Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright 2010 Mark Wyszomierski
 * Portions Copyright (c) 2008-2010 Facebook, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import android.os.Bundle;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class Main {
    /**
     * Connect to an HTTP URL and return the response as a string.
     * 
     * Note that the HTTP method override is used on non-GET requests. (i.e.
     * requests are made as "POST" with method specified in the body).
     * 
     * @param url - the resource to open: must be a welformed URL
     * @param method - the HTTP method to use ("GET", "POST", etc.)
     * @param params - the query parameter for the URL (e.g. access_token=foo)
     * @return the URL contents as a String
     * @throws MalformedURLException - if the URL format is invalid
     * @throws IOException - if a network problem occurs
     */
    public static String openUrl(String url, String method, Bundle params)
            throws MalformedURLException, IOException {
        if (method.equals("GET")) {
            url = url + "?" + encodeUrl(params);
        }

        HttpURLConnection conn = (HttpURLConnection) new URL(url).openConnection();
        conn.setRequestProperty("User-Agent",
                System.getProperties().getProperty("http.agent") + " FacebookAndroidSDK");
        if (!method.equals("GET")) {
            // use method override
            params.putString("method", method);
            conn.setRequestMethod("POST");
            conn.setDoOutput(true);
            conn.getOutputStream().write(encodeUrl(params).getBytes("UTF-8"));
        }

        String response = "";
        try {
            response = read(conn.getInputStream());
        } catch (FileNotFoundException e) {
            // Error Stream contains JSON that we can parse to a FB error
            response = read(conn.getErrorStream());
        }

        return response;
    }

    public static String encodeUrl(Bundle parameters) {
        if (parameters == null) {
            return "";
        }

        StringBuilder sb = new StringBuilder();
        boolean first = true;
        for (String key : parameters.keySet()) {
            if (first)
                first = false;
            else
                sb.append("&");
            sb.append(key + "=" + parameters.getString(key));
        }
        return sb.toString();
    }

    private static String read(InputStream in) throws IOException {
        StringBuilder sb = new StringBuilder();
        BufferedReader r = new BufferedReader(new InputStreamReader(in), 1000);
        for (String line = r.readLine(); line != null; line = r.readLine()) {
            sb.append(line);
        }
        in.close();
        return sb.toString();
    }
}