Test Execution Trace

Test Overview

This test reads user login data from a JSON file and verifies the login functionality on a web page using Selenium in Java.

Test Code - TestNG with Selenium WebDriver

Selenium Java

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.testng.Assert;
import org.testng.annotations.AfterClass;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Test;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.io.File;

public class LoginTestWithJson {
    WebDriver driver;
    JsonNode testData;

    @BeforeClass
    public void setUp() throws Exception {
        System.setProperty("webdriver.chrome.driver", "path/to/chromedriver");
        driver = new ChromeDriver();
        driver.manage().window().maximize();

        ObjectMapper mapper = new ObjectMapper();
        testData = mapper.readTree(new File("src/test/resources/loginData.json"));
    }

    @Test
    public void testLogin() {
        String url = testData.get("url").asText();
        String username = testData.get("credentials").get("username").asText();
        String password = testData.get("credentials").get("password").asText();

        driver.get(url);

        WebElement usernameField = driver.findElement(By.id("username"));
        WebElement passwordField = driver.findElement(By.id("password"));
        WebElement loginButton = driver.findElement(By.id("loginBtn"));

        usernameField.sendKeys(username);
        passwordField.sendKeys(password);
        loginButton.click();

        WebElement welcomeMessage = driver.findElement(By.id("welcomeMsg"));
        Assert.assertTrue(welcomeMessage.isDisplayed(), "Welcome message should be visible after login");
        Assert.assertEquals(welcomeMessage.getText(), "Welcome, " + username + "!");
    }

    @AfterClass
    public void tearDown() {
        if (driver != null) {
            driver.quit();
        }
    }
}

Execution Trace - 8 Steps

Step	Action	System State	Assertion	Result
1	Test setup: ChromeDriver initialized and JSON test data loaded from file	Browser window opened and maximized; JSON data with URL and credentials loaded	—	PASS
2	Browser navigates to URL from JSON data	Browser displays login page at specified URL	—	PASS
3	Find username, password fields and login button by their IDs	All elements located successfully on the login page	—	PASS
4	Enter username and password from JSON data into input fields	Username and password fields filled with test data	—	PASS
5	Click login button	Login form submitted; page transitions to user dashboard	—	PASS
6	Find welcome message element by ID	Welcome message element present on dashboard page	—	PASS
7	Assert welcome message is displayed and text matches expected username	Welcome message visible with text 'Welcome, testuser!'	Assert.assertTrue(welcomeMessage.isDisplayed()) and Assert.assertEquals(welcomeMessage.getText(), 'Welcome, testuser!')	PASS
8	Test teardown: Browser closed	Browser window closed, WebDriver quit	—	PASS

Failure Scenario

Failing Condition: If the JSON file path is incorrect or JSON structure is invalid, or if elements are not found on the page

Execution Trace Quiz - 3 Questions

What is the source of the username and password used in the test?

A They are entered manually during test execution

B They are read from a JSON file before the test runs

C They are hardcoded in the test code

D They are fetched from a database during the test

Key Result

Using JSON test data separates test logic from test data, making tests easier to maintain and reuse with different inputs.

Practice

1. What is the main advantage of using JSON test data in Selenium Java tests?

easy

A. It separates test data from test code for easier maintenance.

B. It makes the test run faster by compiling JSON.

C. It automatically fixes bugs in the test code.

D. It converts Java code into JSON format.

Solution

1. Step 1: Understand JSON role in testing

   JSON stores test data separately from the test code, so data changes don't require code changes.

2. Step 2: Identify benefits of separation

   This separation makes tests easier to maintain and reuse with different data sets.

3. Final Answer:

   It separates test data from test code for easier maintenance. -> Option A

4. Quick Check:

   JSON separates data and code = B [OK]

Hint: Remember: JSON holds data, not code [OK]

Common Mistakes:

• Thinking JSON speeds up test execution
• Believing JSON fixes code bugs automatically
• Confusing JSON with code format

2. Which of the following is the correct way to read a JSON file in Selenium Java using the org.json library?

easy

A. JSONObject obj = new JSONObject(new FileReader("data.json"));

B. JSONObject obj = new JSONObject("data.json");

C. JSONObject obj = new JSONObject(new FileInputStream("data.json"));

D. JSONObject obj = new JSONObject(new BufferedReader("data.json"));

Solution

1. Step 1: Check correct constructor usage

   The org.json library's JSONObject constructor accepts a Reader object to parse JSON text.

