I am using Ubuntu Server 12.04. My *.conf file:

# Enable RPC

# Uncomment to allow localhost to use RPC

# RPC information

# Mining is initially disabled
# gen=0

Java RPCClient that I use:

import java.io.IOException;
import java.util.Arrays;
import java.util.List;
import java.util.UUID;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.ParseException;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;

public class RPCClient {

    private static final String COMMAND_GET_BALANCE = "getbalance";
    private static final String COMMAND_GET_INFO = "getinfo";
    private static final String COMMAND_GET_NEW_ADDRESS = "getnewaddress";

    private JSONObject invokeRPC(String id, String method, List<String> params) {

//      CloseableHttpClient httpclient = HttpClientBuilder.create().build();
//      httpclient.getCredentialsProvider();
        DefaultHttpClient httpclient = new DefaultHttpClient();

        JSONObject json = new JSONObject();
        json.put("id", id);
        json.put("method", method);
        if (null != params) {
            JSONArray array = new JSONArray();
            json.put("params", params);
        JSONObject responseJsonObj = null;
        try {
            httpclient.getCredentialsProvider().setCredentials(new AuthScope("198.154.*.*", 34907),
                    new UsernamePasswordCredentials("username", "passssssssss_new"));
            StringEntity myEntity = new StringEntity(json.toJSONString());
            HttpPost httppost = new HttpPost("http://198.154.*.*:34907");

            System.out.println("executing request" + httppost.getRequestLine());
            HttpResponse response = httpclient.execute(httppost);
            HttpEntity entity = response.getEntity();

            if (entity != null) {
                System.out.println("Response content length: " + entity.getContentLength());
                // System.out.println(EntityUtils.toString(entity));
            JSONParser parser = new JSONParser();
            responseJsonObj = (JSONObject) parser.parse(EntityUtils.toString(entity));
        } catch (ClientProtocolException e) {
            // TODO Auto-generated catch block
        } catch (IOException e) {
            // TODO Auto-generated catch block
        } catch (ParseException e) {
            // TODO Auto-generated catch block
        } catch (org.json.simple.parser.ParseException e) {
            // TODO Auto-generated catch block
        } finally {
            // When HttpClient instance is no longer needed,
            // shut down the connection manager to ensure
            // immediate deallocation of all system resources
        return responseJsonObj;

    public Double getBalance(String account) {
        String[] params = { account };
        JSONObject json = invokeRPC(UUID.randomUUID().toString(), COMMAND_GET_BALANCE, Arrays.asList(params));
        return (Double)json.get("result");

    public String getNewAddress(String account) {
        String[] params = { account };
        JSONObject json = invokeRPC(UUID.randomUUID().toString(), COMMAND_GET_NEW_ADDRESS, Arrays.asList(params));
        return (String)json.get("result");

    public JSONObject getInfo() {
        JSONObject json = invokeRPC(UUID.randomUUID().toString(), COMMAND_GET_INFO, null);
        return (JSONObject)json.get("result");

    public JSONObject getInfo(String command) {
        JSONObject json = invokeRPC(UUID.randomUUID().toString(), command, null);
        return (JSONObject)json.get("result");

    /*public static void main(String[] args) {
        System.out.println(new RPCClient().getInfo());      

Current result:

executing requestPOST http://198.154.*.*:34907 HTTP/1.1
HTTP/1.1 403 Forbidden
Response content length: 0
Unexpected token END OF FILE at position 0.
    at org.json.simple.parser.JSONParser.parse(JSONParser.java:257)
    at org.json.simple.parser.JSONParser.parse(JSONParser.java:81)
    at org.json.simple.parser.JSONParser.parse(JSONParser.java:75)
    at RPCClient.invokeRPC(RPCClient.java:61)
    at RPCClient.getInfo(RPCClient.java:96)
    at KeccakTest.main(KeccakTest.java:125)
Exception in thread "main" java.lang.RuntimeException: java.lang.NullPointerException
    at KeccakTest.main(KeccakTest.java:129)
Caused by: java.lang.NullPointerException
    at RPCClient.getInfo(RPCClient.java:97)
    at KeccakTest.main(KeccakTest.java:125)
  • 1
    I see a POST call on 198.154.*.*:34907, what is this? If you try to access bitcoind from another host you should set rpcallowip=THE_OTHER_HOSTS_IP (or an IP-mask to allow access to the whole subnet, or rpcallowip=* to allow all IPs). Also, the standard port for the main network is 8332 and 18332 for testnet. Apr 30 '14 at 0:57
  • @George Kimionis, "198.154.xxx.xxx" is ip of the server, 34907 - port for JSON-RPC connections. Apr 30 '14 at 8:45
  • OK so did you try setting rpcallowip=*? Please add the configuration you are using inside the RPCClient.java file to your question. Apr 30 '14 at 12:16
  • 1
    @George Kimionis, thanks! "rpcallowip=*" was helpful. May 1 '14 at 11:24

In this line:

        HttpPost httppost = new HttpPost("http://198.154.*.*:34907");

the address 198.154.*.* is not valid IP address syntax. If that is really how your source code looks, then you need to use a full, valid IP address which is all numbers (for example, or whatever is appropriate for your network).

Even if you're deliberately obscuring your IP address for us, you still have a problem because you have set rpcallowip= which only allows that address to talk to the RPC server. Add another rpcallowip line that contains the address of the machine where you are running this Java code.

  • HttpPost httppost = new HttpPost("198.154.*.*:34907"); - I have hidden full ip address. There are numbers instead "*". May 1 '14 at 11:22

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