Java case-sensitive alphanumeric and symbolic

How does Java differentiate between the four kinds of things that title? The first thing I think of is the use of ASCII code, because the different symbols of the ASCII code is not the same. If you want to use ASCII code to differentiate, at least know the ASCII code of a,z,a,z,0,9, so you can use ASCII code to distinguish.

This is the first method.

1  Packagetest;2 ImportJava.util.Scanner;3  Public classdifferentiate{4      Public Static voidMain (string[] args) {5         //a-65,z-90,a-97,z-122,0-48,9-576Scanner sc =NewScanner (system.in);7String nextline =sc.nextline ();8         Char[] Chararray =Nextline.tochararray ();9          for(inti = 0;i<chararray.length;i++){Ten             intCharascii = (int) chararray[i]; One             if(Charascii >=65 && charascii <=90){ ASystem.out.print ("Capital Letter:"); - System.out.println (Chararray[i]); -}Else if(Charascii >=97 && charascii <=122){ theSystem.out.print ("Lowercase letters:"); - System.out.println (Chararray[i]); -}Else if(Charascii >= && charascii <= 57){ -System.out.print ("Number:"); + System.out.println (Chararray[i]); -}Else{ +System.out.print ("Symbol:"); A System.out.println (Chararray[i]); at             } -         } -     } -}

The second method, on-line search data found, seemingly in Java on the a-z,a-z,0-9 char characters are sorted, so you can directly compare.

1  Packagetest;2 3 ImportJava.util.Scanner;4 5  Public classdifferentiate{6      Public Static voidMain (string[] args) {7Scanner sc =NewScanner (system.in);8String nextline =sc.nextline ();9          for(inti = 0; I < nextline.length (); i++) {Ten             Charc =Nextline.charat (i); One             if(c >= ' A ' && C <= ' Z ') { ASystem.out.print ("Max"); - System.out.println (c); -}Else if(c >= ' a ' && c <= ' z ') { theSystem.out.print ("Min"); - System.out.println (c); -}Else if(c >= ' 0 ' && C <= ' 9 ') { -System.out.print ("number"); + System.out.println (c); -}Else { +System.out.print ("symbol"); A System.out.println (c); at             } -         } -     } -}

There is also a way to use the indexof () function, if a character does not exist in the string, it will return-1, so only need to make a-z,a-z,0-9 three strings, and then each time with the three string to determine the line

1  Packagetest;2 3 ImportJava.util.Scanner;4 5  Public classdifferentiate{
6      Public Static voidMain (string[] args) {7Scanner sc =NewScanner (system.in);8String nextline =sc.nextline ();9String upper = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";TenString lower = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; OneString num = "0123456789"; A         Char[] Chararray =Nextline.tochararray (); -          for(inti = 0;i<chararray.length;i++){ -             if(Upper.indexof (chararray[i])! =-1){ theSystem.out.print ("Capital Letter:"); - System.out.println (Chararray[i]); -}Else if(Lower.indexof (chararray[i])! =-1){ -System.out.print ("Lowercase letters:"); + System.out.println (Chararray[i]); -}Else if(Num.indexof (chararray[i])! =-1){ +System.out.print ("Number:"); A System.out.println (Chararray[i]); at}Else{ -System.out.print ("Symbol:"); - System.out.println (Chararray[i]); -             } -         } -     } in}

Java case-sensitive alphanumeric and symbolic