Here are some of the key features and changes introduced in Java 7:

1. Try-with-Resources: The try-with-resources statement simplifies resource management by automatically closing resources like streams, files, and database connections at the end of a try block. This helps in reducing resource leaks and simplifying code.

   Example:

   javaCopy code

   try (InputStream is = new FileInputStream("file.txt")) {
// Code that reads from is
} catch (IOException e) {
// Exception handling
}


2. Diamond Operator: The diamond operator (<>) allows you to omit redundant type information when creating instances of generic classes. It enhances code readability and reduces verbosity.

   Example:

   javaCopy code

   List<String> list = new ArrayList<>();


3. Strings in Switch: Java 7 introduced the ability to use strings in the switch statement. Prior to this, only integral types (e.g., int, char) were allowed.

   Example:

   javaCopy code

   String day = "Monday";
switch (day) {
case "Monday":
// Code for Monday
break;
case "Tuesday":
// Code for Tuesday
break;
// ...
default:
// Code for other days
}


4. Improved Type Inference: The Java 7 compiler was enhanced to provide better type inference in certain situations, reducing the need for explicit type declarations.

5. Fork/Join Framework: Java 7 introduced the Fork/Join framework, which simplifies parallel programming by providing a way to divide tasks among multiple threads and recombine their results.

6. NIO.2 (New I/O): The java.nio package was enhanced with new features, including the ability to perform asynchronous I/O operations, support for file system attributes, and improved file handling.

7. Automatic Closure of Resources: Java 7 added support for automatic resource management using the try-with-resources statement, which simplifies the closing of resources like streams and files.

8. Suppressed Exceptions: Java 7 introduced the concept of suppressed exceptions, which allows secondary exceptions to be associated with the primary exception, providing more context in error handling.

9. Decimal Literals: Java 7 allowed the use of underscores (_) in numeric literals, improving the readability of large numbers.

   Example:

   javaCopy code

   long billion = 1_000_000_000;


10. G1 Garbage Collector: Java 7 introduced the Garbage First (G1) Garbage Collector as an alternative to the older garbage collectors (such as CMS and Parallel).