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常用的java函数

    博客分类:
  • Java
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/** 
    * 将某个日期以固定格式转化成字符串 
    *  
    * @param date 
    * @return String 
    */ 
   public static String dateToStr(java.util.Date date)  
   {  
       SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");  
       String str = sdf.format(date);  
       return str;  
   } 

/** 
 * 判断任意一个整数是否素数 
 *  
 * @param n 
 * @return boolean 
 */ 
public static boolean isPrimes(int n)  
{  
    for (int i = 2; i <= Math.sqrt(n); i++)  
    {  
        if (n % i == 0)  
        {  
            return false;  
        }  
    }  
    return true;  

/** 
 * 获得任意一个整数的阶乘,递归 
  *  
 * @param n 
 * @return n! 
 */ 
public static int factorial(int n)  
{  
    if (n == 1)  
    {  
        return 1;  
    }  
    return n * factorial(n - 1);  

/** 
 * 将指定byte数组以16进制的形式打印到控制台 
  *  
 * @param hint String 
 * @param b byte[]             
 * @return void  
 */ 
public static void printHexString(String hint, byte[] b)  
{  
    System.out.print(hint);  
    for (int i = 0; i < b.length; i++)  
    {  
        String hex = Integer.toHexString(b[i] & 0xFF);  
        if (hex.length() == 1)  
        {  
            hex = '0' + hex;  
        }  
        System.out.print(hex.toUpperCase() + " ");  
    }  
    System.out.println("");  

常用的java函数(二) 常用字符串处理
 /** 
   * 分割字符串 
   *  
   * @param str String 原始字符串 
   * @param splitsign String 分隔符 
   * @return String[] 分割后的字符串数组 
   */ 
  public static String[] split(String str, String splitsign) {  
    int index;  
    if (str == null || splitsign == null)  
      return null;  
    ArrayList al = new ArrayList();  
    while ((index = str.indexOf(splitsign)) != -1) {  
      al.add(str.substring(0, index));  
      str = str.substring(index + splitsign.length());  
    }  
    al.add(str);  
    return (String[]) al.toArray(new String[0]);  
  }  
 
  /** 
   * 替换字符串 
   *  
   * @param from String 原始字符串 
   * @param to String 目标字符串 
   * @param source String 母字符串 
   * @return String 替换后的字符串 
   */ 
  public static String replace(String from, String to, String source) {  
    if (source == null || from == null || to == null)  
      return null;  
    StringBuffer bf = new StringBuffer("");  
    int index = -1;  
    while ((index = source.indexOf(from)) != -1) {  
      bf.append(source.substring(0, index) + to);  
      source = source.substring(index + from.length());  
      index = source.indexOf(from);  
    }  
    bf.append(source);  
    return bf.toString();  
  }  
 
  /** 
   * 替换字符串,能能够在HTML页面上直接显示(替换双引号和小于号) 
   *  
   * @param str String 原始字符串 
   * @return String 替换后的字符串 
   */ 
  public static String htmlencode(String str) {  
    if (str == null) {  
      return null;  
    }  
 
    return replace("\"", "&quot;", replace("<", "&lt;", str));  
  }  
 
  /** 
   * 替换字符串,将被编码的转换成原始码(替换成双引号和小于号) 
   *  
   * @param str String 
   * @return String 
   */ 
  public static String htmldecode(String str) {  
    if (str == null) {  
      return null;  
    }  
 
    return replace("&quot;", "\"", replace("&lt;", "<", str));  
  }  
 
  private static final String _BR = "<br/>";  
 
  /** 
   * 在页面上直接显示文本内容,替换小于号,空格,回车,TAB 
   *  
   * @param str String 原始字符串 
   * @return String 替换后的字符串 
   */ 
  public static String htmlshow(String str) {  
    if (str == null) {  
      return null;  
    }  
 
    str = replace("<", "&lt;", str);  
    str = replace(" ", "&nbsp;", str);  
    str = replace("\r\n", _BR, str);  
    str = replace("\n", _BR, str);  
    str = replace("\t", "&nbsp;&nbsp;&nbsp;&nbsp;", str);  
    return str;  
  }  
 
  /** 
   * 返回指定字节长度的字符串 
   *  
   * @param str String 字符串 
   * @param length int 指定长度 
   * @return String 返回的字符串 
   */ 
  public static String toLength(String str, int length) {  
    if (str == null) {  
      return null;  
    }  
    if (length <= 0) {  
      return "";  
    }  
    try {  
      if (str.getBytes("GBK").length <= length) {  
        return str;  
      }  
    } catch (Exception ex) {  
    }  
    StringBuffer buff = new StringBuffer();  
 
    int index = 0;  
    char c;  
    length -= 3;  
    while (length > 0) {  
      c = str.charAt(index);  
      if (c < 128) {  
        length--;  
      } else {  
        length--;  
        length--;  
      }  
      buff.append(c);  
      index++;  
    }  
    buff.append("");  
    return buff.toString();  
  }  
 
