Beginning Java 8 Language Features: Lambda Expressions, Inner Classes, Th reads, I/O, Collections,and Streams

// PersonExtSerializationTest.javapackage com.jdojo.io;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.ObjectOutputStream;public class PersonExtSerializationTest {        public static void main(String[] args) {                // Create three Person objects                PersonExt john = new PersonExt("John", "Male", 6.7);                PersonExt wally = new PersonExt("Wally", "Male", 5.7);                PersonExt katrina = new PersonExt("Katrina", "Female", 5.4);                // The output file                File fileObject = new File("personext.ser");                try (ObjectOutputStream oos = new ObjectOutputStream (                        new FileOutputStream(fileObject))) {                         ...