add switch example

Author: tobyweston

src/main/java/s4j/java/chapter13/Switch.java

@@ -0,0 +1,35 @@
+package s4j.java.chapter13;
+
+public class Switch {
+    public static void main(String... args) {
+        String month = "August";
+        String quarter;
+        switch (month) {
+            case "January":
+            case "February":
+            case "March":
+                quarter = "1st quarter";
+                break;
+            case "April":
+            case "May":
+            case "June":
+                quarter = "2nd quarter";
+                break;
+            case "July":
+            case "August":
+            case "September":
+                quarter = "3rd quarter";
+                break;
+            case "October":
+            case "November":
+            case "December":
+                quarter = "4th quarter";
+                break;
+            default:
+                quarter = "unknown quarter";
+                break;
+        }
+        System.out.println(quarter);
+    }
+
+}

src/main/scala/s4j/scala/chapter13/Switch.scala

@@ -0,0 +1,81 @@
+package s4j.scala.chapter13
+
+object BrokenSwitch extends App {
+
+  val month = "August"
+  var quarter = "???"
+  month match {
+    case "January"   =>
+    case "February"  =>
+    case "March"     => quarter = "1st quarter"
+    case "April"     =>
+    case "May"       =>
+    case "June"      => quarter = "2nd quarter"
+    case "July"      =>
+    case "August"    =>
+    case "September" => quarter = "3rd quarter"
+    case "October"   =>
+    case "November"  =>
+    case "December"  => quarter = "4th quarter"
+    case _           => quarter = "unknown quarter"
+  }
+  System.out.println(month + " is " + quarter)
+}
+
+object Switch extends App {
+  val month = "August"
+  var quarter = "???"
+
+  month match {
+    case "January"   => quarter = "1st quarter"
+    case "February"  => quarter = "1st quarter"
+    case "March"     => quarter = "1st quarter"
+    case "April"     => quarter = "2nd quarter"
+    case "May"       => quarter = "2nd quarter"
+    case "June"      => quarter = "2nd quarter"
+    case "July"      => quarter = "3nd quarter"
+    case "August"    => quarter = "3rd quarter"
+    case "September" => quarter = "3rd quarter"
+    case "October"   => quarter = "4th quarter"
+    case "November"  => quarter = "4th quarter"
+    case "December"  => quarter = "4th quarter"
+    case _           => quarter = "unknown quarter"
+  }
+  println(month + " is " + quarter)
+}
+
+object SwitchWithLessDuplication extends App {
+  val month = "August"
+  var quarter = "???"
+  month match {
+    case "January" | "February" | "March"    => quarter = "1st quarter"
+    case "April" | "May" | "June"            => quarter = "2nd quarter"
+    case "July" | "August" | "September"     => quarter = "3rd quarter"
+    case "October" | "November" | "December" => quarter = "4th quarter"
+    case _                                   => quarter = "unknown quarter"
+  }
+  println(month + " is " + quarter)
+}
+
+object SwitchExpression extends App {
+  val month = "August"
+  val quarter = month match {
+    case "January" | "February" | "March"    => "1st quarter"
+    case "April" | "May" | "June"            => "2nd quarter"
+    case "July" | "August" | "September"     => "3rd quarter"
+    case "October" | "November" | "December" => "4th quarter"
+    case _                                   => "unknown quarter"
+  }
+  println(month + " is " + quarter)
+}
+
+object SwitchExpressionInLine extends App {
+  val month = "August"
+  println(month + " is " + (month match {
+    case "January" | "February" | "March"    => "1st quarter"
+    case "April" | "May" | "June"            => "2nd quarter"
+    case "July" | "August" | "September"     => "3rd quarter"
+    case "October" | "November" | "December" => "4th quarter"
+    case _                                   => "unknown quarter"
+  }))
+}