Field definitions in test classes

Question

Consider the following test class:

public class MyTest extends extends EasyMockSupport {

    private static TestobjectFactory testobjectFactory = new TestobjectFactory();
    private static final Date DATE = testobjectFactory.createDate(2013, 0, 13, 01, 02, 03);
    private static final String CSV = "einCsv";

    @TestSubject
    private ClassToBeTested classUnderTest = new ClassToBeTested();

    @Mock
    private ClassToBeMocked myMock;

    @After
    public void tearDown() {
        verifyAll();
    }

    @Test
    public void myTest() throws Exception {
        replayAll();

        String outcome = classUnderTest.someMethod("", DATE);

        assertThat(outcome, is(""));
    }

    @Test
    public void anotherTest() throws Exception {
        expect(myMock.mockedMethod((String[]) anyObject())).andReturn(testobjectFactory.foo());

        replayAll();

        String outcome = classUnderTest.someMethod(CSV, DATE);

        assertTrue(outcome.contains("abc"));
    }

}

Questions:

• Why would you define CSV (or DATE) static final? Defining it final I agree as it's constant. But why static?

• Which fields are written in uppercase? private static final MY_FIELD; private final MY_FIELD; private static MY_FIELD;

• Wouldn't it be better to use a static TestobjectFactory?

Edit:

I already saw that post from the possible duplicate before. But the questions I wrote don't have an answer in there.