Useful Java Tips

1. String.join()
   When you need to concatenate collections or arrays with a delimiter, 'String.join()` makes the task simple and clean—similar to '.join' in Python.
   Example:

List words = Arrays.asList("Java", "Spring", "React");
String result = String.join(", ", words);
System.out.println(result); // Output: Java, Spring, React

Great for handling strings without manual loops or conditional checks.

2. 'var' in Java
   Java 10 introduced 'var' for compile-time type inference. Unlike Python’s dynamic typing, 'var' relies on the compiler to infer the type from the assignment.
   Example:
   var name = "Leetcode"; // inferred as a String

In Python,
x = 10 //int
x = "Hello" //now str
But Java’s 'var' is not like this— it’s type-safe.

Best Practices:
-> We can use 'var' when the type is obvious from the right hand side.
Example:
for (var entry : map.entrySet()) {
System.out.println(entry.getKey() + " -> " + entry.getValue());
}

-> Avoid using 'var' when the type is ambiguous, as it may hurt readability.

Not recommended
var data = getData(); //what kind of data type?