HttpURLConnection删除在Android中不起作用

Question

我想从RESTful Webservice in Android删除一个项目。我的Webservice看起来像这样：

@DELETE
@Path("/schueler/{id}")
@Produces(MediaType.APPLICATION_JSON)
public void deleteSchueler(@PathParam("id") int id) {
    ManagementDAO.instance.deleteSchueler(id);
}

这里有一些Android代码。首先调用AsyncTask：

new AsyncDeleteSchueler(getApplicationContext()).execute("http://" + url.getText().toString() + ":8080/A07_Webservice/rest/ManagementService/schueler/" + Integer.parseInt(deleteId.getText().toString()));

以及此任务的代码：

public String putJSONToWebservice(String u) {
    int responseCode = 0;

    try {
        URL url = new URL(u);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();

        connection.setRequestMethod("DELETE");
        connection.setDoOutput(true);
        connection.setReadTimeout(10000);
        connection.setConnectTimeout(15000);
        connection.setRequestProperty("Content-Type", "application/json");
        connection.setRequestProperty("Accept", "application/json");

        connection.connect();
        responseCode = connection.getResponseCode();
    } catch(Exception ex) {
        ex.printStackTrace();
    }

    return Integer.toString(responseCode);
}

你知道为什么Delete method不起作用吗？ PUT，POST等工作正常，但这段代码没有。