Estou lutando para buscar um token de solicitação do google ao tentar acessar as APIs. Estou recebendo a resposta padrão de 400. A solicitação que estou enviando é quase idêntica à gerada no playground OAuth que eles fornece

Estou usando o segredo / chave anônima e construímos uma string base da seguinte maneira:

GET&https%3A%2F%2Fwww.google.com%2Faccounts%2FOAuthGetRequestToken&oauth_callback%3Dhttp%253A%252F%252Fgooglecodesamples.com%252Foauth_playground%252Findex.php%26oauth_consumer_key%3Danonymous%26oauth_nonce%3D61dddc084c4e8adfa13d1509161939b0%26oauth_signature_method%3DHMAC-SHA1%26oauth_timestamp%3D1302853379%26oauth_version%3D1.0%26scope%3Dhttps%253A%252F%252Fwww.google.com%252Fcalendar%252Ffeeds%252F

Para depurar a solicitação que está sendo enviada, eu configuro o monitoramento TCP / IP no eclipse. No entanto, isso apenas monitora o tráfego HTTP, de modo que o seguinte é um reflexo de 99% do que está sendo solicitad

GET /accounts/OAuthGetRequestToken?scope=http%3A%2F%2Fwww.google.com%2Fcalendar%2Ffeeds%2F HTTP/1.1
Authorization: OAuth oauth_callback="http%3A%2F%2Fgooglecodesamples.com%2Foauth_playground%2Findex.php", oauth_consumer_key="anonymous", oauth_nonce="8cc04c7633db041dd0fd8e5fd0eb728e", oauth_signature="epRa5IZOA6s%2B3qhZa%2FUxuwYKnJA%3D", oauth_signature_method="HMAC-SHA1", oauth_timestamp="1302790583", oauth_version="1.0"
Accept: */*
User-Agent: Java/1.6.0_24
Host: localhost
Connection: keep-alive

Pode me dizer o que estou fazendo de errado? Desde já, obrigado

Abaixo é o único código que estou usando para iss

package com.pdw.gb;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;
import java.util.Calendar;
import java.util.Date;
import java.util.Random;

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

import com.google.gdata.util.common.util.Base64;

public class OAuthTest3 {

public static String read(String url) 
{
    StringBuffer buffer = new StringBuffer();
    try 
    {

        String[][] data = { 
                { "oauth_callback", URLEncoder.encode("http://googlecodesamples.com/oauth_playground/index.php","UTF-8") },
                { "oauth_consumer_key", "anonymous" },
                { "oauth_nonce", a64BitRandomString() },
                { "oauth_signature_method", "HMAC-SHA1" },
                { "oauth_timestamp", timeSinceEpochInMillis() },
                { "oauth_signature", "" },
                { "oauth_version", "1.0" },
                { "scope", URLEncoder.encode("https://www.google.com/calendar/feeds/","UTF-8") }
        };


        /**
         * Generation of the signature base string
         */
        String signature_base_string = "GET&"
                + URLEncoder.encode(url, "UTF-8") + "&";
        for (int i = 0; i < data.length; i++) 
        {
            // ignore the empty oauth_signature field
            if (i != 5) 
            {
                System.out.print(i);
                signature_base_string += URLEncoder.encode(data[i][0],
                        "UTF-8")
                        + "%3D"
                        + URLEncoder.encode(data[i][1], "UTF-8") + "%26";
            }
        }
        // cut the last appended %26
        signature_base_string = signature_base_string.substring(0,
                signature_base_string.length() - 3);

        /**
         * Sign the request
         */
        Mac m = Mac.getInstance("HmacSHA1");
        m.init(new SecretKeySpec("anonymous".getBytes(), "HmacSHA1"));
        m.update(signature_base_string.getBytes());
        byte[] res = m.doFinal();


        String sig = URLEncoder.encode(String.valueOf(Base64.encode(res)),"UTF8");
        data[5][1] = sig;

        /**
         * Create the header for the request
         */
        String header = "OAuth ";
        int i=0;
        for (String[] item : data) 
        {
            if (i!=7)
            {
                header += item[0] + "=\"" + item[1] + "\", ";
            }
            i++;
        }

        // cut off last appended comma
        header = header.substring(0, header.length() - 2);

        System.out.println("Signature Base String: "
                + signature_base_string);
        System.out.println("Authorization Header: " + header);
        System.out.println("Signature: " + sig);

        String charset = "UTF-8";
        URLConnection connection = new URL(url+"?scope="+URLEncoder.encode("https://www.google.com/calendar/feeds/", "UTF-8")).openConnection();
        connection.setRequestProperty("Authorization", header);
        connection.setRequestProperty("Accept", "*/*");


        BufferedReader reader = new BufferedReader(new InputStreamReader(
                connection.getInputStream()));

        String read;
        while ((read = reader.readLine()) != null) 
        {
            buffer.append(read);
        }
    } catch (Exception e) {
        e.printStackTrace();
    }

    return buffer.toString();
}

public static void main(String[] args) 
{
    boolean debug=false;
    if (!debug)
    {
        System.out.println(OAuthTest3
            .read("https://www.google.com/accounts/OAuthGetRequestToken"));
    }
    else
    {
            System.out.println(OAuthTest3
                    .read("http://localhost/accounts/OAuthGetRequestToken"));
    }
}

private static String a64BitRandomString() {
    StringBuffer sb = new StringBuffer();
    Random generator = new Random();

    for (int i = 0; i < 32; i++) {
        Integer r = generator.nextInt();
        if (r < 0) {
            r = r * -1;
        }
        r = r % 16;

        sb.append(r.toHexString(r));
    }

    return sb.toString();
}

private static String timeSinceEpochInMillis() {
    Calendar c = Calendar.getInstance();
    Date date = c.getTime();
    Long time = date.getTime();
    Integer i = (int) (time/1000);
    return i.toString();
}
}