charmethods.java

《A first book of java》by Gary J.Bronson 北大出版社

import java.io.*;
public class CharMethods
{
  public static void main (String[] args) 
  {
    
    String str = new String("This -123/ is 567 A ?<6245> Test!");
    char nextChar;
    int i, numChars;
    int numLetters = 0, numDigits = 0, numOthers = 0;

    System.out.println("The original string is: " + str);
  
    numChars = str.length();
    System.out.println("This string contains " + numChars + " characters,"
                       + " which consists of");    
       // check each character in the string
    for (i = 0; i < numChars; i++)
    {
      nextChar = str.charAt(i);  // get a character
      if (Character.isLetter(nextChar))
        numLetters++;
      else if (Character.isDigit(nextChar))
        numDigits++;
      else
        numOthers++;
    }

    System.out.println("     " + numLetters + " letters");
    System.out.println("     " + numDigits + " digits");
    System.out.println("     " + numOthers + " other characters.");

  }
}