一些工具

JAVA生成随机验证码

一、要求生成随机八位的验证码

二、4个数字在前，4个字母在后

三、字母包含大小写

package operator;

import java.util.Random;

public class day01 {
    public static void main(String[] args) {
        //大小写字母合计为52位
        char[] xianyufanshen = new char[52];
        //index表示要操作的那个索引
        int index = 0;
        for (int i = 'A'; i <= 'Z'; i++) {
            //i 表示 ‘A’ ~ ‘Z’ 之间的字符所对应的数字
            xianyufanshen[index] = (char) i;
            index++;
        }
        //当循环结束之后，数组中存了A-Z
        for (int i = 'a'; i <= 'z'; i++) {
            //i 表示 ‘a’ ~ ‘z’ 之间的字符所对应的数字
            xianyufanshen[index] = (char) i;
            index++;
        }
        Random r = new Random();
        //随机生成四个0-9之间的随机数。
        for (int i = 0; i < 4; i++) {
            int randomNumber = r.nextInt(10);
            System.out.print(randomNumber);
        }
        //随机生成4个大小写字母
        for (int i = 0; i < 4; i++) {
            int randomIndex = r.nextInt(xianyufanshen.length);
            char randomChar = xianyufanshen[randomIndex];
            System.out.print(randomChar);
        }


    }
}

验证数组是否为空

public static boolean arrayValid(Object[] objects) {
	if (objects != null && objects.length > 0) {
		return true;
	} else {
		return false;
	}
}

验证list是否为空

public boolean listValid(List list) {
	if (list != null && list.size() > 0) {
		return true;
	} else {
		return false;
	}
}
  

获得年龄

  public int age(String dateStart, String dateEnd) throws Exception{
	  int yearStart = Integer.parseInt(dateStart.substring(0,4));
	  int yearEnd = Integer.parseInt(dateEnd.substring(0,4));
	  return yearEnd-yearStart;
  }

是否为奇数

  public boolean isOdd(int i){
	  if(i%2==0){
		  return false;
	  }else{
		  return true;
	  }
  }

返回固定长度串，空白地方用空格填充

  public String fixSpaceStr(String str,int len){
	  StringBuffer sBuf = new StringBuffer();
	  try{
		  if(str.length()>len){
			  return str;
		  }else{
			  sBuf.append(str);
			  for(int i=0;i<(len-str.length());i++){
				  sBuf.append(" ");
			  }
			  return sBuf.toString();
		  }
	  }catch(Exception e){
		  return str;
	  }
  }
  public String fixSpaceStr(int number,int len){
	  return fixSpaceStr(String.valueOf(number),len);
  }
  

前缀空格

  public String prefixSpaceStr(String str,int len){
	  StringBuffer sBuf = new StringBuffer();
	  try{
		  if(str.length()>len){
			  return str;
		  }else{
			  for(int i=0;i<(len-str.length());i++){
				  sBuf.append(" ");
			  }
			  sBuf.append(str);
			  return sBuf.toString();
		  }
	  }catch(Exception e){
		  return str;
	  }
  }

截取字符,如果超过长度,截取并加省略号

  public String suspensionStr(String str,int len){
	  try{
		  str = str.substring(0,len) + "...";
	  }catch(Exception e){
		  return str;
	  }
	  return str;
  }

url get方式传递参数

  public static String joinUrlParameter(List<String> sList){
	  StringBuffer sBuf = new StringBuffer();
	  for(Iterator it = sList.iterator(); it.hasNext();){
		  sBuf.append("&").append(it.next()).append("=").append(it.next());
	  }
	  return sBuf.substring(1, sBuf.length());	//去掉第一个&符号
  }
  

字符串返回分割后的数组

  static public String[] splitStr(String str,String SplitFlag){
    int i =0;
    try{
      StringTokenizer st = new StringTokenizer(str, SplitFlag);
      String tokens[] = new String[st.countTokens()];  
      while (st.hasMoreElements()) {
        tokens[i] = st.nextToken();
        i++;
      }
      return tokens;
    }catch(Exception e){
      return null;
    }
  }

