content: package com.rsen.github.androidutilcode;
  
  import java.io.UnsupportedEncodingException;
  
  /**
   * <pre>
   *     author: Blankj
   *     blog  : http://blankj.com
   *     time  : 2016/8/16
   *     desc  : 字符串相关工具类
   * </pre>
   */
  public class StringUtils {
  
      private StringUtils() {
          throw new UnsupportedOperationException("u can't instantiate me...");
      }
  
      /**
       * 判断字符串是否为null或长度为0
       *
       * @param s 待校验字符串
       * @return {@code true}: 空<br> {@code false}: 不为空
       */
      public static boolean isEmpty(CharSequence s) {
          return s == null || s.length() == 0;
      }
  
      /**
       * 判断字符串是否为null或全为空格
       *
       * @param s 待校验字符串
       * @return {@code true}: null或全空格<br> {@code false}: 不为null且不全空格
       */
      public static boolean isSpace(String s) {
          return (s == null || s.trim().length() == 0);
      }
  
      /**
       * 判断两字符串是否相等
       *
       * @param a 待校验字符串a
       * @param b 待校验字符串b
       * @return @return {@code true}: 相等<br>{@code false}: 不相等
       */
      public static boolean equals(CharSequence a, CharSequence b) {
          if (a == b) return true;
          int length;
          if (a != null && b != null && (length = a.length()) == b.length()) {
              if (a instanceof String && b instanceof String) {
                  return a.equals(b);
              } else {
                  for (int i = 0; i < length; i++) {
                      if (a.charAt(i) != b.charAt(i)) return false;
                  }
                  return true;
              }
          }
          return false;
      }
  
      /**
       * null转为长度为0的字符串
       *
       * @param s 待转字符串
       * @return s为null转为长度为0字符串，否则不改变
       */
      public static String null2Length0(String s) {
          return s == null ? "" : s;
      }
  
      /**
       * 返回字符串长度
       *
       * @param s 字符串
       * @return null返回0，其他返回自身长度
       */
      public static int length(CharSequence s) {
          return s == null ? 0 : s.length();
      }
  
      /**
       * 首字母大写
       *
       * @param s 待转字符串
       * @return 首字母大写字符串
       */
      public static String upperFirstLetter(String s) {
          if (isEmpty(s) || !Character.isLowerCase(s.charAt(0))) {
              return s;
          }
          return String.valueOf((char) (s.charAt(0) - 32)) + s.substring(1);
      }
  
      /**
       * 首字母小写
       *
       * @param s 待转字符串
       * @return 首字母小写字符串
       */
      public static String lowerFirstLetter(String s) {
          if (isEmpty(s) || !Character.isUpperCase(s.charAt(0))) {
              return s;
          }
          return String.valueOf((char) (s.charAt(0) + 32)) + s.substring(1);
      }
  
      /**
       * 反转字符串
       *
       * @param s 待反转字符串
       * @return 反转字符串
       */
      public static String reverse(String s) {
          int len = length(s);
          if (len <= 1) return s;
          int mid = len >> 1;
          char[] chars = s.toCharArray();
          char c;
          for (int i = 0; i < mid; ++i) {
              c = chars[i];
              chars[i] = chars[len - i - 1];
              chars[len - i - 1] = c;
          }
          return new String(chars);
      }
  
      /**
       * 转化为半角字符
       *
       * @param s 待转字符串
       * @return 半角字符串
       */
      public static String toDBC(String s) {
          if (isEmpty(s)) {
              return s;
          }
          char[] chars = s.toCharArray();
          for (int i = 0, len = chars.length; i < len; i++) {
              if (chars[i] == 12288) {
                  chars[i] = ' ';
              } else if (65281 <= chars[i] && chars[i] <= 65374) {
                  chars[i] = (char) (chars[i] - 65248);
              } else {
                  chars[i] = chars[i];
              }
          }
          return new String(chars);
      }
  
      /**
       * 转化为全角字符
       *
       * @param s 待转字符串
       * @return 全角字符串
       */
      public static String toSBC(String s) {
          if (isEmpty(s)) {
              return s;
          }
          char[] chars = s.toCharArray();
          for (int i = 0, len = chars.length; i < len; i++) {
              if (chars[i] == ' ') {
                  chars[i] = (char) 12288;
              } else if (33 <= chars[i] && chars[i] <= 126) {
                  chars[i] = (char) (chars[i] + 65248);
              } else {
                  chars[i] = chars[i];
              }
          }
          return new String(chars);
      }
  
