在邮递员中发送请求时,得到以下输出:
{
"valid": false,
"reason": "taken",
"msg": "Username has already been taken",
"desc": "That username has been taken. Please choose another."
}
但是,当使用okhttp
进行编码时,出现编码问题,无法使用gson
将生成的json字符串转换为Java对象。
我有此代码:
public static void main(String[] args) throws Exception {
TwitterChecker checker = new TwitterChecker();
TwitterJson twitterJson = checker.checkUsername("dogster");
System.out.println(twitterJson.getValid()); //NPE
System.out.println(twitterJson.getReason());
System.out.println("Done");
}
public TwitterJson checkUsername(String username) throws Exception {
HttpUrl.Builder urlBuilder = HttpUrl.parse("https://twitter.com/users/username_available").newBuilder();
urlBuilder.addQueryParameter("username", username);
String url = urlBuilder.build().toString();
Request request = new Request.Builder()
.url(url)
.addHeader("Content-Type", "application/json; charset=utf-8")
.build();
OkHttpClient client = new OkHttpClient();
Call call = client.newCall(request);
Response response = call.execute();
System.out.println(response.body().string());
Gson gson = new Gson();
return gson.fromJson(
response.body().string(), new TypeToken<TwitterJson>() {
}.getType());
}
哪个打印此:
{"valid":false,"reason":"taken","msg":"\u0414\u0430\u043d\u043d\u043e\u0435 \u0438\u043c\u044f \u0443\u0436\u0435 \u0437\u0430\u043d\u044f\u0442\u043e","desc":"\u0414\u0430\u043d\u043d\u043e\u0435 \u0438\u043c\u044f \u0443\u0436\u0435 \u0437\u0430\u043d\u044f\u0442\u043e. \u041f\u043e\u0436\u0430\u043b\u0443\u0439\u0441\u0442\u0430, \u0432\u044b\u0431\u0435\u0440\u0438\u0442\u0435 \u0434\u0440\u0443\u0433\u043e\u0435."}
,然后在尝试访问NullPointerException
时抛出twitterJson
。调试器将该对象显示为null
。
TwitterJson:
@Generated("net.hexar.json2pojo")
@SuppressWarnings("unused")
public class TwitterJson {
@Expose
private String desc;
@Expose
private String msg;
@Expose
private String reason;
@Expose
private Boolean valid;
public String getDesc() {
return desc;
}
public String getMsg() {
return msg;
}
public String getReason() {
return reason;
}
public Boolean getValid() {
return valid;
}
...
如何解决okhttp的编码问题?
这是因为响应对象只能使用一次。 OKHTTP在他们的documentation中说。调用execute之后,您将两次调用响应对象。将response.body()。string()的结果存储到变量中,然后将其转换为GSON。
如果我要使用一个hello world示例...
private void testOkHttpClient() {
OkHttpClient httpClient = new OkHttpClient();
try {
Request request = new Request.Builder()
.url("https://www.google.com")
.build();
Call call = httpClient.newCall(request);
Response response = call.execute();
System.out.println("First time " + response.body().string()); // I get the response
System.out.println("Second time " + response.body().string()); // This will be empty
} catch (IOException e) {
e.printStackTrace();
}
}
之所以第二次为空,是因为响应对象只能使用一次。所以你要么
按原样返回响应。不要做sysOut
System.out.println(response.body().string()); // Instead of doing a sysOut return the value.
或
将响应的值存储到JSON,然后将其转换为GSON,然后返回值。
EDIT:关于Unicode字符。事实证明,由于我所在的地区不是一个讲英语的国家,所以我接受的json也不是英语。我添加了此标题:
.addHeader("Accept-Language", Locale.US.getLanguage())
关于解决该问题的请求。