TP-1222: Make getInstance() thread-safe with double-checked locking (#49

)
AvanzaBank · Sep 5, 2022 · b022171 · b022171
1 parent fe7c051
commit b022171
Showing 1 changed file with 7 additions and 3 deletions.
diff --git a/gs-test-core/src/main/java/com/avanza/gs/test/JVMGlobalGigaSpacesManager.java b/gs-test-core/src/main/java/com/avanza/gs/test/JVMGlobalGigaSpacesManager.java
@@ -22,12 +22,16 @@
  */
 public final class JVMGlobalGigaSpacesManager {
 
-	private static InMemoryGigaSpacesManager instance;
+	private static volatile InMemoryGigaSpacesManager instance;
 
 	private static InMemoryGigaSpacesManager getInstance() {
 		if (instance == null) {
-			instance = new InMemoryGigaSpacesManager();
-			Runtime.getRuntime().addShutdownHook(new Thread(() -> instance.close()));
+			synchronized (JVMGlobalGigaSpacesManager.class) {
+				if (instance == null) {
+					instance = new InMemoryGigaSpacesManager();
+					Runtime.getRuntime().addShutdownHook(new Thread(() -> instance.close()));
+				}
+			}
 		}
 		return instance;
 	}