如何在Java中通过HTTP发布JSON数据？

Question

我是JSON新手，正在开发Coinbase APISee here

所以我试图通过HTTP发布这些数据：

{
  "transaction": {
    "to": "user1@example.com",
    "amount": "1.234",
    "notes": "Sample transaction for you"
  }
}

在Java中我该怎么做

我知道如何创建一个程序来GETa响应，但不知道如何POSTa请求

以下是我的回应程序：

import java.io.IOException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;

import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Hex;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpRequestBase;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;

import com.coinbase.api.Coinbase;
import com.coinbase.api.CoinbaseBuilder;

public class CoinbaseExample {

    static String API_KEY = "My API KEY";

    static String API_SECRET = "MY API SECRET";

    public static String getHttp(String url, String body)
            throws InvalidKeyException, NoSuchAlgorithmException,
            ClientProtocolException, IOException {

        String nonce = String.valueOf(System.currentTimeMillis());
        String message = nonce + url + (body != null ? body : "");

        Mac mac = Mac.getInstance("HmacSHA256");
        mac.init(new SecretKeySpec(API_SECRET.getBytes(), "HmacSHA256"));
        String signature = new String(Hex.encodeHex(mac.doFinal(message.getBytes())));

        HttpRequestBase request;
        if (body == null || body.length() == 0)
            request = new HttpGet(url);
        else {
            HttpPost post = new HttpPost(url);
            post.setEntity(new StringEntity(body));
            request = post;
        }
        request.setHeader("ACCESS_KEY", API_KEY);
        request.setHeader("ACCESS_SIGNATURE", signature);
        request.setHeader("ACCESS_NONCE", nonce);

        HttpClient httpClient = HttpClientBuilder.create().build();
        HttpResponse response = httpClient.execute(request);

        HttpEntity entity = response.getEntity();
        if (entity != null)
            return EntityUtils.toString(entity);
        return null;
    }

}

如何创建类似于Post请求的程序

Answer 1

试试这个

String url = "http://yoururl.com";
URL obj = new URL(url);
HttpsURLConnection con = (HttpsURLConnection) obj.openConnection();

//add reuqest header
con.setRequestMethod("POST");
con.setRequestProperty("User-Agent", USER_AGENT);
con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");

String urlParameters = "sn=C02G8416DRJM&cn=&locale=&caller=&num=12345";

// Send post request
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(urlParameters);
wr.flush();
wr.close();

int responseCode = con.getResponseCode();
System.out.println("\nSending 'POST' request to URL : " + url);
System.out.println("Post parameters : " + urlParameters);
System.out.println("Response Code : " + responseCode);

BufferedReader in = new BufferedReader(
        new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();

while ((inputLine = in.readLine()) != null) {
    response.append(inputLine);
}
in.close();

//print result
System.out.println(response.toString());