一些非常有用的JAVA常用方法(1)

  作者:xiaoyou
出处: www.csdn.com  

  





<％!
stc_RSYB_Name stcRSYName1[];
stc_SYB_INF stcSYBINF1[];
％>

<％/*
   String p = (String) session.getValue("access");
   if (p==null !p.equals("1")) {
     response.sendRedirect("error.htm");
     return;
   }*/
％>
<％!
file://得到机器名字或IP
String get_Myhostname(javax.servlet.http.HttpServletRequest request){
  String myhostname = null;
    try{
      myhostname = request.getRemoteHost();
      myhostname = myhostname.toUpperCase();
    }catch(Exception e){}
  return myhostname;
}
file://处理空字符串
  String dealNull(String str) {
    String returnstr = null;
    if (str == null) returnstr = "";
    else returnstr = str;
    return returnstr;
  }
file://处理空对象  
  Object dealNull(Object obj){
    Object returnstr = null;
    if (obj == null) returnstr = (Object)("");
    else returnstr = obj;
    return returnstr;
  }

  int dealEmpty(String s) {
    s = dealNull(s);
    if (s.equals("")) return 0;
    return Integer.parseInt(s);
  }

String replace(String str,String substr,String restr){
  String[] tmp = split(str,substr);
  String returnstr = null;
  if(tmp.length!=0) {
    returnstr = tmp[0];
    for(int i = 0 ; i < tmp.length - 1 ; i++)
      returnstr =dealNull(returnstr) + restr +tmp[i+1];
  }
  return dealNull(returnstr);
}   
   
String htmlEncode(String txt){
  txt = replace(txt,"&","&");
  txt = replace(txt,"&","&");
  txt = replace(txt,""",""");
  txt = replace(txt,"\"",""");
  txt = replace(txt,"<","<");
  txt = replace(txt,"<","<");
  txt = replace(txt,">",">");
  txt = replace(txt,">",">");
  txt = replace(txt," "," ");
  txt = replace(txt," "," ");
  return txt;
}

String unHtmlEncode(String txt){
  txt = replace(txt,"&","&");
  txt = replace(txt,""","\"");
  txt = replace(txt,"<","<");
  txt = replace(txt,">",">");
  txt = replace(txt," "," ");
  return txt;
}

file://ALERT Function
  void sAlert(String title,String msg,String focus, JspWriter out){
   try {
      out.println("<script language='javascript'>");
      out.println("alert(\"" + title + "\" + \"\\r\\n\" + \"" + replace(replace(msg,"''","'"),"\"","\\\"") +"\");");
      out.println(focus);
      out.println("</script>");
   } catch(Exception e) { System.out.println(e);}
  }
file://CONFIRM Function
  void sConfirm(String title,String msg ,String location,JspWriter out){
    try{
        out.println("<script language='javascript'>");
  out.println("if(confirm(\"" + title + "\" + \"\\r\\n\" + \"" + replace(msg,"\"","\\\"") + "\")){" );
        out.println("var d = (new Date()).toString();");
  out.println(location + "+ d;");
        out.println("}");
        out.println("parent.document.form1.text1.select();");
        out.println("</script>");
   } catch (Exception e) { }
  }
  
file://得到字符串长度  
  int getStringLength(String s) {
   int p = 0;
    try {
      int iLength = 0;
      int irealLength = 0;
      int j = 0;
      p = s.getBytes("Shift_JIS").length;
    } catch(java.io.UnsupportedEncodingException e) {}
    return p;
  }

void formatString(String s,int b,JspWriter out){
    b--;
    String t = "";
    try {
        int leng = getStringLength(s);
        int j = 0;
if (leng > b) {
   for (int i = 1; i <= b ; i++) {
            t = s.substring(0,i);
     if (t.getBytes("Shift_JIS").length <= b ) {
       j++;
     } else break;
   }
          file://j = j+1;
          file://System.out.println("b=" + b + "----" + "j=" + j);
          for(int i = 0;i < j; i++){
            if(s.substring(i,i+1).equals(" "))
              out.print(" ");
            if(!s.substring(i,i+1).equals(" "))
       out.print(htmlEncode(s.substring(i,i+1)));
           }    
          if (s.substring(0,j).getBytes("Shift_JIS").length  == b){
            out.print("");
          }else{
            out.print(" ");
          }
        } else {
   for (int  i = 0; i < b - leng ; i++)
            t = t + " ";
          for (int i = 0; i < s.length(); i++){
            if(s.substring(i,i+1).equals(" "))
              out.print(" ");
            if(!s.substring(i,i+1).equals(" "))
              out.print(htmlEncode(s.substring(i,i+1)));
          }
   out.print(htmlEncode(t + ""));
       }
    } catch(Exception e){System.out.println("----" + e);}
  }

file://判断是否为数字
boolean isNumeric(String number)
{
try
{
  Integer.parseInt(number);
  return true;
}
catch(NumberFormatException sqo)
{
  return false;
}
}
file://判断是否为日期
String mk_date(String c_date,int c_mode)
{
String wk_buf= "";
String ToDay = "";
try
{
  ToDay = Integer.toString(java.util.Calendar.getInstance().get(java.util.Calendar.YEAR));
  switch(c_mode)
  {
   case 0:
   {
    wk_buf = c_date.substring(2, 4) + "/" + c_date.substring(4, 6);
             if (c_date.length() == 8)
    {
                 wk_buf = wk_buf + "/" + c_date.substring(6, 8);
             }
    break;
   }
   case 1:
   {
    for (int i=0; i<c_date.length();i++)
    {
              if (c_date.substring(i, i+1) == " ")
     {
                     wk_buf = wk_buf + "0";
                 }
     else
     {
                     wk_buf = wk_buf + c_date.substring(i, i+1);
                 }
    }
             c_date = wk_buf;
    wk_buf = "";
             if (c_date.substring(0, 1) != "0" )
    {
                 wk_buf = "19";
             }
    else
    {
                 wk_buf = "20";
             }
    
             wk_buf = wk_buf + c_date.substring(0, 2) + c_date.substring(3, 5);
    
             if (c_date.length() == 8)
    {
                  wk_buf = wk_buf + c_date.substring(6, 8);
             }
    break;
   }
   case 2:
   {
    wk_buf = c_date.substring(0, 4) + c_date.substring(5, 7) + c_date.substring(8, 10);
    break;
   }
   case 3:
   {
    for(int i=0; i<c_date.length();i++ )
    {
                 if (c_date.substring(i, i+1) == " ")
     {
                     wk_buf = wk_buf + "0";
                 }
     else
     {
                     wk_buf = wk_buf + c_date.substring(i, i+1);
                 }
             }
             c_date = wk_buf;
             wk_buf = "";
             if (Integer.parseInt(c_date.substring(0,2)) > Integer.parseInt(ToDay.substring(2, 4)))
    {
                 wk_buf = Integer.toString(Integer.parseInt(ToDay.substring(0,2)) - 1);
             }
    else
    {
                 wk_buf = ToDay.substring(0,2);
             }
             wk_buf = wk_buf + c_date.substring(0,2) + c_date.substring(3,5);
             if (c_date.length() == 8)
    {
                 wk_buf = wk_buf + c_date.substring(6,8);
              }
    break;
   }
   case 4:
   {
    wk_buf = c_date.substring(0,4) + "/" + c_date.substring(4,6) + "/" + c_date.substring(6, 8);
    break;
   }
   case 5:
   {
    wk_buf = c_date.substring(0,4) + c_date.substring(5, 7);
    break;
   }
  }
}
catch(Exception e)
{
  System.out.println("wrong : " + e);
}
return wk_buf;
}