2. Step 2: Match with options

   JSONObject obj = new JSONObject(new FileReader("data.json")); uses new FileReader("data.json") which is a Reader, so it is correct.

3. Final Answer:

   JSONObject obj = new JSONObject(new FileReader("data.json")); -> Option A

4. Quick Check:

   JSONObject needs Reader input = A [OK]

Hint: Use FileReader with JSONObject constructor [OK]

Common Mistakes:

• Passing filename string directly to JSONObject
• Using InputStream instead of Reader
• Passing filename string to BufferedReader constructor

3. Given the JSON file data.json with content:

{"username": "user1", "password": "pass123"}

What will the following Java code print?

JSONObject obj = new JSONObject(new FileReader("data.json"));
System.out.println(obj.getString("username"));

medium

A. null

B. pass123

C. user1

D. Throws JSONException

Solution

1. Step 1: Parse JSON content

   The JSON has key "username" with value "user1".

2. Step 2: Call getString("username")

   This returns the string value for key "username", which is "user1".

3. Final Answer:

   user1 -> Option C

4. Quick Check:

   obj.getString("username") = "user1" [OK]

Hint: Match key names exactly to get values [OK]

Common Mistakes:

• Confusing username and password keys
• Expecting null if key exists
• Not handling JSONException properly

4. What is wrong with this Selenium Java code snippet that reads JSON test data?

JSONObject obj = new JSONObject(new FileReader("testdata.json"));
String email = obj.getString("email");
System.out.println(email);

Assuming the JSON file testdata.json does NOT contain the key email.

medium

A. It compiles but does not run.

B. It prints an empty string.

C. It returns null without error.

D. It throws a JSONException at runtime.

Solution

1. Step 1: Understand getString behavior

   Calling getString on a missing key throws JSONException in org.json library.

2. Step 2: Check code effect

   Since "email" key is missing, the code throws JSONException at runtime.

3. Final Answer:

   It throws a JSONException at runtime. -> Option D

4. Quick Check:

   Missing key getString throws exception = D [OK]

Hint: Missing JSON keys cause exceptions, not null [OK]

Common Mistakes:

• Expecting null or empty string instead of exception
• Ignoring exception handling
• Assuming code won't compile

5. You want to run a Selenium test multiple times with different user credentials stored in a JSON array like:

{"users": [{"username": "user1", "password": "pass1"}, {"username": "user2", "password": "pass2"}]}

Which approach correctly reads and uses this JSON data in Java to loop through each user?

hard

A. JSONObject users = obj.getJSONObject("users");
for (int i = 0; i < users.length(); i++) {
String username = users.getString("username");
String password = users.getString("password");
}

B. JSONArray users = obj.getJSONArray("users");
for (int i = 0; i < users.length(); i++) {
JSONObject user = users.getJSONObject(i);
String username = user.getString("username");
String password = user.getString("password");
// use username and password
}

C. String users = obj.getString("users");
for (String user : users) {
// use user
}

D. JSONArray users = obj.getJSONArray("users");
for (int i = 0; i <= users.length(); i++) {
JSONObject user = users.getJSONObject(i);
// use user
}

Solution

1. Step 1: Identify JSON array access

   The key "users" holds a JSON array, so getJSONArray("users") is correct.

2. Step 2: Loop correctly over array

   Loop from 0 to users.length() - 1, get each JSONObject, then extract username and password.

3. Step 3: Check options

   JSONArray users = obj.getJSONArray("users"); for (int i = 0; i < users.length(); i++) { JSONObject user = users.getJSONObject(i); String username = user.getString("username"); String password = user.getString("password"); // use username and password } correctly uses JSONArray, loops with i < length, and extracts data properly.

4. Final Answer:

   JSONArray users = obj.getJSONArray("users"); for (int i = 0; i < users.length(); i++) { JSONObject user = users.getJSONObject(i); String username = user.getString("username"); String password = user.getString("password"); // use username and password } -> Option B

5. Quick Check:

   JSONArray + for loop with i < length = A [OK]

Hint: Use JSONArray and loop i < length, not <= [OK]

Common Mistakes:

• Using getJSONObject instead of getJSONArray for array
• Looping with i <= length causing IndexOutOfBounds
• Treating JSON array as string