阶梯函数,例如，a,b,c 返回 a; a,b; a,b,c

  static public String[] splitStair(String str,String SplitFlag){
	  try{
		  String[] _temp = splitStr(str, SplitFlag);
		  for(int i=1;i<_temp.length;i++){
			  _temp[i] = _temp[i-1]+SplitFlag+_temp[i];
		  }
		  return _temp;
	  }catch(Exception e){
		  return null;
	  }
  }

将数组合并为一个字符串

输入参数：String aStr 要合并数组

输入参数：String SplitFlag 设置分割字符

输出参数：String 要合并数组

  static public String joinStr(String[] aStr,String SplitFlag){
    StringBuffer sBuffer = new StringBuffer();
    if (aStr != null){
      for (int i=0;i<aStr.length;i++){
        sBuffer.append(aStr[i]).append(SplitFlag);
      }
      sBuffer.delete(sBuffer.length() - 1, sBuffer.length()); //去掉最后的分隔符 SplitFlag
    }else{
      sBuffer = sBuffer.append("");
    }
    return sBuffer.toString();
  }

将数组合并为一个字符串

String sPrefix 数组元素加的前缀

String sSuffix 数组元素加的后缀

String SplitFlag 设置分割字符

String 合并后的字符串

  static public String joinStr(String[] aStr,String sPrefix,String sSuffix,String SplitFlag){
    StringBuffer sBuffer = new StringBuffer();
    if (aStr != null){
      for (int i=0;i<aStr.length;i++){
        sBuffer.append(sPrefix).append(aStr[i]).append(sSuffix).append(SplitFlag);
      }
      sBuffer.delete(sBuffer.length() - SplitFlag.length(), sBuffer.length()); //去掉最后的分隔符 SplitFlag
    }else{
      sBuffer = sBuffer.append("");
    }
    return sBuffer.toString();
  }
  

数组返回用于in查询的串 ‘x’,‘y’

  static public String joinInStr(String[] aStr){
	  StringBuffer sBuffer = new StringBuffer();
	  if (aStr != null){
		  for (int i=0;i<aStr.length;i++){
			  sBuffer.append("'").append(aStr[i]).append("'").append(",");
		  }
		  sBuffer.delete(sBuffer.length() - 1, sBuffer.length());
	  }else{
		  sBuffer = sBuffer.append("");
	  }
	  return sBuffer.toString();
  }

返回系统时间

int style 设置返回系统时间样式

string 返回系统时间样式

存在问题：中文乱码，但JSP中显示正常。

  static public String SysTime(String strStyle){
    String s = "";
    if (strStyle.compareTo("")==0){
    	strStyle = "yyyy-MM-dd HH:mm:ss";	
    }
    Date date=new Date();
    SimpleDateFormat dformat=new SimpleDateFormat(strStyle);
    s = dformat.format(date);
    return s;
  }

  static public String sysTime(){
    String s = "";
    Date date=new Date();
    SimpleDateFormat dformat=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    s = dformat.format(date);
    return s;
  }

  static public String sysDate(){
    String s = "";
    Date date=new Date();
    SimpleDateFormat dformat=new SimpleDateFormat("yyyy-MM-dd");
    s = dformat.format(date);
    return s;
  }

是否为空

  public static boolean isNull(Object obj){
    try{
      if(obj==null){
    	  return true;
      }
      return false;
    }catch(Exception e){
      return false;
    }
  }
  
  public static boolean isNotNull(Object obj){
    try{
      if(obj==null){
    	  return false;
      }
      return true;
    }catch(Exception e){
      return true;
    }
  }  

  public static boolean isEmpty(String str){
    try{
      if(str==null || str.equals("null") || str.equals("")){
    	  return true;
      }
      return false;
    }catch(Exception e){
      return false;
    }
  }
  
  public static boolean isEmpty(String strs[]){
	  try{
		  if(strs==null || strs.length<=0){
			  return true;
		  }
		  return false;
	  }catch(Exception e){
		  return false;
	  }
  }

