How can I filter data using Java Streams?

How can I filter data using Java Streams?

You can use the filter method in Java Streams to filter data based on a condition. For example, if you have a list of integers and want to filter out even numbers, you can do it like this: list.stream().filter(n -> n % 2 != 0).collect(Collectors.toList());

Can you explain the lambda expression used in the filter method?

Sure! The lambda expression n -> n % 2 != 0 is a shorthand for implementing the Predicate interface. It checks if a number n is odd by returning true if n is not divisible by 2.

What if I want to filter a list of objects instead of integers?

You can still use the filter method. For example, if you have a list of Person objects and want to filter by age, you can do: people.stream().filter(p -> p.getAge() > 18).collect(Collectors.toList());

Are there any performance considerations when using streams?

Yes, while streams can make your code more readable, they may have performance overhead due to their internal processing. It's best to use them for larger datasets where readability is a priority.