Class TryWithResourcesExamples

java.lang.Object
net.jrodolfo.java_evolution.java09.TryWithResourcesExamples
public class TryWithResourcesExamples extends Object
Demonstrates the Java 9 try-with-resources improvement.

Java 7 introduced try-with-resources, but a resource usually had to be declared inside the try (...) block. When a resource was already stored in a final or effectively final variable, code often repeated the variable just to satisfy the syntax.

Java 9 made it possible to use an existing final or effectively final resource variable directly in the resource list.

  • Constructor Details

    • TryWithResourcesExamples

      public TryWithResourcesExamples()

  • Method Details

    • readFirstLine

      public String readFirstLine(BufferedReader reader) throws IOException
      Reads the first line and closes the provided reader using the Java 9 try-with-resources style.
      Parameters:
      reader - an effectively final resource created before the try block
      Returns:
      the first line from the reader
      Throws:
      IOException - when reading fails