Character类
java.lang.Character
父类:java.lang.Object
1.Character构造方法
public Character(char value)
eg: Character c = new Character('a')
2.Character类部分方法
1>public static boolean isDigit(char ch)
1>public static boolean isUpperCase(char ch)
1>public static boolean isLowerCase(char ch)
1>public static char toUpperCase(char ch)
1>public static char toLowerCase(char ch)
public class CharacterDemo { public static void main(String[] args) { Character leo9257 =new Character('@'); char guiyang = leo9257.charValue(); Character.isDigit('0'); Character.isUpperCase('A'); Character.isLowerCase('a'); //判断一下一个字符串中各种字符的个数: //String s = "nanjing.guiyang@2009"; /*int u_count=0; int l_count=0; int d_count=0; int o_count=0; //第一种方式:charAt(); for (int i = 0; i < s.length(); i++) { char ch = s.charAt(i); if(Character.isUpperCase(ch)){ u_count++; }else if(Character.isLowerCase(ch)){ l_count++; }else if(Character.isDigit(ch)){ d_count++; }else{ o_count++; } } */ //第二种方式:toCharArray(); String s = "nanjing.guiyang@2009"; int u_count=0; int l_count=0; int d_count=0; int o_count=0; char[] chs= s.toCharArray(); for (int i = 0; i < chs.length; i++) { if(Character.isUpperCase(chs[i])){ u_count++; }else if(Character.isLowerCase(chs[i])){ l_count++; }else if(Character.isDigit(chs[i])){ d_count++; }else{ o_count++; } } } }