  public static boolean isNotEmpty(String str){
    try{
      if(str==null || str.equals("null") || str.equals("")){
    	  return false;
      }
      return true;
    }catch(Exception e){
      return true;
    }
  }

  public static boolean isNotEmpty(Object obj){
    try{
      if(obj==null || obj.toString().equals("null") || obj.toString().equals("")){
    	  return false;
      }
      return true;
    }catch(Exception e){
      return true;
    }
  }
  
  public static boolean isNotEmpty(List obj){
	  try{
		  if(obj==null || obj.size()<=0){
			  return false;
		  }
		  return true;
	  }catch(Exception e){
		  return true;
	  }
  }

用于转换为null的字段。

String strvalue 设置要转换的字符串

不为“null”的返回原串；为“null”返回""。

```java
  public static String convertNull(String strvalue)
  {
    try{
      if(strvalue.equals("null") || strvalue.length()==0){
        return "";
      }else{
        return strvalue.trim();
      }
    }catch(Exception e){
      return "";
    }
  }

  public static String[] convertNull(String[] aContent)
  {
    try{
      for(int i=0;i<aContent.length;i++){
        if(aContent[i].toLowerCase().compareTo("null")==0){
          aContent[i] = "";
        }
      }
      return aContent;
    }catch(Exception e){
      return null;
    }
  }
    
  public static String convertNull(Object o)
  {
    try{
      String strvalue = String.valueOf(o);
      if(strvalue.equals(null) || strvalue.equals("null") || strvalue.length()==0){
        return "";
      }else{
        return strvalue.trim();
      }
    }catch(Exception e){
      return "";
    }
  }

将为null的数据转为0，用在数值的值从数据库中读出的情况

  public static int ConvertZero(Object o)
  {
    try{
      String s = convertNull(o);
      if(s==""){
        return 0;
      }else{
        return Integer.parseInt(s);
      }
    }catch(Exception e){
      return 0;
    }
  }
`

``

将为null的数据转为0，用在数值的值从数据库中读出的情况

  public static int cvtPecrent(Object o)
  {
    try{
      String s = convertNull(o);
      if(s==""){
        return 0;
      }else{
        return Integer.parseInt(s);
      }
    }catch(Exception e){
      return 0;
    }
  }  
  

## if 0 then return "";
  public static String FormatZero(Object o)
  {
    try{
      String s = convertNull(o);
      if(s.compareTo("")==0){
        return "";
      }else{
        return String.valueOf(s);
      }
    }catch(Exception e){
      return "";
    }
  }

if 0 then return “”;

  public static String FormatZero(String s)
  {
    try{
      if(s.compareTo("0")==0){
        return "";
      }else{
        return s;
      }
    }catch(Exception e){
      return "";
    }

UrlEncoder 进行URL编码

public String UrlEncoder(String s)
{
String s1 = “”;
if(s == null)
return “”;
try
{
s1 = URLEncoder.encode(s);
}
catch(Exception e)
{
System.out.println(“URL Encoder :” + e.toString());
s1 = “”;
}
return s1;
}

URLDecoder 进行URL解码

   public String UrlDecoder(String s)
    {
        String s1 = "";
        if(s == null)
            return "";
        try
        {
            s1 = URLDecoder.decode(s);
        }
        catch(Exception e)
        {
            System.out.println("URL Encoder :" + e.toString());
            s1 = "";
        }
        return s1;
    }

将字符串转化成首字母大写，其余字母小写的格式

  public static String format_Aaa(String source) {

    if (source==null) return null;
    if (source.equals("")) return "";

    String a;
    a = source.substring(0, 1);
    a = a.toUpperCase();
