android开发字符串工具类(一)

 package com.gzcivil.utils;

 import java.io.BufferedReader;
 import java.io.ByteArrayOutputStream;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.math.BigDecimal;
 import java.text.SimpleDateFormat;
 import java.util.Arrays;
 import java.util.Calendar;
 import java.util.Date;
 import java.util.Locale;
 import java.util.StringTokenizer;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 /**
  * 字符串工具
  *
  * @author LiJinlun
  * @time 2015-12-5
  */
 public class StringUtils {

     private static StringUtils instance;

     private StringUtils() {
         super();
     }

     public static String getDateTimeToString(Calendar cal, String format) {
         return getDateTimeToString(cal.getTimeInMillis(), format);
     }

     public static String getDateTimeToString(long longTime, String format) {
         SimpleDateFormat sdf = new SimpleDateFormat(format, Locale.getDefault());
         Date date = new Date(longTime);
         return sdf.format(date);
     }

     public static synchronized StringUtils getInstance() {
         if (instance == null)
             instance = new StringUtils();
         return instance;
     }

     /** 将一个字符串从第一位开始截取到有数字出现的地方 */
     public static String clearNumberString(String str) {
         int minIndex = Integer.MAX_VALUE;
         int[] index = new int[10];
         for (int i = 0; i < 10; i++) {
             index[i] = str.indexOf(String.valueOf(i));
             if (index[i] != -1 && index[i] < minIndex) {
                 minIndex = index[i];
             }
         }
         if (minIndex < Integer.MAX_VALUE) {
             str = str.substring(0, minIndex);
         }
         return str;
     }

     /**
      * 判断字符串是否为空
      */
     public static boolean isEmpty(String str) {
         return null == str || str.trim().equals("");
     }

     /**
      * 描述：手机号格式验证.
      *
      * @param str
      *            指定的手机号码字符串
      * @return 是否为手机号码格式:是为true，否则false
      */
     public static Boolean isMobilePhone(String str) {
         Boolean isMobileNo = false;
         try {
             Pattern p = Pattern.compile("^((13[0-9])|(14[0-9])|(15[0-9])|(16[0-9])|(17[0-9])|(18[0-9])|(19[0-9]))\\d{8}$");
             Matcher m = p.matcher(str);
             isMobileNo = m.matches();
         } catch (Exception e) {
             e.printStackTrace();
         }
         return isMobileNo;
     }

     /**
      * 获取字串字节长度
      *
      * @param str
      * @return
      */
     public static int getLength(String str) {
         return str.replaceAll("[^\\x00-\\xff]", "**").trim().length();
     }

     /** 返回double数据d小数点后面2位有效数字 */
     public static double getDouble(double d) {
         return new BigDecimal(d).setScale(2, BigDecimal.ROUND_HALF_UP).doubleValue();
     }

     /** 从double型返回String型，精确到小数点后2位 */
     public static String getStringByDouble(double d) {
         String str = String.valueOf(new BigDecimal(d).setScale(2, BigDecimal.ROUND_HALF_UP).doubleValue());
         try {
             int index = str.indexOf('.');
             if (index != -1) {
                 String tmpStr = str.substring(index + 1);
                 if ("0".equals(tmpStr)) {
                     str = str.substring(0, index);
                 }
             }
         } catch (Exception e) {
             e.printStackTrace();
         }
         return str;
     }

     public static String getCorrectDistance(int distance) {
         String result = "";
         if (distance < 20) {
             result = "附近";
         } else if (distance < 1000) {
             result = distance + "m";
         } else {
             result = String.format("%.1f", distance / 1000f) + "km";
         }
         return result;
     }

     /**
      * 将秒数转换成文字描述
      *
      * @param tm单位秒
      */
     public static String secondsToString(int tm) {
         if (tm <= 0)
             return "00:00:00";
         long hour = tm / 3600;
         tm = tm % 3600;
         long min = tm / 60;
         tm = tm % 60;

         String result = "";
         if (hour < 10) {
             result = "0" + hour + ":";
         } else {
             result = String.valueOf(hour) + ":";
         }

         if (min < 10) {
             result += "0" + min + ":";
         } else {
             result += min + ":";
         }

         if (tm < 10) {
             result += "0" + tm;
         } else {
             result += String.valueOf(tm);
         }
         return result;
     }

     /**
      * 检测是否JSON字串
      *
      * @param source
      * @return
      */
     public static boolean isJson(String source) {
         String tmp = null == source ? "" : source.trim();
         if ("".equals(tmp) || tmp.length() < 1)
             return false;
         else if (tmp.startsWith("{") && tmp.endsWith("}"))
             return true;
         else if (tmp.startsWith("[") && tmp.endsWith("]"))
             return true;
         else
             return false;
     }

     public static String str2int(String source) {
         String result = "";
         LogUtils.i("ls", "result" + result);
         for (int i = 0; i < source.length(); i++) {
             if (source.charAt(i) >= '0' && source.charAt(i) <= '9')
                 result += source.charAt(i);

         }
         return result;
     }

     /**
      * MD5编码
      *
      * @param source
      * @return
      */
     public static String md5(byte[] source) {
         char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
         try {
             java.security.MessageDigest md = java.security.MessageDigest.getInstance("MD5");
             md.update(source);
             byte tmp[] = md.digest();
             char str[] = new char[16 * 2];
             for (int i = 0, k = 0; i < 16; i++) {
                 byte byte0 = tmp[i];
                 str[k++] = hexDigits[byte0 >>> 4 & 0xf];
                 str[k++] = hexDigits[byte0 & 0xf];
             }
             return new String(str);
         } catch (Exception e) {
             LogUtils.e("md5(): error=" + e.getMessage(), "StringTool");
             return "";
         }
     }

