Java http请求GET在浏览器中正常工作时导致超时异常

Question

我在Java 中一直在玩Http，我遇到了一个奇怪的问题。下面是一段执行GET方法的代码：

OkHttpClient client = new OkHttpClient();
client.setConnectTimeout(100, TimeUnit.SECONDS);
client.setReadTimeout(100, TimeUnit.SECONDS);
Response response = null;
Request request = new Request.Builder()
        .url("https://www.celebritycruises.com/")
        .get()
        .build();
try {
    response = client.newCall(request).execute();
    System.out.println(response.code());
} catch (IOException e) {
    e.printStackTrace();
} 

所以有一些网站（比如Builder 中提供的那个导致：

java.net.SocketTimeoutException: timeout
at okio.Okio$3.newTimeoutException(Okio.java:207)
at okio.AsyncTimeout.exit(AsyncTimeout.java:261)
at okio.AsyncTimeout$2.read(AsyncTimeout.java:215)
[...]
Caused by: java.net.SocketTimeoutException: Read timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.socketRead(SocketInputStream.java:116)
at java.net.SocketInputStream.read(SocketInputStream.java:171)
at java.net.SocketInputStream.read(SocketInputStream.java:141)
at sun.security.ssl.InputRecord.readFully(InputRecord.java:465)
at sun.security.ssl.InputRecord.read(InputRecord.java:503)
at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:983)
at sun.security.ssl.SSLSocketImpl.readDataRecord(SSLSocketImpl.java:940)

at sun.security.ssl.AppInputStream.read(AppInputStream.java:105)
at okio.Okio$2.read(Okio.java:139)
at okio.AsyncTimeout$2.read(AsyncTimeout.java:211)
... 38 more

我不明白的是：为什么这在浏览器中可以正常工作？我已经为100seconds 设置了timeouts。我也尝试过使用其他 HttpClient，但结果相同（我相信他们内心深处无论如何都使用相同的类）。谁能告诉我问题出在哪里？

编辑

我尝试了wget - 有效，保存了一些 HTML 内容。 curl 返回：(52) Empty reply from server

Answer 1

您必须在请求中使用用户代理。这有效：

Request request = new Request.Builder().url("https://www.celebritycruises.com/").header("User-Agent", "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0").build();