java string 字母小写 java string转小写

import static jdk.nashorn.internal.objects.NativeString.toLowerCase;
import static jdk.nashorn.internal.objects.NativeString.toUpperCase;

/**
 * 该代码展示字符串大小写
 */

public class test {
    public static void main(String[] args) {
    	//方法一:
        System.out.println("简单测试一下");
        String a = "abcdef";
        String b = toLowerCase(a);
        String c = toUpperCase(a);
        System.out.println("换为大写后是:"+b);
        System.out.println("转换为小写后是:" + c);
        System.out.println("---------------分割------------");

		//方法二:
        String aa ="abcdef";
        String bb = aa.toUpperCase();
        System.out.println(bb);
        String cc = bb.toLowerCase();
        System.out.println(cc);
    }

}