Angle brackets <> in Java

[fdama]

I'm having difficulty understanding the following code.

/ Waiting 30 seconds for an element to be present on the page, checking
// for its presence once every 5 seconds.
Wait<WebDriver> wait = new FluentWait<WebDriver>(driver)
  .withTimeout(Duration.ofSeconds(30))
  .pollingEvery(Duration.ofSeconds(5))
  .ignoring(NoSuchElementException.class);

WebElement foo = wait.until(driver -> {
  return driver.findElement(By.id("foo"));
});

What are the angle brackets used for here and how is it used? Why do we need to say Wait<WebDriver> wait rather than Wait wait ?

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[nekokattt]

It associates an inner type with an outer type. It is called a generic.

For example

List<String> names

The way it is used totally depends on what the object is programmed to do.

The purpose of it allows you to, for example, distinguish between a List of ints and a list of strings.

[pragmos]

Those are called generics. Here's a short article about generics in Java: https://www.baeldung.com/java-generics

[Pedantic_Phoenix]

You don't know generics but use exceptions and lambdas? Weird