博彦科技(北京)有限公司武汉分公司Java高级软件工程师.doc

选择题 1:关于垃圾收集的哪些叙述是对的。 A.程序开发者必须自己创建一个线程进行内存释放的工作。 B.垃圾收集将检查并释放不再使用的内存。 C.垃圾收集允许程序开发者明确指定并立即释放该内存。 D.垃圾收集能够在期望的时间释放被java对象使用的内存。 2: Select?valid?identifier?of?Java:?? Select valid identifier of Java: A.%passwd B.3d_game C.$charge D.this 3: What?will?be?the?result?of?executing?the?following?code?? ?? ?? public?static?void?main(String?args[]) ?? { ?? ???char?digit?=?a; ?? ???for?(int?i?=?0;?i??10;?i++) ?? ???{ ?? ?????switch?(digit) ?? ?????{ ?? ???????case?x?: ?? ???????{ ?? ?????????int?j?=?0; ?? ?????????System.out.println(j); ?? ???????} ?? ???????default?: ?? ???????{ ?? ???????int?j?=?100; ?? System.out.println(j); ?? ???????} ?? ?????} ?? ??} ?? ??int?i?=?j; ?? ??System.out.println(i); ?? }? ?? ?? Choices:?? What will be the result of executing the following code? public static void main(String args[]) { char digit = a; for (int i = 0; i 10; i++) { switch (digit) { case x : { int j = 0; System.out.println(j); } default : { int j = 100; System.out.println(j); } } } int i = j; System.out.println(i); } Choices: A.100 will be printed 11 times. B.The code will not compile because the variable i cannot be declared twice within the main() method. C.The code will not compile because the variable j cannot be declared twice within the switch statement. D.None of these. 4:A class design requires that a member variable should be accessible only by same package, which modifer word should be used? A.protected B.public C.no modifer D.private 5:以下的C程序代码片段运行后C和d的值分别是多少 Int a =1,b =2; Int c,d; c =(ab)a; d =(ab)a; A.0,0 B.0,1 C.1,0 D.1,1 6: What?will?happen?when?you?attempt?to?compile?and?run?the?following?code?? ?? ?? class?Base? ?? ?? { ?? ?? int?i?=?99;? ?? ?? public?void?amethod() ?? ?? { ?? ?? ???????System.out.println(Base.amethod()); ?? ?? ?????} ?? ?? ?????Base() ?? ?? { ?? ?? ?????amethod(); ?? ?? ?????} ?? ?? }? ?? ?? public?class?Derived?ext