Java tutorial
/* * Copyright 2007 Yusuke Yamamoto * * 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. */ package twitter4j.internal.json; import twitter4j.TwitterException; import twitter4j.TwitterResponse; import twitter4j.internal.http.HttpResponse; import twitter4j.internal.org.json.JSONException; import twitter4j.internal.org.json.JSONObject; import java.io.UnsupportedEncodingException; import java.net.URLDecoder; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.*; import java.util.concurrent.LinkedBlockingQueue; /** * A tiny parse utility class. * * @author Yusuke Yamamoto - yusuke at mac.com */ public final class z_T4JInternalParseUtil { private z_T4JInternalParseUtil() { // should never be instantiated throw new AssertionError(); } static String getUnescapedString(String str, JSONObject json) { return HTMLEntity.unescape(getRawString(str, json)); } public static String getRawString(String name, JSONObject json) { try { if (json.isNull(name)) { return null; } else { return json.getString(name); } } catch (JSONException jsone) { return null; } } static String getURLDecodedString(String name, JSONObject json) { String returnValue = getRawString(name, json); if (returnValue != null) { try { returnValue = URLDecoder.decode(returnValue, "UTF-8"); } catch (UnsupportedEncodingException ignore) { } } return returnValue; } public static Date parseTrendsDate(String asOfStr) throws TwitterException { Date parsed; switch (asOfStr.length()) { case 10: parsed = new Date(Long.parseLong(asOfStr) * 1000); break; case 20: parsed = getDate(asOfStr, "yyyy-MM-dd'T'HH:mm:ss'Z'"); break; default: parsed = getDate(asOfStr, "EEE, d MMM yyyy HH:mm:ss z"); } return parsed; } public static Date getDate(String name, JSONObject json) throws TwitterException { return getDate(name, json, "EEE MMM d HH:mm:ss z yyyy"); } public static Date getDate(String name, JSONObject json, String format) throws TwitterException { String dateStr = getUnescapedString(name, json); if ("null".equals(dateStr) || null == dateStr) { return null; } else { return getDate(dateStr, format); } } private final static Map<String, LinkedBlockingQueue<SimpleDateFormat>> formatMapQueue = new HashMap<String, LinkedBlockingQueue<SimpleDateFormat>>(); public static Date getDate(String dateString, String format) throws TwitterException { LinkedBlockingQueue<SimpleDateFormat> simpleDateFormats = formatMapQueue.get(format); if (simpleDateFormats == null) { simpleDateFormats = new LinkedBlockingQueue<SimpleDateFormat>(); formatMapQueue.put(format, simpleDateFormats); } SimpleDateFormat sdf = simpleDateFormats.poll(); if (null == sdf) { sdf = new SimpleDateFormat(format, Locale.US); sdf.setTimeZone(TimeZone.getTimeZone("UTC")); } try { return sdf.parse(dateString); } catch (ParseException pe) { throw new TwitterException("Unexpected date format(" + dateString + ") returned from twitter.com", pe); } finally { try { simpleDateFormats.put(sdf); } catch (InterruptedException ignore) { // the size of LinkedBlockingQueue is Integer.MAX by default. // there is no need to concern about this situation } } } public static int getInt(String name, JSONObject json) { return getInt(getRawString(name, json)); } public static int getInt(String str) { if (null == str || "".equals(str) || "null".equals(str)) { return -1; } else { try { return Integer.valueOf(str); } catch (NumberFormatException nfe) { // workaround for the API side issue http://twitter4j.org/jira/browse/TFJ-484 return -1; } } } public static long getLong(String name, JSONObject json) { return getLong(getRawString(name, json)); } public static long getLong(String str) { if (null == str || "".equals(str) || "null".equals(str)) { return -1; } else { // some count over 100 will be expressed as "100+" if (str.endsWith("+")) { str = str.substring(0, str.length() - 1); return Long.valueOf(str) + 1; } return Long.valueOf(str); } } public static double getDouble(String name, JSONObject json) { String str2 = getRawString(name, json); if (null == str2 || "".equals(str2) || "null".equals(str2)) { return -1; } else { return Double.valueOf(str2); } } public static boolean getBoolean(String name, JSONObject json) { String str = getRawString(name, json); if (null == str || "null".equals(str)) { return false; } return Boolean.valueOf(str); } public static int toAccessLevel(HttpResponse res) { if (null == res) { return -1; } String xAccessLevel = res.getResponseHeader("X-Access-Level"); int accessLevel; if (null == xAccessLevel) { accessLevel = TwitterResponse.NONE; } else { // https://dev.twitter.com/pages/application-permission-model-faq#how-do-we-know-what-the-access-level-of-a-user-token-is switch (xAccessLevel.length()) { // read? (Read-only) case 4: accessLevel = TwitterResponse.READ; break; case 10: // read-write? (Read & Write) accessLevel = TwitterResponse.READ_WRITE; break; case 25: // read-write-directmessages? (Read, Write, & Direct Message) accessLevel = TwitterResponse.READ_WRITE_DIRECTMESSAGES; break; case 26: // read-write-privatemessages? (Read, Write, & Direct Message) accessLevel = TwitterResponse.READ_WRITE_DIRECTMESSAGES; break; default: accessLevel = TwitterResponse.NONE; // unknown access level; } } return accessLevel; } }