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1>ÓÃJAVA×Ô´øµÄº¯Êý
public static boolean isNumeric(String str){
  for (int i = str.length();--i>=0;){  
   if (!Character.isDigit(str.charAt(i))){
    return false;
   }
  }
  return true;
}
2>ÓÃÕýÔò±í´ïʽ
public static boolean isNumeric(String str){
    Pattern pattern = Pattern.compile("[0-9]*");
    return pattern.matcher(str).matches();  
}
3>ÓÃasciiÂë
public static boolean isNumeric(String str){
   for(int i=str.length();--i>=0;){
      int chr=str.charAt(i);
      if(chr<48 || chr>57)
         return false;
   }
   return true;
}
4>ÓÃÒì³£
public static boolean isNumeric(String str){
try{
Integer.parseInt(str);
}
catch(NumberFormatException ne){
return false;
}
return true;
}


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import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
public class TestStr {
public static void main(String[] args) {
   getDates();
}
public static void getDates() ......

java thisºÍsuper¹Ø¼ü×Ö ÓÐʲô×÷ÓÃ

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     Ò»Ö±ÏëʵÏÖÏñDriverManagerÄÇÑùµÄgetConnection·½·¨£¬Í¨¹ý´Ë·½·¨¾Í¿ÉÒÔ»ñµÃÁ¬½Ó£¬¶øÇÒ»¹²»ÓÃÖ¸¶¨Driver£¬µ«Ç°ÌáÊÇDriverÒѾ­Í¨¹ýClass.forName()»ònew Driver()½øÐÐÁ˼ÓÔØ¡£½ñÌìÖÕÓÚµÃÒÔʵÏÖ¡£
      package quiz;
import java.lang.reflect.Field;
public class Cl ......
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