      private static int[] pyValue = new int[]{-20319, -20317, -20304, -20295, -20292, -20283, -20265, -20257, -20242,
              -20230, -20051, -20036, -20032,
              -20026, -20002, -19990, -19986, -19982, -19976, -19805, -19784, -19775, -19774, -19763, -19756, -19751,
              -19746, -19741, -19739, -19728,
              -19725, -19715, -19540, -19531, -19525, -19515, -19500, -19484, -19479, -19467, -19289, -19288, -19281,
              -19275, -19270, -19263, -19261,
              -19249, -19243, -19242, -19238, -19235, -19227, -19224, -19218, -19212, -19038, -19023, -19018, -19006,
              -19003, -18996, -18977, -18961,
              -18952, -18783, -18774, -18773, -18763, -18756, -18741, -18735, -18731, -18722, -18710, -18697, -18696,
              -18526, -18518, -18501, -18490,
              -18478, -18463, -18448, -18447, -18446, -18239, -18237, -18231, -18220, -18211, -18201, -18184, -18183,
              -18181, -18012, -17997, -17988,
              -17970, -17964, -17961, -17950, -17947, -17931, -17928, -17922, -17759, -17752, -17733, -17730, -17721,
              -17703, -17701, -17697, -17692,
              -17683, -17676, -17496, -17487, -17482, -17468, -17454, -17433, -17427, -17417, -17202, -17185, -16983,
              -16970, -16942, -16915, -16733,
              -16708, -16706, -16689, -16664, -16657, -16647, -16474, -16470, -16465, -16459, -16452, -16448, -16433,
              -16429, -16427, -16423, -16419,
              -16412, -16407, -16403, -16401, -16393, -16220, -16216, -16212, -16205, -16202, -16187, -16180, -16171,
              -16169, -16158, -16155, -15959,
              -15958, -15944, -15933, -15920, -15915, -15903, -15889, -15878, -15707, -15701, -15681, -15667, -15661,
              -15659, -15652, -15640, -15631,
              -15625, -15454, -15448, -15436, -15435, -15419, -15416, -15408, -15394, -15385, -15377, -15375, -15369,
              -15363, -15362, -15183, -15180,
              -15165, -15158, -15153, -15150, -15149, -15144, -15143, -15141, -15140, -15139, -15128, -15121, -15119,
              -15117, -15110, -15109, -14941,
              -14937, -14933, -14930, -14929, -14928, -14926, -14922, -14921, -14914, -14908, -14902, -14894, -14889,
              -14882, -14873, -14871, -14857,
              -14678, -14674, -14670, -14668, -14663, -14654, -14645, -14630, -14594, -14429, -14407, -14399, -14384,
              -14379, -14368, -14355, -14353,
              -14345, -14170, -14159, -14151, -14149, -14145, -14140, -14137, -14135, -14125, -14123, -14122, -14112,
              -14109, -14099, -14097, -14094,
              -14092, -14090, -14087, -14083, -13917, -13914, -13910, -13907, -13906, -13905, -13896, -13894, -13878,
              -13870, -13859, -13847, -13831,
              -13658, -13611, -13601, -13406, -13404, -13400, -13398, -13395, -13391, -13387, -13383, -13367, -13359,
              -13356, -13343, -13340, -13329,
              -13326, -13318, -13147, -13138, -13120, -13107, -13096, -13095, -13091, -13076, -13068, -13063, -13060,
              -12888, -12875, -12871, -12860,
              -12858, -12852, -12849, -12838, -12831, -12829, -12812, -12802, -12607, -12597, -12594, -12585, -12556,
              -12359, -12346, -12320, -12300,
              -12120, -12099, -12089, -12074, -12067, -12058, -12039, -11867, -11861, -11847, -11831, -11798, -11781,
              -11604, -11589, -11536, -11358,
              -11340, -11339, -11324, -11303, -11097, -11077, -11067, -11055, -11052, -11045, -11041, -11038, -11024,
              -11020, -11019, -11018, -11014,
              -10838, -10832, -10815, -10800, -10790, -10780, -10764, -10587, -10544, -10533, -10519, -10331, -10329,
              -10328, -10322, -10315, -10309,
              -10307, -10296, -10281, -10274, -10270, -10262, -10260, -10256, -10254};
  