    return a + source.substring(1);

  }

将字符串转换成Long型

  public static long parseLong(String param) {
    long l=0;
    try {
      l = Long.parseLong(param);
    }
    catch (Exception e) {
    }

    return l;
  }

将字符串转换成Float型

  public static float parseFloat(String param) {
    float l=0;
    try {
      l = Float.parseFloat(param);
    }
    catch (Exception e) {
    }

    return l;
  }

将字符串转换成Integer型

  public static int parseInt(String param) {
    int l=0;
    try {
      l = Integer.parseInt(param);
    }
    catch (Exception e) {
    }

    return l;
  }

将字符串转换成Double型

  public static double parseDouble(String param) {
    double l=0;
    try {
      l = Double.parseDouble(param);
    }
    catch (Exception e) {
    }

    return l;
  }

s是否存在ArrayList中，存在返回数组下标，不存在返回-1

  public static int existElements(String s,ArrayList aList) {
    try{
      for (int i = 0; i < aList.size(); i ++) {
        if (s.equals(aList.get(i))){
          return i;
        }
      }
    }catch(Exception e){   }
    return -1;
  }

s是否存在String数组中，存在返回数组下标，不存在返回-1

  public static int existElements(String s,String[] a) {
    try{
      for (int i = 0; i < a.length; i ++) {
        if (s.compareTo((a[i].trim()))==0){  
          return i;
        }
      }
    }catch(Exception e){   }
    return -1;
  }

判断对象o是否存在于set对象集合中

  public static boolean existElements(Object o, Set set) {
	  boolean isExists = false;
	  Iterator it = set.iterator();
	  while(it.hasNext())
	  {
	       Object obj = it.next();
	       if(o.equals(obj))
	       {
	    	   isExists=true;
	    	   break;
	       }
	  }
	  return isExists;
  }

s是否存在ArrayList中，存在返回数组下标，不存在返回-1

  public static int IsIndexOfElements(String s,ArrayList aList) {
    try{
      String s1 = "";
      for (int i = 0; i < aList.size(); i ++) {
        s1 = String.valueOf(aList.get(i));
        if (s1.indexOf(s)!=-1){
          return i;
        }
      }
    }catch(Exception e){   }
    return -1;
  }

将ArrayList转换为一维String数组，并把其中的null换成空字符串

  public String[] ArrayListToString(ArrayList aList) {
    String[] s = new String[aList.size()];
    for (int i = 0; i < aList.size(); i ++) {
      s[i] = this.convertNull(aList.get(i));
    }
    return s;
  }

将数组中的null换成空字符串

  public static void formatArrayList(ArrayList al) {

    for (int i = 0; i < al.size(); i ++) {
      if (al.get(i) == null)
        al.set(i, "");
    }

  }

StrToTimestamp 功能：将字符串转换为Timestamp 。

输入参数：String timestampStr 设置要转换的字符串 String pattern 要转换的format

输出参数：如果格式正确返回格式后的字符串。不正确返回系统日期。

  public static Timestamp StrToTimestamp(String timestampStr,String pattern) throws ParseException {
    Date date = null;
    SimpleDateFormat format = new SimpleDateFormat(pattern);
    try {
      date = format.parse(timestampStr);
    } catch (ParseException ex) {
      throw ex;
    }
    return date == null ? null : new Timestamp(date.getTime());
  }

  //ex:utilFuns.StrToDateTimeFormat("2005-12-01 00:00:00.0,"yyyy-MM-dd")
  public static String StrToDateTimeFormat(String timestampStr,String pattern) throws ParseException {
    String s ="";
    try{
      s = String.valueOf(StrToTimestamp(timestampStr, pattern));
      s = s.substring(0,pattern.length());
    }catch(Exception e){ }
    return s;
  }

  //ex:utilFuns.StrToDateTimeFormat("2005-12-01 00:00:00.0,"yyyy-MM-dd")
  public static String dateTimeFormat(Date date,String pattern) throws ParseException {
