sepcific error page for HttpClientDownloaderTest to avoid test error when local port is available

webmagic-core/src/test/java/us/codecraft/webmagic/downloader/HttpClientDownloaderTest.java

@@ -26,6 +26,8 @@ import static org.junit.Assert.assertTrue;
  */
 public class HttpClientDownloaderTest {
 
+    public static final String PAGE_ALWAYS_NOT_EXISTS = "http://localhost:13421/404";
+
     @Ignore
     @Test
     public void testCookie() {
@@ -52,7 +54,7 @@ public class HttpClientDownloaderTest {
     public void testCycleTriedTimes() {
         HttpClientDownloader httpClientDownloader = new HttpClientDownloader();
         Task task = Site.me().setDomain("localhost").setCycleRetryTimes(5).toTask();
-        Request request = new Request("http://localhost/404");
+        Request request = new Request(PAGE_ALWAYS_NOT_EXISTS);
         Page page = httpClientDownloader.download(request, task);
         assertThat(page.getTargetRequests().size() > 0);
         assertThat((Integer) page.getTargetRequests().get(0).getExtra(Request.CYCLE_TRIED_TIMES)).isEqualTo(1);