BAEL-4663: Whats new in Java 15

michael-pratt · michael-pratt · commit 8b3a092bc829 · 2020-11-11T14:51:36.000-07:00
diff --git a/core-java-modules/core-java-15/src/main/java/whatsnew/records/Person.java b/core-java-modules/core-java-15/src/main/java/whatsnew/records/Person.java
@@ -0,0 +1,16 @@
+package whatsnew.records;
+
+/**
+ * Java record with a header indicating 2 fields.
+ */
+public record Person(String name, int age) {
+
+    /**
+     * Public constructor that does some basic validation.
+     */
+    public Person {
+        if (age < 0) {
+            throw new IllegalArgumentException("Age cannot be negative");
+        }
+    }
+}
diff --git a/core-java-modules/core-java-15/src/main/java/whatsnew/sealedclasses/Employee.java b/core-java-modules/core-java-15/src/main/java/whatsnew/sealedclasses/Employee.java
@@ -0,0 +1,13 @@
+package whatsnew.sealedclasses;
+
+import java.util.Date;
+
+public non-sealed class Employee extends Person {
+
+    public Date getHiredDate()
+    {
+        return new Date();
+    }
+
+
+}
diff --git a/core-java-modules/core-java-15/src/main/java/whatsnew/sealedclasses/Manager.java b/core-java-modules/core-java-15/src/main/java/whatsnew/sealedclasses/Manager.java
@@ -0,0 +1,4 @@
+package whatsnew.sealedclasses;
+
+public final class Manager extends Person {
+}
diff --git a/core-java-modules/core-java-15/src/main/java/whatsnew/sealedclasses/Person.java b/core-java-modules/core-java-15/src/main/java/whatsnew/sealedclasses/Person.java
@@ -0,0 +1,25 @@
+package whatsnew.sealedclasses;
+
+import java.util.Date;
+
+public sealed class Person permits Employee, Manager
+{
+    /**
+     * Demonstration of pattern matching for instanceof
+     *
+     * @param person A Person object
+     * @return
+     */
+    public static void patternMatchingDemo(Person person)
+    {
+        if(person instanceof Employee employee)
+        {
+            Date hiredDate = employee.getHiredDate();
+        }
+
+        if(person instanceof Employee employee && employee.getHiredDate() != null)
+        {
+            Date hiredDate = employee.getHiredDate();
+        }
+    }
+}

-Original file line number
+Diff line change
@@ @@ -0,0 +1,4 @@ @@
 +package whatsnew.sealedclasses;
++
 +public final class Manager extends Person {
 +}