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());

	}
	
	
}