摘要:
1,springboot升级版本以后websocket连接出现以下错误 java.lang.IllegalArgumentException: When allowCredentials is true, allowedOrigins cannot contain the special value 阅读全文
摘要:
1,a+=b相当于a=a+b,也相当于a=b+a吗? 例: String a = "1"; String b = "2"; a = a+b;//"12" a = b+a;//"21" 2,下列代码有错吗? byte a = 2; int b = 3; a += b; a = a + b; 第四行有错 阅读全文
摘要:
1, int x = 7; int y = 3; int t; t=x; x=y; y=t; 2, int x = 7; int y = 3; x = x + y; y = x - y; x = x - y; 3, int x = 7; //0111 int y = 3; //0011 x = x^ 阅读全文