JAVA基础-“String” 关键字

package Dom1.com

public class Dom{

public static void main (String[] args) {

String name = "你好啊";

String str1 = "你好" + name + "世界";

System.out.println (str1);

String str2 = "JAVA world";

System.out.println (str2.replace("JA","ja"));

String str3 = "每日坚持练习";

System.out.println (str3.substring(0,2));

}

}