How to Use If/Else Logic with Streams in Java 8

How can I represent if/else conditions using Java 8 Streams?

List<String> names = Arrays.asList("Alice", "Bob", "Charlie");

names.stream()
     .filter(name -> name.startsWith("A"))
     .map(name -> name + " starts with A")
     .forEach(System.out::println);

names.stream()
     .filter(name -> !name.startsWith("A"))
     .map(name -> name + " does not start with A")
     .forEach(System.out::println);

In Java 8, you can elegantly handle if/else conditions using Streams through filtering, mapping, and conditional operations. This allows you to write more functional, readable code instead of traditional control structures.

List<String> names = Arrays.asList("Alice", "Bob", "Charlie");

names.stream()
     .map(name -> name.startsWith("A") ? name + " starts with A" : name + " does not start with A")
     .forEach(System.out::println);

Causes

• The traditional if/else structures can lead to more verbose code.
• Streams provide a way to express data processing in a functional style.

Solutions

• Use the `filter()` method to apply conditions that would normally be handled by an if/else statement.
• Utilize the `map()` method to transform the data based on the evaluated conditions.

Mistake: Using regular for loops instead of streams for conditional processing.

Solution: Leverage stream operations like filter and map to simplify your code.

Mistake: Not handling null values in streams, leading to NullPointerExceptions.

Solution: Use Optional or .filter() to avoid null issues.