  /** 
   * 判断是否为整数 
   *  
   * @param str 传入的字符串 
   * @return 是整数返回true,否则返回false 
   */ 
  public static boolean isInteger(String str) {  
    Pattern pattern = Pattern.compile("^[-\\+]?[\\d]*$");  
    return pattern.matcher(str).matches();  
  }  
 
  /** 
   * 判断是否为浮点数,包括double和float 
   *  
   * @param str 传入的字符串 
   * @return 是浮点数返回true,否则返回false 
   */ 
  public static boolean isDouble(String str) {  
    Pattern pattern = Pattern.compile("^[-\\+]?[.\\d]*$");  
    return pattern.matcher(str).matches();  
  }  
 
  /** 
   * 判断输入的字符串是否符合Email样式. 
   *  
   * @param str 传入的字符串 
   * @return 是Email样式返回true,否则返回false 
   */ 
  public static boolean isEmail(String str) {  
    Pattern pattern = Pattern.compile("^\\w+([-+.]\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*$");  
    return pattern.matcher(str).matches();  
  }  
 
  /** 
   * 判断输入的字符串是否为纯汉字 
   *  
   * @param str 传入的字符窜 
   * @return 如果是纯汉字返回true,否则返回false 
   */ 
  public static boolean isChinese(String str) {  
    Pattern pattern = Pattern.compile("[\u0391-\uFFE5]+$");  
    return pattern.matcher(str).matches();  
  }  
 
  /** 
   * 是否为空白,包括null和"" 
   *  
   * @param str 
   * @return 
   */ 
  public static boolean isBlank(String str) {  
    return str == null || str.trim().length() == 0;  
  }  
 
  /** 
   * 判断是否为质数 
   *  
   * @param x 
   * @return 
   */ 
  public static boolean isPrime(int x) {  
    if (x <= 7) {  
      if (x == 2 || x == 3 || x == 5 || x == 7)  
        return true;  
    }  
    int c = 7;  
    if (x % 2 == 0)  
      return false;  
    if (x % 3 == 0)  
      return false;  
    if (x % 5 == 0)  
      return false;  
    int end = (int) Math.sqrt(x);  
    while (c <= end) {  
      if (x % c == 0) {  
        return false;  
      }  
      c += 4;  
      if (x % c == 0) {  
        return false;  
      }  
      c += 2;  
      if (x % c == 0) {  
        return false;  
      }  
      c += 4;  
      if (x % c == 0) {  
        return false;  
      }  
      c += 2;  
      if (x % c == 0) {  
        return false;  
      }  
      c += 4;  
      if (x % c == 0) {  
        return false;  
      }  
      c += 6;  
      if (x % c == 0) {  
        return false;  
      }  
      c += 2;  
      if (x % c == 0) {  
        return false;  
      }  
      c += 6;  
    }  
    return true;  
  }  
    /** 
     * 全角字符转半角字符 
     *  
     * @param QJStr 
     * @return String 
     */ 
    public static final String QJToBJChange(String QJStr)  
    {  
        char[] chr = QJStr.toCharArray();  
        String str = "";  
        for (int i = 0; i < chr.length; i++)  
        {  
            chr[i] = (char) ((int) chr[i] - 65248);  
            str += chr[i];  
        }  
        return str;  
    }  
    /** 
     * 去掉字符串中重复的子字符串 
     *  
     * @param str 
     * @return String 
     */ 
    private static String removeSameString(String str)  
    {  
        Set<String> mLinkedSet = new LinkedHashSet<String>();  
        String[] strArray = str.split(" ");  
        StringBuffer sb = new StringBuffer();  
 
        for (int i = 0; i < strArray.length; i++)  
        {  
            if (!mLinkedSet.contains(strArray[i]))  
            {  
                mLinkedSet.add(strArray[i]);  
                sb.append(strArray[i] + " ");  
            }  
        }  
        System.out.println(mLinkedSet);  
        return sb.toString().substring(0, sb.toString().length() - 1);  
      }  
//过滤特殊字符  
public static String encoding(String src){  
        if (src==null)  
            return "";  
        StringBuilder result=new StringBuilder();  
        if (src!=null){  
            src=src.trim();  
            for (int pos=0;pos<src.length();pos++){  
                switch(src.charAt(pos)){  
                    case '\"':result.append("&quot;");break;  
                    case '<':result.append("&lt;");break;  
                    case '>':result.append("&gt;");break;  
                    case '\'':result.append("&apos;");break;  
                    case '&':result.append("&amp;");break;  
                    case '%':result.append("&pc;");break;  
                    case '_':result.append("&ul;");break;  
                    case '#':result.append("&shap;");break;  
                    case '?':result.append("&ques;");break;  
                    default:result.append(src.charAt(pos));break;  
                }  
            }  
        }  
        return result.toString();  
    }  
      
//反过滤特殊字符  
    public static String decoding(String src){  
        if (src==null)  
            return "";  
        String result=src;  
        result=result.replace("&quot;", "\"").replace("&apos;", "\'");  
        result=result.replace("&lt;", "<").replace("&gt;", ">");  
        result=result.replace("&amp;", "&");  
        result=result.replace("&pc;", "%").replace("&ul", "_");  
        result=result.replace("&shap;", "#").replace("&ques", "?");  
        return result;  
    }  
 
