@Test
public void testPropertyLoader() {

	PropertyLoader.getInstance().init("TraverserTests.properties");
	Assert.assertNotNull(PropertyLoader.getInstance().getProperty("FileTraverser.basePath"));
	Assert.assertNotNull(PropertyLoader.getInstance().getProperty("HDFSTraverser.basePath"));
	PropertyLoader.getInstance().setProperty("test", "test1");
	Assert.assertEquals(PropertyLoader.getInstance().getProperty("test"), "test1");
	System.setProperty("test1", "test2");
	Assert.assertEquals(PropertyLoader.getInstance().getProperty("test1"), "test2");
	Assert.assertNull(PropertyLoader.getInstance().getProperty("test2"));
	
	try {
		PropertyLoader.getInstance().init(null);
		Assert.fail();
	} catch(IllegalArgumentException e) {
	}
	try {
		PropertyLoader.getInstance().init("abc");
		Assert.fail();
	} catch(Exception e) {
	}
}