【单选题】给出以下代码: class C1 {} class C2 extends C1 { } class C3 extends C2 { } class C4 extends C1 {} C1 c1 = new C1(); C2 c2 = new C2(); C3 c3 = new C3(); C4 c4 = new C4(); 以下哪个表达式的计算结果为false?
【单选题】给定以下代码class C1 {}class C2 extends C1 { }class C3 extends C2 { }class C4 extends C1 {}C1 c1 = new C1();C2 c2 = new C2();C3 c3 = new C3();C4 c4 = new C4();下列哪个表达式的结果为false?
【单选题】The policemen went into action______when they heard the alarm.
【单选题】BOT项目包括的具体形式中,BOO形式的含义是()。
【单选题】假设c1、c2和c3是3个命令。以下哪个命令表示c1执行成功才执行c2,c1执行出错则不执行c2。不论c1出错与否,后面都会执行c3?
【单选题】A compute is a ( ) and programmable electronic processing machine.
【单选题】The policemen went into action ______ they heard the alarm.
【单选题】给定以下类和它们的对象:class C1 {};class C2 extends C1 {};class C3 extends C1 {};C2 c2 = new C2();C3 c3 = new C3();分析以下赋值语句c2 = (C2)((C1)c3);
B.
得到一个错误,因为不能从兄弟类进行 对象 显示转换。
C.
得到一个错误,因为java无法 嵌套 执行多个 对象 显示 转换