/**  
    *判断任意一个整数是否素数  
    *@paramn  
    *@return boolean  
    */   
    public boolean isPrimes(int n)   
    {   
      for (int i = 2; i <= Math.sqrt(n); i++) {   
          if(n%i==0)   
          {   
              return false;   
          }   
      }   
      return true;   
    }  

常用的java函数(三)数据库连接
/* * Db.java 
Created on 2007年8月20日, 上午 8:37 
*/ 
import java.io.*;  
import java.sql.*;  
import java.util.Properties;  
public class Db {  
    private String driver;  
    private String url;  
    private String user;  
    private String password;  
    private Connection conn;  
    private Statement stm;  
    private ResultSet rs;  
    public Db(){  
        this("DBConf.properties");  
    }  
    public Db(String conf) {  
        loadProperties(conf);  
        setConn();  
    }  
    public Connection getConn(){  
        return this.conn;  
    }  
  //handle the properties file to get the informations for connection  
    private void loadProperties(String conf){  
        Properties props = new Properties();  
        try {  
            props.load(new FileInputStream(conf));  
        } catch (FileNotFoundException e) {  
            e.printStackTrace();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
        this.driver = props.getProperty("driver");  
        this.url = props.getProperty("url");  
        this.user = props.getProperty("user");  
        this.password = props.getProperty("password");  
    }  
    //implement the Connection  
    private void setConn(){  
        try {  
            Class.forName(driver);  
            this.conn = DriverManager.getConnection(url,user,password);  
        } catch(ClassNotFoundException classnotfoundexception) {  
              classnotfoundexception.printStackTrace();  
            System.err.println("db: " + classnotfoundexception.getMessage());  
        } catch(SQLException sqlexception) {  
            System.err.println("db.getconn(): " + sqlexception.getMessage());  
        }  
    }  
       public void doInsert(String sql) {  
        try {  
            Statement statement = conn.createStatement();  
            int i = stm.executeUpdate(sql);  
        } catch(SQLException sqlexception) {  
            System.err.println("db.executeInset:" + sqlexception.getMessage());  
        }  
    }  
    public void doDelete(String sql) {  
        try {  
            stm = conn.createStatement();  
            int i = stm.executeUpdate(sql);  
        } catch(SQLException sqlexception) {  
            System.err.println("db.executeDelete:" + sqlexception.getMessage());  
        }  
    }  
    public void doUpdate(String sql) {  
        try {  
            stm = conn.createStatement();  
            int i = stm.executeUpdate(sql);  
        } catch(SQLException sqlexception) {  
            System.err.println("db.executeUpdate:" + sqlexception.getMessage());  
        }  
    }  
      
    public ResultSet doSelect(String sql) {  
        try {  
            stm = conn.createStatement(java.sql.ResultSet.TYPE_SCROLL_INSENSITIVE,java.sql.ResultSet.CONCUR_READ_ONLY);  
            rs = stm.executeQuery(sql);  
        } catch(SQLException sqlexception) {  
            System.err.println("db.executeQuery: " + sqlexception.getMessage());  
        }  
        return rs;  
    }  
    public static void main(String[] args){  
        try{  
            Db db = new Db();  
            Connection conn = db.getConn();  
            if(conn != null && !conn.isClosed()) {  
                System.out.println("連結成功");  
                ResultSet rs = db.doSelect("select * from content");  
                while(rs.next()){  
                    System.out.println(rs.getString(1)+":"+rs.getString(2)+":"+rs.getString(3));  
                  }  
                rs.close();  
                conn.close();  
            }  
        }catch(SQLException e) {  
            e.printStackTrace();  
        }  
    }    

常用的java函数(四)中文转拼音
/** 
 * <p> 
 * Title:  
 * Description:中文转换为拼音 
 * @version 1.0 
 */ 
public class ChineseSpelling {  
 
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" };  
 
private StringBuilder buffer;  
 
private String resource;  
 
private static ChineseSpelling chineseSpelling = new ChineseSpelling();  
 
public static ChineseSpelling getInstance() {  
return chineseSpelling;  
}  
 
public String getResource() {  
return resource;  
}  
 
public void setResource(String resource) {  
        this.resource = resource;  
}  
 
private int getChsAscii(String chs) {  
int asc = 0;  
try {  
 
byte[] bytes = chs.getBytes("gb2312");  
 
if (bytes == null || bytes.length > 2 || bytes.length <= 0) { // 错误  
 
// log  
 
throw new RuntimeException("illegal resource string");  
// System.out.println("error");  
 
}  
if (bytes.length == 1) { // 英文字符  
 
                asc = bytes[0];  
}  
if (bytes.length == 2) { // 中文字符  
 
int hightByte = 256 + bytes[0];  
int lowByte = 256 + bytes[1];  
                asc = (256 * hightByte + lowByte) - 256 * 256;  
}  
} catch (Exception e) {  
            System.out.println("ERROR:ChineseSpelling.class-getChsAscii(String chs)" + e);  
// e.printStackTrace();  
 
