Question

我正在尝试使用HTTP从Google趋势中获取JSON响应。这是我的代码段：

public class TestClass {
    public static void main(String[] args) throws Exception{

    String address = "https://trends.google.com/trends/api/explore?hl=en-US&tz=240&req={\"comparisonItem\":[{\"keyword\":\"Miley\",\"geo\":\"US\",\"time\":\"2012-01-01 2014-01-01\"},{\"keyword\":\"Hannah Montana\",\"geo\":\"US\",\"time\":\"2012-01-01 2014-01-01\"}],\"category\":0,\"property\":\"\"}";

    URL url = new URL(address);

    HttpURLConnection con = (HttpURLConnection) url.openConnection();

    con.setRequestMethod("GET");

    int responseCode = con.getResponseCode();

    System.out.println("URL is "+address);

    System.out.println("Response code is " + responseCode); }
}

这是输出：

URL is https://trends.google.com/trends/api/explore?hl=en-US&tz=240&req={"comparisonItem":[{"keyword":"Miley","geo":"US","time":"2012-01-01 2014-01-01"},{"keyword":"Hannah Montana","geo":"US","time":"2012-01-01 2014-01-01"}],"category":0,"property":""}

Response code is 400

如果我直接在浏览器中输入网址，Google会给我一个没有问题的JSON文件。但是，如果我尝试使用Java访问该URL，则会收到错误的请求。我怎么解决这个问题？提前谢谢。

Answer 1

您需要URL对您的URL的查询字符串部分进行编码。查看this question/answer了解实现此目的的一些方法。

Answer 2

我解决了你的问题。我建议在apache http api上建立http-request。

private static final HttpRequest<String> REQUEST =
        HttpRequestBuilder.createGet("https://trends.google.com/trends/api/explore", String.class)
                .addDefaultRequestParameter("hl", "en-US")
                .addDefaultRequestParameter("tz", "240")
                .responseDeserializer(ResponseDeserializer.ignorableDeserializer())
                .build();

public void send() {
    ResponseHandler<String> responseHandler = REQUEST.execute("req", "{\"comparisonItem\":[{\"keyword\":\"Miley\",\"geo\":\"US\",\"time\":\"2012-01-01 2014-01-01\"},{\"keyword\":\"Hannah Montana\",\"geo\":\"US\",\"time\":\"2012-01-01 2014-01-01\"}],\"category\":0,\"property\":\"\"}");
    System.out.println(responseHandler.getStatusCode());
    responseHandler.ifHasContent(System.out::println);
}

代码打印响应代码200和浏览器获得的响应正文。

（Java）HTTP GET请求不断获得400响应代码，尽管链接在浏览器

2 个答案: