Crete CachedSupplier

1 files changed, 39 insertions, 0 deletions

diff --git a/vespajlib/src/test/java/com/yahoo/lang/CachedSupplierTest.java b/vespajlib/src/test/java/com/yahoo/lang/CachedSupplierTest.java
new file mode 100644
index 00000000000..b0dc1262ebc
--- /dev/null
+++ b/vespajlib/src/test/java/com/yahoo/lang/CachedSupplierTest.java
@@ -0,0 +1,39 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.lang;
+
+import com.yahoo.test.ManualClock;
+import org.junit.Test;
+
+import java.time.Duration;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * @author freva
+ */
+public class CachedSupplierTest {
+
+    @Test
+    public void test() {
+        ManualClock clock = new ManualClock();
+        MutableInteger integer = new MutableInteger(0);
+        CachedSupplier<Integer> supplier = new CachedSupplier<>(() -> integer.add(1), Duration.ofMinutes(1), clock);
+
+        assertEquals(1, supplier.get().intValue());
+        assertEquals(1, supplier.get().intValue());
+
+        clock.advance(Duration.ofSeconds(30));
+        assertEquals(1, supplier.get().intValue());
+
+        clock.advance(Duration.ofSeconds(31));
+        assertEquals(2, supplier.get().intValue());
+        assertEquals(2, supplier.get().intValue());
+
+        supplier.refresh();
+        assertEquals(3, supplier.get().intValue());
+        assertEquals(3, supplier.get().intValue());
+
+        clock.advance(Duration.ofSeconds(61));
+        assertEquals(4, supplier.get().intValue());
+    }
+}