}  
return asc;  
}  
 
public String convert(String str) {  
        String result = null;  
int ascii = getChsAscii(str);  
// System.out.println(ascii);  
 
if (ascii > 0 && ascii < 160) {  
            result = String.valueOf((char) ascii);  
} else {  
for (int i = (pyvalue.length - 1); i >= 0; i--) {  
if (pyvalue[i] <= ascii) {  
                    result = pystr[i];  
break;  
}  
}  
}  
return result;  
}  
 
public String getSelling(String chs) {  
        String key, value;  
        buffer = new StringBuilder();  
for (int i = 0; i < chs.length(); i++) {  
            key = chs.substring(i, i + 1);  
if (key.getBytes().length == 2) {  
                value = (String) convert(key);  
if (value == null) {  
                    value = "unknown";  
}  
} else {  
                value = key;  
}  
 
            buffer.append(value);  
}  
return buffer.toString();  
}  
 
public String getSpelling() {  
return this.getSelling(this.getResource());  
}  
 
public static void main(String[] args) {  
// ChineseSpelling finder = new ChineseSpelling();  
 
 
        ChineseSpelling finder = ChineseSpelling.getInstance();  
        finder.setResource("中文字符");  
        System.out.println(finder.getSpelling());  
        System.out.println(finder.getSelling("英文字符Eng"));  
}  
 

常用的java函数(五)人民币转成大写
/** 
    * 人民币转成大写 
    *  
    * @param value 
    * @return String 
    */ 
   public static String hangeToBig(double value)  
   {  
       char[] hunit = { '拾', '佰', '仟' }; // 段内位置表示  
       char[] vunit = { '万', '亿' }; // 段名表示  
       char[] digit = { '零', '壹', '贰', '叁', '肆', '伍', '陆', '柒', '捌', '玖' }; // 数字表示  
       long midVal = (long) (value * 100); // 转化成整形  
       String valStr = String.valueOf(midVal); // 转化成字符串  
 
       String head = valStr.substring(0, valStr.length() - 2); // 取整数部分  
       String rail = valStr.substring(valStr.length() - 2); // 取小数部分  
 
       String prefix = ""; // 整数部分转化的结果  
       String suffix = ""; // 小数部分转化的结果  
       // 处理小数点后面的数  
       if (rail.equals("00"))  
       { // 如果小数部分为0  
           suffix = "整";  
       }  
       else 
       {  
           suffix = digit[rail.charAt(0) - '0'] + "角" + digit[rail.charAt(1) - '0'] + "分"; // 否则把角分转化出来  
       }  
       // 处理小数点前面的数  
       char[] chDig = head.toCharArray(); // 把整数部分转化成字符数组  
       char zero = '0'; // 标志'0'表示出现过0  
       byte zeroSerNum = 0; // 连续出现0的次数  
       for (int i = 0; i < chDig.length; i++)  
       { // 循环处理每个数字  
           int idx = (chDig.length - i - 1) % 4; // 取段内位置  
           int vidx = (chDig.length - i - 1) / 4; // 取段位置  
           if (chDig[i] == '0')  
           { // 如果当前字符是0  
               zeroSerNum++; // 连续0次数递增  
               if (zero == '0')  
               { // 标志  
                   zero = digit[0];  
               }  
               else if (idx == 0 && vidx > 0 && zeroSerNum < 4)  
               {  
                   prefix += vunit[vidx - 1];  
                   zero = '0';  
               }  
               continue;  
           }  
           zeroSerNum = 0; // 连续0次数清零  
           if (zero != '0')  
           { // 如果标志不为0,则加上,例如万,亿什么的  
               prefix += zero;  
               zero = '0';  
           }  
           prefix += digit[chDig[i] - '0']; // 转化该数字表示  
           if (idx > 0)  
               prefix += hunit[idx - 1];  
           if (idx == 0 && vidx > 0)  
           {  
               prefix += vunit[vidx - 1]; // 段结束位置应该加上段名如万,亿  
           }  
       }  
 
       if (prefix.length() > 0)  
           prefix += '圆'; // 如果整数部分存在,则有圆的字样  
       return prefix + suffix; // 返回正确表示 
常用的java函数(六)异常处理类
/** 
 * (#)ThrowableManager.java    1.0    Apr 10, 2008 
 *  
 * Copyright 2007- wargrey , Inc. All rights are reserved. 
 */ 
package net.wargrey.application;  
 
import java.awt.Component;  
import javax.swing.JOptionPane;  
 
/** 
 * This class <code>ExceptionManager</code> and its subclasses are a form of  
 * <code>Exception</code>. It is used to wrap all the <code>Throwable</code> instances 
 * and handle them in a unified way. It will show the information which consists of  
 * StackTraces and Messages by using JOptionPanel. 
 *  
 * @author Estelle 
 * @version 1.0 
 * @see java.lang.Exception 
 * @since jdk 1.5 
 */ 
public class ExceptionManager extends Exception {  
      
    /** 
     * This field <code>alerter</code> is used to show the information the Class offered. 
     *  
     * @see javax.swing.JOptionPane 
     */ 
    private JOptionPane alerter;  
      
