All matching elements & iterating collections

Use findElements to work with 0..N elements safely and loop over them.

Concept

In real web apps, you often have multiple elements that share the same locator:

A list of filter buttons.
A group of error messages.
Multiple rows in a table.

Selenium gives you two different methods:

`findElement(...)` – singular

Returns the first matching element.
Throws NoSuchElementException if nothing matches.

`findElements(...)` – plural

Returns a List of WebElement for all matches.
If nothing matches, it returns an empty list, not null and not an exception.

Mental Model

findElement → "Give me one element or fail."
findElements → "Give me all elements, or an empty list if none."

Why findElements is Important

Lets you:

Loop over a collection of elements (e.g., all filter chips).
Safely check if something exists without using try/catch.
Implement logic like "click only the filter with text X" or "validate that no warning is displayed."

It's the standard way to handle 0..N elements in Selenium.

Best Practice Notes

Use findElements whenever you are not 100% sure the elements will be present.
Always check .isEmpty() on lists when you want to safely test presence/absence.
When searching for an item by text, get the list once, then loop through it.

Interactive Practice

In this practice, you will work with a row of filter buttons that all share the same class.

Filter Buttons Demo

Active filters: None

Click the filter buttons directly to see them toggle. Use Selenium's findElements to interact with all buttons!

Page Elements

A group of filter buttons: Java, Python, JavaScript, C#
Each button has: class="lesson6-filter-btn"
A text area showing the active state:
- Label: "Active filters: None" (initially)
- When you click a filter, this label updates (e.g., "Active filters: Java")
Optional warning area:
- When certain conditions occur (e.g., invalid combination), a message might appear with: class="warning-msg"

How You'd Interact Manually

Look at the row of buttons: Java, Python, JavaScript, C#.
Click Java and observe:
- The filter toggles state (e.g., highlighted).
- The text "Active filters" updates to include Java.
Optionally check if any warning message appeared on the page.

What Selenium Will Do

Use findElements to:

Get all buttons with the class .lesson6-filter-btn.
Loop through them and find the one whose visible text is "Java".
Click it when found.
Then use findElements again to safely check if any .warning-msg elements exist.

Java Code Example

FindElementsExample.java

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List<WebElement> filters = driver.findElements(By.cssSelector(".lesson6-filter-btn"));

for (WebElement filter : filters) {
    String text = filter.getText().trim();
    if ("Java".equals(text)) {
        filter.click();
        break;
    }
}

List<WebElement> warnings = driver.findElements(By.cssSelector(".warning-msg"));
if (warnings.isEmpty()) {
    System.out.println("No warnings found (Safe check)");
}

driver.quit();

Code Breakdown

List<WebElement> filters = driver.findElements(By.cssSelector(".lesson6-filter-btn"));: Uses findElements (plural) to get all buttons with class lesson6-filter-btn. If none exist, filters will be an empty list, not null.
for (WebElement filter : filters) {: Starts a for-each loop to inspect each button in the collection.
String text = filter.getText().trim();: Reads the visible text of the button and trims spaces. This is how we decide which filter is the one we want.
if ("Java".equals(text)) { filter.click(); break; }: Checks if the button's text is exactly "Java". If yes, we click it and then break to stop the loop (no need to continue).
List<WebElement> warnings = driver.findElements(By.cssSelector(".warning-msg"));: Another findElements call to search for any warning messages on the page. Again, this returns an empty list if nothing matches.
if (warnings.isEmpty()) { System.out.println("No warnings found (Safe check)"); }: Uses .isEmpty() to do a safe presence check. No exceptions, regardless of whether warnings exist or not.
driver.quit();: Closes the browser and ends the WebDriver session cleanly.

Pro Tip

Use findElements for presence checks

It's better to check .isEmpty() on a list than to catch NoSuchElementException from findElement.

Avoid repeated calls

Get the list once, then loop and decide what to do inside the loop (click, assert, collect data).

Prefer clear matching logic

When searching by text, always normalize (e.g., .trim()) so small formatting changes don't break your tests.

All matching elements & iterating collections

Concept

findElement(...) – singular

findElements(...) – plural

Mental Model

Why findElements is Important

Best Practice Notes

Interactive Practice

Filter Buttons Demo

Page Elements

How You'd Interact Manually

What Selenium Will Do

Java Code Example

Code Breakdown

Pro Tip

Use findElements for presence checks

Avoid repeated calls

Prefer clear matching logic

All matching elements & iterating collections

Concept

findElement(...) – singular

findElements(...) – plural

Mental Model

Why findElements is Important

Best Practice Notes

Interactive Practice

Filter Buttons Demo

Page Elements

How You'd Interact Manually

What Selenium Will Do

Java Code Example

Code Breakdown

Pro Tip

Use findElements for presence checks

Avoid repeated calls

Prefer clear matching logic

`findElement(...)` – singular

`findElements(...)` – plural

`findElement(...)` – singular

`findElements(...)` – plural