package com.baeldung.mapdb; import org.jetbrains.annotations.NotNull; import org.junit.Test; import org.mapdb.*; import java.io.IOException; import static junit.framework.Assert.assertEquals; public class HTreeMapUnitTest { @Test public void givenValidDB_whenHTreeMapAddedToAndRetrieved_CheckedRetrievalCorrect() { DB db = DBMaker.memoryDB().make(); HTreeMap hTreeMap = db .hashMap("myTreMap") .keySerializer(Serializer.STRING) .valueSerializer(Serializer.STRING) .create(); hTreeMap.put("key1", "value1"); hTreeMap.put("key2", "value2"); assertEquals(2, hTreeMap.size()); //add another value with the same key hTreeMap.put("key1", "value3"); assertEquals(2, hTreeMap.size()); assertEquals("value3", hTreeMap.get("key1")); } }