Java工程师笔试题和面试题答案(二)

　　A.计划阶段、开发阶段、运行阶段

　　B.设计阶段、开发阶段、编码阶段

　　C.设计阶段、编码阶段、维护阶段

　　D.计划阶段、编码阶段、测试阶段

　　9:

　　What happens when you try to compile and run the following program?

　　class Mystery{

　　String s;

　　public static void main(String[] args){

　　Mystery m=new Mystery();

　　m.go();

　　}

　　void Mystery(){

　　s=”constructor”;

　　}

　　void go(){

　　System.out.println(s);

　　}

　　}

　　What happens when you try to compile and run the following program?

　　class Mystery{

　　String s;

　　public static void main(String[] args){

　　Mystery m=new Mystery();

　　m.go();

　　}

　　void Mystery(){

　　s=”constructor”;

　　}

　　void go(){

　　System.out.println(s);

　　}

　　}

　　A.this code compliles but throws an exception at runtime

　　B.this code runs but nothing appears in the standard output

　　C.this code runs and “constructor” in the standard output

　　D.this code runs and writes ”null” in the standard output

　　10:

　　Give the following java class:

　　public class Example{

　　public static void main(String args[]){

　　static int x[] = new int[15];

　　System.out.println(x[5]);

　　}

　　}

　　Which statement is corrected?

　　Give the following java class:

　　public class Example{

　　public static void main(String args[]){

　　static int x[] = new int[15];

　　System.out.println(x[5]);

　　}

　　}

　　Which statement is corrected?

　　A.When compile, some error will occur.

　　B.When run, some error will occur.

　　C.Output is zero.

　　D.Output is null.

　　11:

　　public class X{

　　public Object m(){

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

　　Object [] oa = new Object[1];//line 4

　　oa[0] = o;//line 5

　　o=null;//line 6

　　return oa[0];//line 7

　　}

　　}