    /** 
     * This static method create an instance of the ExceptionManager by invoking the  
     * constructor <code>ExceptionManager(String msg)</code>. 
     *  
     * @param msg    The message will pass the specified constructor 
     * @return    An instance of the ExceptionManager created by invoking the constructor 
     *             <code>ExceptionManager(String msg)</code>. 
     */ 
    public static ExceptionManager wrap(String msg){  
        return new ExceptionManager(msg);  
    }  
      
    /** 
     * This static method create an instance of the ExceptionManager by invoking the  
     * constructor <code>ExceptionManager(Throwable throwable)</code>. 
     *  
     * @param throwable        The cause will pass the specified constructor 
     * @return    An instance of the ExceptionManager created by invoking the constructor 
     *             <code>ExceptionManager(Throwable throwable)</code>. 
     */ 
    public static ExceptionManager wrap(Throwable throwable){  
        return new ExceptionManager(throwable);  
    }  
      
    /** 
     * This static method create an instance of the ExceptionManager by invoking the  
     * constructor <code>ExceptionManager(String msg,Throwable throwable)</code>.  
     *  
     * @param msg            The message will pass the specified constructor 
     * @param throwable        The cause will pass the specified constructor 
     * @return    An instance of the ExceptionManager created by invoking the constructor 
     *             <code>ExceptionManager(String msg, Throwable throwable)</code> 
     */ 
    public static ExceptionManager wrap(String msg,Throwable throwable){  
        return new ExceptionManager(msg,throwable);  
    }  
      
    /** 
     * Constructs a new instance with the specified detail message. The concrete handler  
     * is its super class. This constructor always used to construct a custom exception 
     * not wrapping the exist exception. 
     *  
     * @param msg        the detail message which is the part of the information will be 
     *                     shown. 
     */ 
    public ExceptionManager(String msg){  
        super(msg);  
    }  
      
    /** 
     * Constructs a new instance with the specified detail cause. The concrete handler  
     * is its super class. This constructor always used to wrap an exist exception. 
     *  
     * @param throwable        the cause which has been caught. It's detail message and  
     *                         stacktrace are the parts the information will be shown. 
     */ 
    public ExceptionManager(Throwable throwable){  
        super(throwable);  
    }  
      
    /** 
     * Constructs a new instance with the specified detail message and cause. The  
     * concrete handler is its super class. This constructor always used to construct 
     * an exception wrapping the exist exception but requires a custom message.  
     *  
     * @param msg        the detail message which is the part of the information will  
     *                     be shown. 
     * @param throwable    the cause which has been caught. It's stacktrace is the parts 
     *                     the information will be shown. 
     */ 
    public ExceptionManager(String msg,Throwable throwable){  
        super(msg,throwable);  
    }  
      
    /** 
     * Show the information with everything is default. 
     */ 
    public synchronized void alert(){  
        alert((Component)null);  
    }  
      
    /** 
     * Show the information in a dialog with the specified title  
     * "ThrowableManager Alerter". The dialog belongs to the given component which  
     * default is the screen.  
     *  
     * @param parent    The component cause the exception. 
     */ 
    public synchronized void alert(Component parent){  
        alert(parent,"ThrowableManager Alerter");  
    }  
      
    /** 
     * Show the information in a dialog with the specified title. 
     *  
     * @param title        The title of the dialog. 
     */ 
    public synchronized void alert(String title){  
        alert((Component)null,title);  
    }  
      
    /** 
     * Show the information in a dialog which has the specified title and belongs to the 
     * specified component. 
     *  
     * @param parent    The component cause the exception. 
     * @param title        The title of the dialog. 
     */ 
    public synchronized void alert(Component parent,String title){  
        StringBuilder errorMessage=new StringBuilder();  
        errorMessage.append(this.toString());  
        for (StackTraceElement st:((this.getCause()==null)?this:this.getCause()).getStackTrace()){  
            errorMessage.append("\n\t     at ");  
            errorMessage.append(st.toString());  
        }          
        alerter.showMessageDialog(parent, errorMessage, title ,JOptionPane.ERROR_MESSAGE);  
    }  

