java基础之字符串字母大小写转换、倒序

/**
 *  字符串字母大小写转换、并倒序输出
 *  zzl
 */


public class Shuffle {

	public static void main(String[] args) {

       String str = "SDdfsDdSwqrewASDASD";

       //字符串转成char数组
       char [] ch = str.toCharArray();

       StringBuffer buffer = new StringBuffer();

       for(int i=str.length()-1;i>=0;i--){
    	   if(ch[i]>='A'&&ch[i]<='Z'){
    		   buffer.append(String.valueOf(ch[i]).toLowerCase());
    	   }else if(ch[i]>='a'&&ch[i]<='z'){
    		   buffer.append(String.valueOf(ch[i]).toUpperCase());
    	   }
       }
       System.out.println(buffer.toString());

	}


}