判断字符串是否由数字和字母构成

    public static boolean normalstr(String s){
       	int len = s.length();
       	for(int i=0;i<len;i++) {
       		char ch = s.charAt(i);
       		if(!Character.isLetterOrDigit(ch)) {
       			return false;
       		}
       	}
       	return true;
    }
    public static void main(String[] args) {
    	String s1 = "a123b";
    	String s2 = "..123sdf";
    	System.out.println("s1:"+normalstr(s1));
    	System.out.println("s2:"+normalstr(s2));
    }
    
    
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
    
    AI写代码

    public static boolean digitorlettler(char ch) {
    	if((ch>='A'&&ch<='Z')||(ch>='a'&&ch<='z')||(ch>='0'&&ch<='9')) {
    		return true;
    	}
    	return false;
    }
    public static boolean mynormalstr(String s){
       	int len = s.length();
       	for(int i=0;i<len;i++) {
       		char ch = s.charAt(i);
       		if(!digitorlettler(ch)) {
       			return false;
       		}
       	}
       	return true;
    }
    
    
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
    
    AI写代码

    public static boolean isLetterOrDigit(int codePoint) {
        return ((((1 << Character.UPPERCASE_LETTER) |
            (1 << Character.LOWERCASE_LETTER) |
            (1 << Character.TITLECASE_LETTER) |
            (1 << Character.MODIFIER_LETTER) |
            (1 << Character.OTHER_LETTER) |
            (1 << Character.DECIMAL_DIGIT_NUMBER)) >> getType(codePoint)) & 1)
            != 0;
    }
    
    
      
      
      
      
      
      
      
      
      
    
    AI写代码