### Question:
LabelContainer { synchronized public int getSize() { return labelMap.size(); } protected  LabelContainer(); synchronized static LabelContainer getInstance(); synchronized void addLabel(String label); synchronized Integer getLabelID(String label); synchronized String getLabel(Integer labelID); synchronized int getSize();  }### Answer:
@Test public void testGetSize() { String label = "R3"; LabelContainer instance = new LabelContainer(); instance.addLabel(label); int expectedValue = 3; int result = instance.getSize(); Assert.assertEquals(expectedValue, result); }