JSON test data in Selenium Java - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is JSON test data used for in Selenium Java testing?

JSON test data is used to store input values and expected results in a structured format, making tests easier to maintain and data-driven.

intermediate

How do you read JSON test data in Selenium Java?

You can read JSON test data using libraries like Jackson or Gson to parse the JSON file into Java objects for use in tests.

beginner

Why is using JSON test data better than hardcoding values in Selenium tests?

JSON test data separates test logic from data, allowing easy updates to test inputs without changing code, improving test flexibility and readability.

beginner

Show a simple JSON structure for login test data.

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

intermediate

What is a common mistake when using JSON test data in Selenium Java?

A common mistake is not validating JSON structure or handling exceptions when reading the file, which can cause test failures.

What format is JSON test data stored in?

A Plain text with key-value pairs

B Binary format

C HTML format

D Excel spreadsheet

JSON stores data as plain text using key-value pairs, making it easy to read and parse.

Which Java library is commonly used to parse JSON test data?

A TestNG

B JUnit

C Selenium WebDriver

D Jackson

Jackson is a popular Java library for parsing JSON into Java objects.

Why should test data be separated from test code?

A To make tests run faster

B To reduce file size

C To avoid hardcoding and improve maintainability

D To make tests more complex

Separating test data from code avoids hardcoding and makes tests easier to update and maintain.

What is a valid JSON data type?

A Function

B Array

C Class

D Pointer

JSON supports arrays as a data type to hold ordered lists of values.

What happens if JSON test data file is missing or corrupted during test execution?

A Test fails due to exception

B Test runs slower

C Test ignores data and continues

D Test passes automatically

If the JSON file is missing or corrupted, the test will fail because it cannot read required data.

Explain how to use JSON test data in a Selenium Java test.

Think about reading data from a file and using it in your test code.

Describe benefits of using JSON test data over hardcoded values.

Consider how changing data affects your test code.

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