jMockit在模拟对象中意外执行实际方法

Question

我有一个测试代码（使用jmockit 1.8）：

public class BasicTest {
    ...
    @Mocked("evaluateAlternateTerms")
    WMSTK_BLT_Services wmstkBltServices;    
    @Before
    public void setUp() {...}

    @Test
    public void testAlternativeDatesCalculationException() throws Throwable {
        new Expectations() {{
            withSameInstance(capacityService);
            withSameInstance(buchungs);
            Deencapsulation.invoke(wmstkBltServices, "evaluateAlternateTerms", CapacityService.class, List.class);
            result = new KVWSException(new ErrorCode(1)) {
                public String getMessage() {
                    return "TEST";
                }
            };
        }};
        KapazitaetAendernResponse result = alternativeDates(capacityService, buchungs);

        assertThat(result.getFehlercode(), is((short) 9999));
        assertThat(result.getFehlertext(), is("TEST"));
    }

我试图使用模拟方法＆＃34; evaluateAlternateTerms＆＃34;，但它发送错误：

java.lang.NullPointerException
    at com.tsystems.kvws.WMSTK_BLT_Services.evaluateAlternateTerms(WMSTK_BLT_Services.java:87)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.tsystems.kvws.tests.wmstkKapazitaetsservices.alternativeDates.BasicTest$1.(BasicTest.java:81)
    at com.tsystems.kvws.tests.wmstkKapazitaetsservices.alternativeDates.BasicTest.testAlternativeDatesCalculationException(BasicTest.java:78)

为什么？？我做了模拟，它不能去：

evaluateAlternateTerms(WMSTK_BLT_Services.java:87)

P.S。这是alternativeDates方法：

private KapazitaetAendernResponse alternativeDates(CapacityService capacityService, List kapResBuchungs) throws Throwable {
        return (KapazitaetAendernResponse) PrivateAccessor.invoke(new WmstkKapazitaetsservices(),
                "alternativeDates", new Class[] {CapacityService.class, List.class}, 
                new Object[] {capacityService, kapResBuchungs});
    }

提前致谢！