pattern matching in java 14

JavaZakariae · JavaZakariae · commit b0536714798b · 2020-08-16T16:27:58.000+02:00
instanceof operator
diff --git a/pom.xml b/pom.xml
@@ -13,8 +13,10 @@
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
                 <configuration>
-                    <source>13</source>
-                    <target>13</target>
+                    <compilerArgument>--enable-preview</compilerArgument>
+                    <source>14</source>
+                    <target>14</target>
+                    <compilerArgs>--enable-preview</compilerArgs>
                 </configuration>
             </plugin>
         </plugins>
diff --git a/src/main/java/challenge21_30/Challenge_23.java b/src/main/java/challenge21_30/Challenge_23.java
@@ -33,10 +33,10 @@ public static void main( String[] args ) {
     private <R extends WeekDay, T > T getUsingSwitchCase(R weekDay) {
         var t = switch((WeekDay)weekDay){
             case MONDAY -> (T) Integer.valueOf(4);
-            case TUESDAY, WEDNESDAY, THURSDAY -> {
-                System.out.println("Every day is beer day for homer");
-                break  (Integer.valueOf(129) == 129 ? 5 : 7);
-            }
+//            case TUESDAY, WEDNESDAY, THURSDAY -> {
+//                System.out.println("Every day is beer day for homer");
+//                break  (Integer.valueOf(129) == 129 ? 5 : 7);
+//            }
             case FRIDAY -> (T) Double.valueOf(4);
             case SATURDAY, SUNDAY -> (T) (Object) "6" == new String("6") ? 2 : 4;
             default -> new IllegalStateException("Non existent day.");
diff --git a/src/main/java/others/youtube/BeyondJava8.java b/src/main/java/others/youtube/BeyondJava8.java
@@ -8,15 +8,53 @@
 /**
  * Life Beyond Java 8, by Trisha Gee / JetBrains Technology Day for Java (2020)
  * https://www.youtube.com/watch?v=gKestt55Q4M
+ * @todo java 13 and above
  */
 public class BeyondJava8 {
 
     public static void main( String[] args ) {
         //unmodifiableList();
         //unmodifiableMap();
         //collectToUnmodifiableList();
-        predicateNot();
+        //predicateNot();
+        //newSwitchStatement(new Random().nextInt());
+        //textBlocks();
+        Person p1 = new Employee("zaki");
+        instanceOfInJava14(p1);
+    }
+
+    private static void instanceOfInJava14(Person person) {
+
+        if (person instanceof Employee)
+        {
+            Employee employee = ((Employee) person);
+            System.out.println("employee.getEmployeeName() = " + employee.getEmployeeName());
+        }
+        //in Java 14, we can write the above code as follows
+
+        if (person instanceof Employee employee)
+        {
+            System.out.println("employee.getEmployeeName() = " + employee.getEmployeeName());
+        }
+    }
 
+    //java 13, for html, sql queries, json ......
+    private static void textBlocks() {
+        String multiLinesText =
+        """
+            Hello Brother, I'm using Java14;
+        """;
+        System.out.println("multiLinesText = " + multiLinesText);
+    }
+
+    // the new switch syntax
+    private static void newSwitchStatement(int i) {
+        String value = switch (i){
+            case 0 -> "0";
+            case 1, 2 -> "1";
+            default -> "NOT in [0-2]";
+        };
+        System.out.println("value = " + value);
     }
 
     private static void predicateNot() {
@@ -53,5 +91,32 @@ public static void unmodifiableList(){
         List<String> stringList2 = List.of("A", "B");
         stringList2.set(0, "C");
     }
+}
+
+
+class Person{
+    String name;
+
+    public Person(String name) {
+        this.name = name;
+    }
+
+    @Override
+    public String toString() {
+        return "Person{" +
+                "name='" + name + '\'' +
+                '}';
+    }
+}
+
+class Employee extends Person{
+    public Employee(String name) {
+        super(name);
+    }
+    public String getEmployeeName(){
+        return "Employee{" +
+                "name='" + this.name + '\'' +
+                '}';
+    }
 
 }
diff --git a/src/main/java/others/youtube/LetsGetLazy.java b/src/main/java/others/youtube/LetsGetLazy.java
@@ -0,0 +1,12 @@
+package others.youtube;
+
+/**
+ * Let's Get Lazy, by Venkat Subramaniam / JetBrains Technology Day for Java (2020)
+ * https://www.youtube.com/watch?v=PICHx2at46s
+ */
+public class LetsGetLazy {
+
+    public static void main( String[] args ) {
+        System.out.println();
+    }
+}
