@Test
public void testGetKeyByValue() {

    HashMap<String, String> map = new HashMap<>();
    map.put("key1", "value1");
    map.put("key2", "value2");
    map.put("key3", "value3");
    assertEquals("key1", Utils.getKeyByValue(map, "value1"));
    assertEquals("key2", Utils.getKeyByValue(map, "value2"));
    assertEquals("key3", Utils.getKeyByValue(map, "value3"));
}