常用的java函数(七)各类数据库连接
MySQL:      
    String Driver="com.mysql.jdbc.Driver";    //驱动程序  
    String URL="jdbc:mysql://localhost:3306/db_name";    //连接的URL,db_name为数据库名      
    String Username="username";    //用户名  
    String Password="password";    //密码  
    Class.forName(Driver).new Instance();  
    Connection con=DriverManager.getConnection(URL,Username,Password);  
Microsoft SQL Server 2.0驱动(3个jar的那个):  
    String Driver="com.microsoft.jdbc.sqlserver.SQLServerDriver";    //连接SQL数据库的方法  
    String URL="jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=db_name";    //db_name为数据库名  
    String Username="username";    //用户名  
    String Password="password";    //密码  
    Class.forName(Driver).new Instance();    //加载数据可驱动  
    Connection con=DriverManager.getConnection(URL,UserName,Password);    //  
Microsoft SQL Server 3.0驱动(1个jar的那个): // 老紫竹完善  
    String Driver="com.microsoft.sqlserver.jdbc.SQLServerDriver";    //连接SQL数据库的方法  
    String URL="jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=db_name";    //db_name为数据库名  
    String Username="username";    //用户名  
    String Password="password";    //密码  
    Class.forName(Driver).new Instance();    //加载数据可驱动  
    Connection con=DriverManager.getConnection(URL,UserName,Password);    //  
Sysbase:  
    String Driver="com.sybase.jdbc.SybDriver";    //驱动程序  
    String URL="jdbc:Sysbase://localhost:5007/db_name";    //db_name为数据可名  
    String Username="username";    //用户名  
    String Password="password";    //密码  
    Class.forName(Driver).newInstance();      
    Connection con=DriverManager.getConnection(URL,Username,Password);  
Oracle(用thin模式):  
    String Driver="oracle.jdbc.driver.OracleDriver";    //连接数据库的方法  
    String URL="jdbc:oracle:thin:@loaclhost:1521:orcl";    //orcl为数据库的SID  
    String Username="username";    //用户名  
    String Password="password";    //密码  
    Class.forName(Driver).newInstance();    //加载数据库驱动  
    Connection con=DriverManager.getConnection(URL,Username,Password);      
PostgreSQL:  
    String Driver="org.postgresql.Driver";    //连接数据库的方法  
    String URL="jdbc:postgresql://localhost/db_name";    //db_name为数据可名  
    String Username="username";    //用户名  
    String Password="password";    //密码  
    Class.forName(Driver).newInstance();      
    Connection con=DriverManager.getConnection(URL,Username,Password);  
DB2:  
    String Driver="com.ibm.db2.jdbc.app.DB2.Driver";    //连接具有DB2客户端的Provider实例  
    //String Driver="com.ibm.db2.jdbc.net.DB2.Driver";    //连接不具有DB2客户端的Provider实例  
    String URL="jdbc:db2://localhost:5000/db_name";    //db_name为数据可名  
    String Username="username";    //用户名  
    String Password="password";    //密码  
    Class.forName(Driver).newInstance();      
    Connection con=DriverManager.getConnection(URL,Username,Password);  
Informix:  
    String Driver="com.informix.jdbc.IfxDriver";      
    String URL="jdbc:Informix-sqli://localhost:1533/db_name:INFORMIXSER=myserver";    //db_name为数据可名  
    String Username="username";    //用户名  
    String Password="password";    //密码  
    Class.forName(Driver).newInstance();      
    Connection con=DriverManager.getConnection(URL,Username,Password);  
JDBC-ODBC:  
    String Driver="sun.jdbc.odbc.JdbcOdbcDriver";  
    String URL="jdbc:odbc:dbsource";    //dbsource为数据源名  
    String Username="username";    //用户名  
    String Password="password";    //密码  
    Class.forName(Driver).newInstance();      
    Connection con=DriverManager.getConnection(URL,Username,Password);
常用的java函数(八)TXT转XML
/* 
  *txt转换xml  
  */ 
import java.io.BufferedReader;  
import java.io.BufferedWriter;  
import java.io.FileReader;  
import java.io.FileWriter;  
import java.util.StringTokenizer;  
 
public class TxtToXml {  
 private String strTxtFileName;  
 
 private String strXmlFileName;  
 
 public TxtToXml() {  
  strTxtFileName = new String();  
  strXmlFileName = new String();  
 }  
 
 public void createXml(String strTxt, String strXml) {  
  strTxtFileName = strTxt;  
  strXmlFileName = strXml;  
  String strTmp;  
  try {  
   BufferedReader inTxt = new BufferedReader(new FileReader(  
     strTxtFileName));  
   BufferedWriter outXml = new BufferedWriter(new FileWriter(  
     strXmlFileName));  
   outXml.write("<?xml version= \"1.0\" encoding=\"gb2312\"?>");  
   outXml.newLine();  
   outXml.write("<people>");  
   while ((strTmp = inTxt.readLine()) != null) {  
    StringTokenizer strToken = new StringTokenizer(strTmp, ",");  
    String arrTmp[];  
    arrTmp = new String[3];  
    for (int i = 0; i < 3; i++)  
     arrTmp[i] = new String("");  
    int index = 0;  
    outXml.newLine();  
    outXml.write("    <students>");  
    while (strToken.hasMoreElements()) {  
     strTmp = (String) strToken.nextElement();  
     strTmp = strTmp.trim();  
     arrTmp[index++] = strTmp;  
    }  
    outXml.newLine();  
    outXml.write("        <name>" + arrTmp[0] + "</name>");  
    outXml.newLine();  
    outXml.write("        <sex>" + arrTmp[1] + "</sex>");  
    outXml.newLine();  
    outXml.write("        <age>" + arrTmp[2] + "</age>");  
    outXml.newLine();  
    outXml.write("    </students>");  
   }  
   outXml.newLine();  
   outXml.write("</people>");  
   outXml.flush();  
  } catch (Exception e) {  
   e.printStackTrace();  
  }  
 }  
 
 public static void main(String[] args) {  
  String txtName = "testtxt.txt";  
  String xmlName = "testxml.xml";  
  TxtToXml thisClass = new TxtToXml();  
  thisClass.createXml(txtName, xmlName);  
 }  

