cURL 和 HttpURLConnection - Post JSON Data

json post java curl httpurlconnection

2022-09-02 12:03:23

如何使用HttpURLConnection发布JSON数据？我正在尝试这个：

HttpURLConnection httpcon = (HttpURLConnection) ((new URL("a url").openConnection()));
httpcon.setDoOutput(true);
httpcon.setRequestProperty("Content-Type", "application/json");
httpcon.setRequestProperty("Accept", "application/json");
httpcon.setRequestMethod("POST");
httpcon.connect();

StringReader reader = new StringReader("{'value': 7.5}");
OutputStream os = httpcon.getOutputStream();

char[] buffer = new char[4096];
int bytes_read;    
while((bytes_read = reader.read(buffer)) != -1) {
    os.write(buffer, 0, bytes_read);// I am getting compilation error here
}
os.close();

我在第 14 行收到编译错误。

cURL 请求是：

curl -H "Accept: application/json" \
-H "Content-Type: application/json" \
-d "{'value': 7.5}" \
"a URL"

这是处理 cURL 请求的方法吗？任何信息都会对我很有帮助。

谢谢。

答案 1

OutputStream 希望使用字节，并且您正在为其传递字符。试试这个：

HttpURLConnection httpcon = (HttpURLConnection) ((new URL("a url").openConnection()));
httpcon.setDoOutput(true);
httpcon.setRequestProperty("Content-Type", "application/json");
httpcon.setRequestProperty("Accept", "application/json");
httpcon.setRequestMethod("POST");
httpcon.connect();

byte[] outputBytes = "{'value': 7.5}".getBytes("UTF-8");
OutputStream os = httpcon.getOutputStream();
os.write(outputBytes);

os.close();

答案 2

您可能希望使用 OutputStreamWriter 类。

final String toWriteOut = "{'value': 7.5}";
final OutputStreamWriter osw = new OutputStreamWriter(connection.getOutputStream());
osw.write(toWriteOut);
osw.close();