      private static String[] pyStr = new String[]{"a", "ai", "an", "ang", "ao", "ba", "bai", "ban", "bang", "bao",
              "bei", "ben", "beng", "bi", "bian",
              "biao", "bie", "bin", "bing", "bo", "bu", "ca", "cai", "can", "cang", "cao", "ce", "ceng", "cha", "chai",
              "chan", "chang", "chao", "che",
              "chen", "cheng", "chi", "chong", "chou", "chu", "chuai", "chuan", "chuang", "chui", "chun", "chuo", "ci",
              "cong", "cou", "cu", "cuan",
              "cui", "cun", "cuo", "da", "dai", "dan", "dang", "dao", "de", "deng", "di", "dian", "diao", "die",
              "ding", "diu", "dong", "dou", "du",
              "duan", "dui", "dun", "duo", "e", "en", "er", "fa", "fan", "fang", "fei", "fen", "feng", "fo", "fou",
              "fu", "ga", "gai", "gan", "gang",
              "gao", "ge", "gei", "gen", "geng", "gong", "gou", "gu", "gua", "guai", "guan", "guang", "gui", "gun",
              "guo", "ha", "hai", "han", "hang",
              "hao", "he", "hei", "hen", "heng", "hong", "hou", "hu", "hua", "huai", "huan", "huang", "hui", "hun",
              "huo", "ji", "jia", "jian",
              "jiang", "jiao", "jie", "jin", "jing", "jiong", "jiu", "ju", "juan", "jue", "jun", "ka", "kai", "kan",
              "kang", "kao", "ke", "ken",
              "keng", "kong", "kou", "ku", "kua", "kuai", "kuan", "kuang", "kui", "kun", "kuo", "la", "lai", "lan",
              "lang", "lao", "le", "lei", "leng",
              "li", "lia", "lian", "liang", "liao", "lie", "lin", "ling", "liu", "long", "lou", "lu", "lv", "luan",
              "lue", "lun", "luo", "ma", "mai",
              "man", "mang", "mao", "me", "mei", "men", "meng", "mi", "mian", "miao", "mie", "min", "ming", "miu",
              "mo", "mou", "mu", "na", "nai",
              "nan", "nang", "nao", "ne", "nei", "nen", "neng", "ni", "nian", "niang", "niao", "nie", "nin", "ning",
              "niu", "nong", "nu", "nv", "nuan",
              "nue", "nuo", "o", "ou", "pa", "pai", "pan", "pang", "pao", "pei", "pen", "peng", "pi", "pian", "piao",
              "pie", "pin", "ping", "po", "pu",
              "qi", "qia", "qian", "qiang", "qiao", "qie", "qin", "qing", "qiong", "qiu", "qu", "quan", "que", "qun",
              "ran", "rang", "rao", "re",
              "ren", "reng", "ri", "rong", "rou", "ru", "ruan", "rui", "run", "ruo", "sa", "sai", "san", "sang", "sao",
              "se", "sen", "seng", "sha",
              "shai", "shan", "shang", "shao", "she", "shen", "sheng", "shi", "shou", "shu", "shua", "shuai", "shuan",
              "shuang", "shui", "shun",
              "shuo", "si", "song", "sou", "su", "suan", "sui", "sun", "suo", "ta", "tai", "tan", "tang", "tao", "te",
              "teng", "ti", "tian", "tiao",
              "tie", "ting", "tong", "tou", "tu", "tuan", "tui", "tun", "tuo", "wa", "wai", "wan", "wang", "wei",
              "wen", "weng", "wo", "wu", "xi",
              "xia", "xian", "xiang", "xiao", "xie", "xin", "xing", "xiong", "xiu", "xu", "xuan", "xue", "xun", "ya",
              "yan", "yang", "yao", "ye", "yi",
              "yin", "ying", "yo", "yong", "you", "yu", "yuan", "yue", "yun", "za", "zai", "zan", "zang", "zao", "ze",
              "zei", "zen", "zeng", "zha",
              "zhai", "zhan", "zhang", "zhao", "zhe", "zhen", "zheng", "zhi", "zhong", "zhou", "zhu", "zhua", "zhuai",
              "zhuan", "zhuang", "zhui",
              "zhun", "zhuo", "zi", "zong", "zou", "zu", "zuan", "zui", "zun", "zuo"};
  
      /**
       * 单个汉字转成ASCII码
       *
       * @param s 单个汉字字符串
       * @return 如果字符串长度是1返回的是对应的ascii码，否则返回-1
       */
      private static int oneCn2ASCII(String s) {
          if (s.length() != 1) return -1;
          int ascii = 0;
          try {
              byte[] bytes = s.getBytes("GB2312");
              if (bytes.length == 1) {
                  ascii = bytes[0];
              } else if (bytes.length == 2) {
                  int highByte = 256 + bytes[0];
                  int lowByte = 256 + bytes[1];
                  ascii = (256 * highByte + lowByte) - 256 * 256;
              } else {
                  throw new IllegalArgumentException("Illegal resource string");
              }
          } catch (UnsupportedEncodingException e) {
              e.printStackTrace();
          }
          return ascii;
      }
  
      /**
       * 单个汉字转成拼音
       *
       * @param s 单个汉字字符串
       * @return 如果字符串长度是1返回的是对应的拼音，否则返回{@code null}
       */
      private static String oneCn2PY(String s) {
          int ascii = oneCn2ASCII(s);
          if (ascii == -1) return null;
          String ret = null;
          if (0 <= ascii && ascii <= 127) {
              ret = String.valueOf((char) ascii);
          } else {
              for (int i = pyValue.length - 1; i >= 0; i--) {
                  if (pyValue[i] <= ascii) {
                      ret = pyStr[i];
                      break;
                  }
              }
          }
          return ret;
      }
  
      /**
       * 获得第一个汉字首字母
       *
       * @param s 单个汉字字符串
       * @return 拼音
       */
      public static String getPYFirstLetter(String s) {
          if (isSpace(s)) return "";
          String first, py;
          first = s.substring(0, 1);
          py = oneCn2PY(first);
          if (py == null) return null;
          return py.substring(0, 1);
      }
  
      /**
       * 中文转拼音
       *
       * @param s 汉字字符串
       * @return 拼音
       */
      public static String cn2PY(String s) {
          String hz, py;
          StringBuilder sb = new StringBuilder();
          for (int i = 0; i < s.length(); i++) {
              hz = s.substring(i, i + 1);
              py = oneCn2PY(hz);
              if (py == null) {
                  py = "?";
              }
              sb.append(py);
          }
          return sb.toString();
      }
  }
  