     /**
      * base64编码,将字节数组编码为字符串
      *
      * @param source
      * @return String
      */
     public static String base64_encode(byte[] source) {
         char[] base64EncodeChars = new char[] { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/' };
         try {
             StringBuffer sb = new StringBuffer();
             int len = source.length;
             int i = 0;
             int b1, b2, b3;
             while (i < len) {
                 b1 = source[i++] & 0xff;
                 if (i == len) {
                     sb.append(base64EncodeChars[b1 >>> 2]);
                     sb.append(base64EncodeChars[(b1 & 0x3) << 4]);
                     sb.append("==");
                     break;
                 }
                 b2 = source[i++] & 0xff;
                 if (i == len) {
                     sb.append(base64EncodeChars[b1 >>> 2]);
                     sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]);
                     sb.append(base64EncodeChars[(b2 & 0x0f) << 2]);
                     sb.append("=");
                     break;
                 }
                 b3 = source[i++] & 0xff;
                 sb.append(base64EncodeChars[b1 >>> 2]);
                 sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]);
                 sb.append(base64EncodeChars[((b2 & 0x0f) << 2) | ((b3 & 0xc0) >>> 6)]);
                 sb.append(base64EncodeChars[b3 & 0x3f]);
             }
             return sb.toString();
         } catch (Exception e) {
             LogUtils.e("base64_encode(): error=" + e.getMessage(), "StringTool");
             return "";
         }
     }

     /**
      * base64编码,解码为字节数组
      *
      * @param source
      * @return byte[]
      */
     public static byte[] base64_decode(String source) {
         byte[] base64DecodeChars = new byte[] { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1 };
         try {
             byte[] data = source.getBytes();
             int len = data.length;
             ByteArrayOutputStream buf = new ByteArrayOutputStream(len);
             int i = 0;
             int b1, b2, b3, b4;
             while (i < len) {
                 /* b1 */
                 do {
                     b1 = base64DecodeChars[data[i++]];
                 } while (i < len && b1 == -1);
                 if (b1 == -1)
                     break;

                 /* b2 */
                 do {
                     b2 = base64DecodeChars[data[i++]];
                 } while (i < len && b2 == -1);
                 if (b2 == -1)
                     break;
                 buf.write((int) ((b1 << 2) | ((b2 & 0x30) >>> 4)));

                 /* b3 */
                 do {
                     b3 = data[i++];
                     if (b3 == 61)
                         return buf.toByteArray();
                     b3 = base64DecodeChars[b3];
                 } while (i < len && b3 == -1);
                 if (b3 == -1)
                     break;
                 buf.write((int) (((b2 & 0x0f) << 4) | ((b3 & 0x3c) >>> 2)));

                 /* b4 */
                 do {
                     b4 = data[i++];
                     if (b4 == 61)
                         return buf.toByteArray();
                     b4 = base64DecodeChars[b4];
                 } while (i < len && b4 == -1);
                 if (b4 == -1)
                     break;
                 buf.write((int) (((b3 & 0x03) << 6) | b4));
             }
             return buf.toByteArray();
         } catch (Exception e) {
             LogUtils.i("ls", "base64_decode(): error=" + e.getMessage());
             return "".getBytes();
         }
     }

     public static String join(String separator, Object[] o) {
         return implode(separator, Arrays.asList(o));
     }

     protected static <T> String implode(String separator, Iterable<T> elements) {
         StringBuilder out = new StringBuilder();
         boolean first = true;
         for (Object s : elements) {
             if (s == null)
                 continue;
             else if (first)
                 first = false;
             else
                 out.append(separator);
             out.append(s);
         }
         return out.toString();
     }

     public static String[] explode(String glue, String str) {
         String[] outData;
         try {
             StringTokenizer st = new StringTokenizer(str, glue);
             outData = new String[st.countTokens()];
             for (int i = 0; st.hasMoreTokens();) {
                 outData[i++] = st.nextToken();
             }
         } catch (Exception e) {
             outData = new String[] { str };
             e.printStackTrace();
         }
         return outData;
     }

     /**
      * 得到字符串双字节长度
      *
      * @param str
      * @return
      */
     public static int getDoubleByteLength(String str) {
         return str.replaceAll("[^\\x00-\\xff]", "xx").trim().length();
     }

     /**
      * 将流转换成字符串
      *
      * @param is
      * @return
      */
     public static String getStringByStream(InputStream is) {
         StringBuffer sb = new StringBuffer();
         try {
             BufferedReader br = new BufferedReader(new InputStreamReader(is));
             String line = null;
             while ((line = br.readLine()) != null) {
                 sb.append(line);
             }
         } catch (Exception e) {
             e.printStackTrace();
         }
         return sb.toString();
     }

     /**
      * 将流转换成字符串
      *
      * @param is
      * @param chatset
      *            字符编码
      * @return
      */
     public static String getStringByStream(InputStream is, String chatset) {
         StringBuffer sb = new StringBuffer();
         try {
             byte[] bytes = new byte[1024];
             int len = 0;
             while ((len = is.read(bytes)) != -1) {
                 sb.append(new String(bytes, 0, len, chatset));
             }
         } catch (Exception e) {
             // TODO: handle exception
             e.printStackTrace();
         }
         return sb.toString();
     }

 }