Create singleton CloudNames for known clouds

2 files changed, 33 insertions, 6 deletions

diff --git a/config-provisioning/src/main/java/com/yahoo/config/provision/CloudName.java b/config-provisioning/src/main/java/com/yahoo/config/provision/CloudName.java
index ba262136abe..e1d7afdc9f0 100644
--- a/config-provisioning/src/main/java/com/yahoo/config/provision/CloudName.java
+++ b/config-provisioning/src/main/java/com/yahoo/config/provision/CloudName.java
@@ -3,7 +3,6 @@ package com.yahoo.config.provision;
 
 import ai.vespa.validation.PatternedStringWrapper;
 
-import java.util.Objects;
 import java.util.regex.Pattern;
 
 /**
@@ -14,17 +13,23 @@ import java.util.regex.Pattern;
 public class CloudName extends PatternedStringWrapper<CloudName> {
 
     private static final Pattern pattern = Pattern.compile("[a-z]([a-z0-9-]*[a-z0-9])*");
-    public static final CloudName AWS = from("aws");
-    public static final CloudName GCP = from("gcp");
-    public static final CloudName DEFAULT = from("default");
-    public static final CloudName YAHOO = from("yahoo");
+    public static final CloudName AWS = new CloudName("aws");
+    public static final CloudName GCP = new CloudName("gcp");
+    public static final CloudName DEFAULT = new CloudName("default");
+    public static final CloudName YAHOO = new CloudName("yahoo");
 
     private CloudName(String cloud) {
         super(cloud, pattern, "cloud name");
     }
 
     public static CloudName from(String cloud) {
-        return new CloudName(cloud);
+        return switch (cloud) {
+            case "aws" -> AWS;
+            case "gcp" -> GCP;
+            case "default" -> DEFAULT;
+            case "yahoo" -> YAHOO;
+            default -> new CloudName(cloud);
+        };
     }
 
 }
diff --git a/config-provisioning/src/test/java/com/yahoo/config/provision/CloudNameTest.java b/config-provisioning/src/test/java/com/yahoo/config/provision/CloudNameTest.java
new file mode 100644
index 00000000000..b030233d459
--- /dev/null
+++ b/config-provisioning/src/test/java/com/yahoo/config/provision/CloudNameTest.java
@@ -0,0 +1,22 @@
+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.provision;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+/**
+ * @author freva
+ */
+class CloudNameTest {
+
+    @Test
+    void returns_same_instance_for_known_clouds() {
+        assertSame(CloudName.from("aws"), CloudName.AWS);
+        assertSame(CloudName.from("gcp"), CloudName.GCP);
+        assertSame(CloudName.from("default"), CloudName.DEFAULT);
+        assertSame(CloudName.from("yahoo"), CloudName.YAHOO);
+        assertThrows(IllegalArgumentException.class, () -> CloudName.from("aWs")); // Must be lower case
+    }
+}