Java cURL和HttpURLConnection-发布JSON数据

如何使用HttpURLConnection发布JSON数据？我正在尝试：

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();

第14行出现编译错误

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

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谢谢。

OutputStream需要处理字节，您正在向其传递字符。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();

您可能希望使用OutputStreamWriter类

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您应该发布编译错误。是否不能以这种方式发送复杂的json对象？例如。。。“{”点：{”点：{“纬度”：40.8195085182092，“经度”：-73.75127574479318}，“描述”：“测试”}，{”点：{“纬度”：40.2195085182092，“经度”：-74.75127574479318}，“描述”：“测试2”}，“模式”：“行走”}。。。是我通过此方法发送的对象，我得到的HTTP响应代码为500。@CrowMagnumb您应该发布一个单独的问题。500表示服务器在处理您的请求时出现内部错误。好的，我已经这样做了，谢谢您的建议。与

OutputStream

相比，它有什么好处？

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