    String s ="";
    try{
        SimpleDateFormat dformat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        s = dformat.format(date);
        s = String.valueOf(StrToTimestamp(s, pattern));
        s = s.substring(0,pattern.length());
    }catch(Exception e){ }
    return s;
  }
  public static String dateTimeFormat(Date date) throws ParseException {
	  String s ="";
	  try{
		  SimpleDateFormat dformat = new SimpleDateFormat("yyyy-MM-dd");
		  s = dformat.format(date);
		  s = String.valueOf(StrToTimestamp(s, "yyyy-MM-dd"));
		  s = s.substring(0,"yyyy-MM-dd".length());
	  }catch(Exception e){ }
	  return s;
  }
  
  //add by tony 20100228 转换中文 格式必须为："yyyy-MM-dd HH:mm:ss"的一部分
  public static String formatDateTimeCN(String date) throws ParseException {
	  String s ="";
	  try{
		  if(UtilFuns.isEmpty(date)){
			  return "";
		  }
		  if(date.indexOf(".")>-1){
			  date = date.substring(0, date.indexOf("."));
		  }
		  if(date.length()==4){			//yyyy
			  s = date+"年";
		  }else if(date.length()==7){	//yyyy-MM
			  s = date.replaceAll("-0", "-").replaceFirst("-", "年")+"月";
		  }else if(date.length()==10){	//yyyy-MM-dd
			  s = date.replaceAll("-0", "-").replaceFirst("-", "年").replaceFirst("-", "月")+"日";
		  }else if(date.length()==2){	//HH
			  s = date+"时";
		  }else if(date.length()==5){	//HH:mm
			  s = date.replaceAll(":0", ":").replaceFirst(":", "时")+"分";
		  }else if(date.length()==8){	//HH:mm:ss
			  s = date.replaceAll(":0", ":").replaceFirst(":", "时").replaceFirst(":", "分")+"秒";
		  }else if(date.length()==13){	//yyyy-MM-dd HH
			  s = date.replaceAll("-0", "-").replaceFirst("-", "年").replaceFirst("-", "月").replaceAll(" 0", " ").replaceFirst(" ", "日")+"时";
		  }else if(date.length()==16){	//yyyy-MM-dd HH:mm
			  s = date.replaceAll("-0", "-").replaceFirst("-", "年").replaceFirst("-", "月").replaceAll(" 0", " ").replaceFirst(" ", "日").replaceAll(":0", ":").replaceFirst(":", "时")+"分";
		  }else if(date.length()==19){	//yyyy-MM-dd HH:mm:ss
			  s = date.replaceAll("-0", "-").replaceFirst("-", "年").replaceFirst("-", "月").replaceAll(" 0", " ").replaceFirst(" ", "日").replaceAll(":0", ":").replaceFirst(":", "时").replaceFirst(":", "分")+"秒";
		  }
		  s = s.replaceAll("0[时分秒]", "");	//正则 0时0分0秒的都替换为空
	  }catch(Exception e){ }
	  
	  return s;
  }
  
  //add by tony 2011-07-26 返回英文格式日期 oct.10.2011
  public static String formatDateEN(String date) throws ParseException {
	  String s ="";
	  int whichMonth = 1;
	  try{
		  if(UtilFuns.isEmpty(date)){
			  return "";
		  }
		  String[] aString = date.replaceAll("-0", "-").split("-");
		  whichMonth = Integer.parseInt(aString[1]);
		  if(whichMonth==1){
			  s = "Jan";
		  }else if(whichMonth==2){
			  s = "Feb";
		  }else if(whichMonth==3){
			  s = "Mar";
		  }else if(whichMonth==4){
			  s = "Apr";
		  }else if(whichMonth==5){
			  s = "May";
		  }else if(whichMonth==6){
			  s = "Jun";
		  }else if(whichMonth==7){
			  s = "Jul";
		  }else if(whichMonth==8){
			  s = "Aug";
		  }else if(whichMonth==9){
			  s = "Sept";
		  }else if(whichMonth==10){
			  s = "Oct";
		  }else if(whichMonth==11){
			  s = "Nov";
		  }else if(whichMonth==12){
			  s = "Dec";
		  }
		  s = s+"."+aString[2]+","+aString[0];
		  
	  }catch(Exception e){ }
	  
	  return s;
  }

  //返回年月格式 2010-7
  public String formatShortMonth(String strDate){
	  return strDate.substring(0,7).replaceAll("-0", "-");
