思迁数码科技Java软件工程师笔试题和面试题答案(二)

　　C.the code will not compile.

　　D.None of these.

　　7:

　　What is the result when you compile and run the following code?

　　public class ThrowsDemo

　　{

　　static void throwMethod()

　　{

　　System.out.println("Inside throwMethod.");

　　throw new IllegalAccessException("demo");

　　}

　　public static void main(String args[])

　　{

　　try

　　{

　　throwMethod();

　　}

　　catch (IllegalAccessException e)

　　{

　　System.out.println("Caught " + e);

　　}

　　}

　　}

　　Choices:

　　What is the result when you compile and run the following code?

　　public class ThrowsDemo

　　{

　　static void throwMethod()

　　{

　　System.out.println("Inside throwMethod.");

　　throw new IllegalAccessException("demo");

　　}

　　public static void main(String args[])

　　{

　　try

　　{

　　throwMethod();

　　}

　　catch (IllegalAccessException e)

　　{

　　System.out.println("Caught " + e);

　　}

　　}

　　}

　　Choices:

　　A.Compilation error

　　B.Runtime error

　　C.Compile successfully, nothing is printed.

　　D.Inside throwMethod. followed by caught:java.lang.IllegalAccessExcption: demo

　　8:假定a和b为int型变量,则执行下述语句组后,b的值为

　　a=1;

　　b=10;

　　do

　　{

　　b-=a;

　　a++;

　　} while (b--<0);

　　A.9

　　B.-2

　　C.-1

　　D.8

　　9:

　　public class X{

　　public Object m(){

　　Object o = new Float(3.14F);//line 3

　　Object [] oa = new Object;//line 4

　　oa[0] = o;//line 5

　　o=null;//line 6

　　return oa[0];//line 7

　　}

　　}

　　When is the Float object, created in line 3,eligible for garbage collection?

　　public class X{

　　public Object m(){

　　Object o = new Float(3.14F);//line 3

　　Object [] oa = new Object;//line 4

　　oa[0] = o;//line 5

　　o=null;//line 6

　　return oa[0];//line 7

　　}

　　}

　　When is the Float object, created in line 3,eligible for garbage collection?

　　A.just after line 5.

　　B.just after line 6

　　C.just after line 7(that is,as the method returns)

　　D.never in this method

　　10:Math.round(-11.5)等於多少?

　　A.-11

　　B.-12

　　C.-11.5

　　D.none

　　11:In the following pieces of code, which one will compile without any error?

　　A.StringBuffer sb1 = "abcd";

　　B.Boolean b = new Boolean("abcd");

　　C.C: byte b = 255;

　　D.float fl = 1.2;

　　12:

　　Give the following method:

　　public void method( ){

　　String a,b;

　　a=new String(“hello world”);

　　b=new String(“game over”);

　　System.out.println(a+b+”ok”);

　　a=null;

　　a=b;

　　System.out.println(a);

　　}

　　In the absence of compiler optimization, which is the earliest point the object a refered is definitely elibile to be garbage collection.

　　Give the following method:

　　public void method( ){

　　String a,b;

　　a=new String(“hello world”);

　　b=new String(“game over”);

　　System.out.println(a+b+”ok”);

　　a=null;

　　a=b;

　　System.out.println(a);

　　}

　　In the absence of compiler optimization, which is the earliest point the object a refered is definitely elibile to be garbage collection.

　　A.before line 5

　　B.before line 6

　　C.before line 7

　　D.before line 9

　　13:

　　Give the following java class:

　　public class Example{

　　static int x[]=new int[15];

　　public static void main(String args[]){

　　System.out.println(x[5]);

　　}

　　}

　　Which statement is corrected?

　　Give the following java class:

　　public class Example{

　　static int x[]=new int[15];

　　public static void main(String args[]){

　　System.out.println(x[5]);

　　}

　　}

　　Which statement is corrected?

　　A.When compile, some error will occur.