常用的java函数(九)时间计算函数
import java.text.DecimalFormat;  
import java.util.Arrays;  
 
/** 
 * 时间计算工具类 
 */ 
public class Time {  
 
    /** 
     * 时间字段常量,表示“秒” 
      */ 
    public final static int SECOND = 0;  
      
    /** 
     * 时间字段常量,表示“分” 
      */ 
    public final static int MINUTE = 1;  
      
    /** 
     * 时间字段常量,表示“时” 
      */ 
    public final static int HOUR = 2;  
      
    /** 
     * 时间字段常量,表示“天” 
      */ 
    public final static int DAY = 3;  
 
    /** 
     * 各常量允许的最大值 
      */ 
    private final int[] maxFields = { 59, 59, 23, Integer.MAX_VALUE - 1 };  
      
    /** 
     * 各常量允许的最小值 
      */ 
    private final int[] minFields = { 0, 0, 0, Integer.MIN_VALUE };  
      
    /** 
     * 默认的字符串格式时间分隔符 
      */ 
    private String timeSeparator = ":";  
      
    /** 
     * 时间数据容器 
      */ 
    private int[] fields = new int[4];      
      
    /** 
     * 无参构造,将各字段置为 0 
     */ 
    public Time() {  
        this(0, 0, 0, 0);  
    }  
 
    /** 
     * 使用时、分构造一个时间 
      * @param hour      小时 
      * @param minute    分钟 
      */ 
    public Time(int hour, int minute) {  
        this(0, hour, minute, 0);  
    }  
 
    /** 
     * 使用时、分、秒构造一个时间 
      * @param hour      小时 
      * @param minute    分钟 
      * @param second    秒 
      */ 
    public Time(int hour, int minute, int second) {  
        this(0, hour, minute, second);  
    }  
      
    /** 
     * 使用一个字符串构造时间<br/> 
     * Time time = new Time("14:22:23"); 
     * @param time      字符串格式的时间,默认采用“:”作为分隔符 
      */ 
    public Time(String time) {          
        this(time, null);  
    }  
 
    /** 
     * 使用天、时、分、秒构造时间,进行全字符的构造 
      * @param day       天 
      * @param hour      时 
      * @param minute    分 
      * @param second    秒 
      */ 
    public Time(int day, int hour, int minute, int second) {  
        set(DAY, day);  
        set(HOUR, hour);  
        set(MINUTE, minute);  
        set(SECOND, second);  
    }    
      
    /** 
     * 使用一个字符串构造时间,指定分隔符<br/> 
     * Time time = new Time("14-22-23", "-"); 
     * @param time      字符串格式的时间 
      */ 
    public Time(String time, String timeSeparator) {  
        if(timeSeparator != null) {  
            setTimeSeparator(timeSeparator);  
        }  
        String pattern = patternQuote(this.timeSeparator);  
        String matcher = new StringBuffer()  
                                .append("\\d+?").append(pattern)  
                                .append("\\d+?").append(pattern)  
                                .append("\\d+?")  
                                .toString();  
        if(!time.matches(matcher)) {  
            throw new IllegalArgumentException(time + ", time format error, HH" 
                    + this.timeSeparator + "mm" + this.timeSeparator + "ss");  
        }          
        String[] times = time.split(pattern);  
        set(DAY, 0);  
        set(HOUR, Integer.parseInt(times[0]));  
        set(MINUTE, Integer.parseInt(times[1]));  
        set(SECOND, Integer.parseInt(times[2]));  
    }  
      
    /** 
     * 设置时间字段的值 
     * @param field     时间字段常量 
     * @param value     时间字段的值 
     */ 
    public void set(int field, int value) {          
        if(value < minFields[field]) {  
            throw new IllegalArgumentException(value +  
                    ", time value must be positive.");  
        }  
        fields[field] = value % (maxFields[field] + 1);  
        // 进行进位计算  
         int carry = value / (maxFields[field] + 1);  
        if(carry > 0) {  
            int upFieldValue = get(field + 1);  
            set(field + 1, upFieldValue + carry);  
        }  
    }  
 
    /** 
     * 获得时间字段的值 
      * @param field     时间字段常量 
      * @return          该时间字段的值 
      */ 
    public int get(int field) {  
        if(field < 0 || field > fields.length - 1) {  
            throw new IllegalArgumentException(field + ", field value is error.");  
        }  
        return fields[field];  
    }  
 
    /** 
     * 将时间进行“加”运算,即加上一个时间 
      * @param time      需要加的时间 
      * @return          运算后的时间 
      */ 
    public Time addTime(Time time) {  
        Time result = new Time();  
        int up = 0;     // 进位标志  
         for (int i = 0; i < fields.length; i++) {  
            int sum = fields[i] + time.fields[i] + up;  
            up = sum / (maxFields[i] + 1);  
            result.fields[i] = sum % (maxFields[i] + 1);  
        }  
        return result;  
    }  
 