  }
  
  //返回年月格式 2010-07
  public String formatMonth(String strDate){
	  return strDate.substring(0,7);
  }

删除最后1个字符

  public static String delLastChar(String s){
    try{
      if(s.length()>0){
        s = s.substring(0,s.length()-1);  
      }      
    }catch(Exception e){
      return "";
    }
    return s;
  }

删除最后len个字符

  public static String delLastChars(String s,int len){
    try{
      if(s.length()>0){
        s = s.substring(0,s.length()-len);  
      }      
    }catch(Exception e){
      return "";
    }
    return s;
  }
  

用于转换后几位的为*。

String strvalue 设置要转换的字符串

int Flag 位数。

 public static String getPassString( String strvalue, int Flag ) {
    try {
      if ( strvalue.equals("null") || strvalue.compareTo("")==0){
        return "";
      } else {
        int intStrvalue = strvalue.length();
        if ( intStrvalue > Flag ) {
          strvalue = strvalue.substring( 0, intStrvalue - Flag );

        }
        for ( int i = 0; i < Flag; i++ ) {
          strvalue = strvalue + "*";
        }

        //System.out.print( "strvalue:" + strvalue );
        return strvalue;
      }
    }
    catch (Exception e) {
      return strvalue;
    }
  }
  

getPassString 功能：用于转换为*。

String strvalue 设置要转换的字符串

int Flag 起位数。

int sFlag 末位数。

public static String getPassString( String strvalue, int Flag, int sFlag ,int iPassLen ) {
  try {
    
    if ( strvalue.equals( "null" ) ) {
      return "";
    } else {
      String strvalue1="";
      String strvalue2="";
      int intStrvalue = strvalue.length();
      if(sFlag>=Flag){
        if ( intStrvalue > Flag ) {
          strvalue1 = strvalue.substring( 0,  Flag );
          strvalue2 = strvalue.substring(  sFlag, intStrvalue );
        } else {
          strvalue1 = "";
          strvalue2 = "";
        }
        for ( int i = 0; i < iPassLen; i++ ) {
          strvalue1 = strvalue1 + "*";
        }
        strvalue=strvalue1+strvalue2;
      }
      //System.out.print( "strvalue:" + strvalue );
      return strvalue;
    }
  }
  catch (Exception e) {
    return strvalue;
  }
  } 

取得字符串iStartPos位置到iEndPos位置，将中间这部分转换iPatternLen个sPattern

EXSAMPLE:

	getPatternString("CHEN ZISHU",5,7,"*",3)
	RESULT: CHEN ***SHU

	getPatternString("CHEN ZISHU",10,0,".",3)
	RESULT: CHEN******

 */
  public static String getPatternString( String s, int iStartPos, int iEndPos, String sPattern, int iPatternLen ) {
    try {
	  if (iEndPos==0) {
		iEndPos = s.length();
	  }
	  
	  String sStartStr = "";
	  String sCenterStr = "";
	  String sEndStr = "";
	  
      if ( s.equals("null")){
        return "";
      } else {
        int ints = s.length();
        if ( ints > iStartPos ) {
          sStartStr = s.substring( 0, iStartPos );
        }else{
          return s;
        }
		if ( ints > iEndPos) {
          sEndStr = s.substring( iEndPos, ints );
		}
        for ( int i = 0; i < iPatternLen; i++ ) {
          sCenterStr = sCenterStr + sPattern;
        }
        return sStartStr + sCenterStr + sEndStr;
      }
    }
    catch (Exception e) {
      System.out.println(e);
      return s;
    }
  }

  public static String getPatternString( String s, int iStartPos, String sPattern, int iPatternLen ) {
    return getPatternString(s,iStartPos,0,sPattern,iPatternLen);
  }

  public static String getPatternString( String s, int iStartPos, String sPattern ) {
    return getPatternString(s,iStartPos,0,sPattern,3);
  }