2.7.0版本getContextPath方法：
```
protected String getContextPath(URL url) {
        String contextPath = url.getPath();
        return contextPath.endsWith("/") ? contextPath.substring(0,contextPath.length()-1) : contextPath;
    }
```
无法将方法置入web容器中，退回2.6.5版本的方法：
```
protected String getContextPath(URL url) {
        int pos = url.getPath().lastIndexOf("/");
        return pos > 0 ? url.getPath().substring(0, pos) : "";
    }
```
使用正常，两个方法应该不等价的。
delayService.export();
        assertTrue(delayService.getExportedUrls().isEmpty());
        
        TimeUnit.MILLISECONDS.sleep(delayService.getDelay() + 300);
        assertThat(delayService.getExportedUrls(), hasSize(1));
    }
    @Test
    @Disabled("cannot pass in travis")
    public void testUnexport() throws Exception {
        System.setProperty(Constants.SHUTDOWN_WAIT_KEY, "0");
        try {
            service.export();
            service.unexport();
            Thread.sleep(1000);
            Mockito.verify(exporter, Mockito.atLeastOnce()).unexport();
        } finally {
            System.clearProperty(Constants.SHUTDOWN_TIMEOUT_KEY);
        }
    }
    @Test
    public void testInterfaceClass() throws Exception {
        ServiceConfig<Greeting> service = new ServiceConfig<Greeting>();
        service.setInterface(Greeting.class.getName());
        service.setRef(Mockito.mock(Greeting.class));
        assertThat(service.getInterfaceClass() == Greeting.class, is(true));
        service = new ServiceConfig<Greeting>();
        service.setRef(Mockito.mock(Greeting.class, withSettings().extraInterfaces(GenericService.class)));
        assertThat(service.getInterfaceClass() == GenericService.class, is(true));
    }
    @Test