    /** 
     * 将时间进行“减”运算,即减去一个时间 
      * @param time      需要减的时间 
      * @return          运算后的时间 
      */ 
    public Time subtractTime(Time time) {  
        Time result = new Time();  
        int down = 0;       // 退位标志  
         for (int i = 0, k = fields.length - 1; i < k; i++) {  
            int difference = fields[i] + down;  
            if (difference >= time.fields[i]) {  
                difference -= time.fields[i];  
                down = 0;  
            } else {  
                difference += maxFields[i] + 1 - time.fields[i];  
                down = -1;  
            }  
            result.fields[i] = difference;  
        }  
        result.fields[DAY] = fields[DAY] - time.fields[DAY] + down;  
        return result;  
    }  
      
    /** 
     * 获得时间字段的分隔符 
      * @return 
     */ 
    public String getTimeSeparator() {  
        return timeSeparator;  
    }  
 
    /** 
     * 设置时间字段的分隔符(用于字符串格式的时间) 
      * @param timeSeparator     分隔符字符串 
      */ 
    public void setTimeSeparator(String timeSeparator) {  
        this.timeSeparator = timeSeparator;  
    }  
 
    /** 
     * 正则表达式引用处理方法,源自 JDK @link java.util.regex.Pattern#quote(String) 
     */ 
    private String patternQuote(String s) {  
        int slashEIndex = s.indexOf("\\E");  
        if (slashEIndex == -1)  
            return "\\Q" + s + "\\E";  
 
        StringBuilder sb = new StringBuilder(s.length() * 2);  
        sb.append("\\Q");  
        slashEIndex = 0;  
        int current = 0;  
        while ((slashEIndex = s.indexOf("\\E", current)) != -1) {  
            sb.append(s.substring(current, slashEIndex));  
            current = slashEIndex + 2;  
            sb.append("\\E\\\\E\\Q");  
        }  
        sb.append(s.substring(current, s.length()));  
        sb.append("\\E");  
        return sb.toString();  
    }  
 
    public String toString() {  
        DecimalFormat df = new DecimalFormat("00");  
        return new StringBuffer().append(fields[DAY]).append(", ")  
                    .append(df.format(fields[HOUR])).append(timeSeparator)  
                    .append(df.format(fields[MINUTE])).append(timeSeparator)  
                    .append(df.format(fields[SECOND]))  
                    .toString();  
    }  
 
    public int hashCode() {  
        final int PRIME = 31;  
        int result = 1;  
        result = PRIME * result + Arrays.hashCode(fields);  
        return result;  
    }  
 
    public boolean equals(Object obj) {  
        if (this == obj)  
            return true;  
        if (obj == null)  
            return false;  
        if (getClass() != obj.getClass())  
            return false;  
        final Time other = (Time) obj;  
        if (!Arrays.equals(fields, other.fields)) {  
            return false;  
        }  
        return true;  
    }  

常用的java函数(十)随机函数
/**  
 * @author talent_marquis<��˺��>  
 * Email: talent_marquis@163.com  
 * Copyright (C) 2007 talent_marquis<��˺��>  
 * All rights reserved.  
 */  
package com.dextrys.trilogy.util;  
 
import java.util.Arrays;  
 
import org.eclipse.swt.graphics.RGB;  
 
public class RandomUtil  
{  
 
    /** 
     * @param args 
     */ 
    public static void main( String[] args )  
    {  
        //System.out.println( getRandomNormalString( 8 ) );  
        int[] test = getRandomIntWithoutReduplicate( 0, 40, 39 );  
        Arrays.sort( test );  
        for( int i : test )  
        {  
            System.out.println( i );  
        }  
    }  
 
    /** 
     * get a integer array filled with random integer without reduplicate [min, max) 
     * @param min    the minimum value 
     * @param max the maximum value 
     * @param size the capacity of the array 
     * @return a integer array filled with random integer without redupulicate 
     */ 
    public static int[] getRandomIntWithoutReduplicate( int min, int max, int size )  
    {  
        int[] result = new int[size];  
          
        int arraySize = max - min;  
        int[] intArray = new int[arraySize];  
        // init intArray  
        for( int i = 0 ; i < intArray.length ; i++ )  
        {  
            intArray[i] = i + min;  
        }  
        // get randome interger without reduplicate  
        for( int i = 0 ; i < size ; i++ )  
        {  
            int c = getRandomInt( min, max - i );  
            int index = c - min;  
            swap( intArray, index, arraySize - 1 - i );  
            result[i] = intArray[ arraySize - 1 - i ];  
        }  
                  
        return result;  
    }  
      
    private static void swap( int[] array, int x, int y )  
    {  
        int temp = array[x];  
        array[x] = array[y];  
        array[y] = temp;  
    }  
      
    /** 
     * get a random Integer with the range [min, max) 
     * @param min the minimum value 
     * @param max the maximum value 
     * @return the random Integer value 
     */ 
    public static int getRandomInt( int min, int max )  
    {  
        // include min, exclude max  
        int result = min + new Double( Math.random() * ( max - min ) ).intValue();  
 
        return result;  
    }  
 
    /** 
     * get a random double with the range [min, max) 
     * @param min the minimum value 
     * @param max the maximum value 
 

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