System.out.println("a等于b：" + (a==b));中為什么要有+
public class HelloWorld{
??? public static void main(String[] args) {
??int a=16;
??double b=9.5;
??String str1="hello";
??String str2="imooc";
??System.out.println("a等于b：" + (a==b));
??System.out.println("a大于b：" + (a>=b));
??System.out.println("a小于等于b：" + (a<=b));
??System.out.println("str1等于str2：" + (str1?? ==str2));
?}
}
2019-12-03
這是字符串連接符，String c = "xxxx" + "xcccccc";