JAVA期末考试模拟试题

一、选择题(每小题1分，共10 分，注：选择答案可能不止一个正确)1、编译Java Application 源程序文件将产生相应的字节码文件，这些字节码文件的扩展名为( )。

A. .javaB. .classC. .htmlD. .exe2、设x = 1 , y = 2 , z = 3，则表达式y＋＝z－－/＋＋x 的值是( )。

A. 3B. 3. 5C. 4D. 53、在Java Applet程序用户自定义的Applet子类中，一般需要重载父类的( )方法来完成一些画图操作。

A. start( ) B. stop( ) C. init( ) D. paint( )4、不允许作为类及类成员的访问控制符的是( )。

A. publicB. privateC. staticD. protected5、为AB类的一个无形式参数无返回值的方法method书写方法头，使得使用类名AB作为前缀就可以调用它，该方法头的形式为( )。

A. static void method( )B. public void method( )C. final void method( )D. abstract void method( )6、下面哪些是java语言中的关键字？ A. sizeof B. abstract C. NULL D. Native7、下面语句哪个是正确的？A. char c ='abc';B. long l=oxfff;C. float f=0.23;D. double d =0.7E-3;8、以下程序测试String 类的各种构造方法，试选出其运行效果。

class STR{public static void main(String args[]){String s1=new String();String s2=new String("String 2");char chars[]={'a',' ','s','t','r','i','n','g'};String s3=new String(chars);String s4=new String(chars,2,5);byte[] bytes={72,101,108,108,79,33}; //A、a和“!”号的ASCII分别为65、97和33StringBuffer sb=new StringBuffer(s3);sb.append(“!”);String s5=new String(sb);String s6 = new String(bytes);System.out.println("The String No.1 is "+s1);System.out.println("The String No.2 is "+s2);System.out.println("The String No.3 is "+s3);System.out.println("The String No.4 is "+s4);System.out.println("The String No.5 is "+s5);System.out.println("The String No.6 is "+s6);}}A . The String No.1 is B. The String No.1 isThe String No.2 is String The String No.2 is String 2The String No.3 is a string The String No.3 is a stringThe String No.4 is string The String No.4 is strinThe String No.5 is a string The String No.5 is a string!The String No.6 is HELLO! The String No.6 is Hello!C. The String No.1 isThe String No.2 is String 2The String No.3 is a string D 以上都不对The String No.4 is strinThe String No.5 is a stringThe String No.6 is hello!9、下面语句段的输出结果是（）int i = 9;switch (i) { default: System.out.println("default");case 0: System.out.println("zero"); break;case 1: System.out.println("one");case 2: System.out.println("two"); }A. defaultB. default, zeroC. error default clause not definedD. no output displayed10、下面哪些语句能够正确地生成5个空字符串？A . String a[]=new String[5]; B. String a[]={"","","","",""};for(int i=0;i<5;a[++]=""); D. String[5] a; C. String a[5]; E. String[] a=new String[5]; 11、下面哪些选项将是下述程序的输出？public class Outer{public static void main(String args[]){for(int i=0; i<3; i++) for(int j=0;j<3;j++){ if(j>1) break; System.out.println(j+"and"+i);} }}A. 0 and 0B. 0 and 1C. 0 and 2D. 0 and 3E. 2 and 2F. 2 and 1G. 2 and 012、在编写Java Application程序时，若需要使用到文件输入输出语句，必须在程序的开头写上( )语句。

A、import java.awt.* ;B、import java.applet.Applet ;C、import java.io.* ;D、import java.awt.Graphics ;13. 下列可作为正确的java标识符使用的是：A、MyClass, $amount, _totalGradesB、$美元, instanceOf, TAX_RATEC、one, My Class, numberOf*sD、final, 1Way, new14、下列程序的运行结果为：（A的ASCII为65, 1的ASCII为49, a的ASCII为97）char c1='A', c2='1'; System.out.println(c1+3); //68System.out.println((char)(c1+3)); //D System.out.println((char)(c1+c2)); //rA. D D rB. 68 D wC. D D rD. 68 D r15、下列程序的运行结果为：System.out.println(37D); //37.0 System.out.println(037); //31System.out.println(037D); //37.0 System.out.println(0x37D); //893A. 37.0 37 37 37B. 37.0 31 37.0 37.0C. 37.0 31 37.0 893D. 37.0 37 31 89316、下列程序的运行结果为：Integer n1 = new Integer(47); Integer n2 = new Integer(47);System.out.println(n1 = = n2); //false System.out.println(n1.equals(n2)); //truen1 = n2; System.out.println(n1 ! = n2); //false System.out.println(n1.equals(n2)); //trueA. true true true trueB. false false false trueC. false true false trueD. true true false true17、下列程序中出错的语句为：class A { void f(int x,int y){}static void g(int a, int b){}public static void main(String[] args){A a1 = new A();a1.f(2,3); (1)a1.g(2,5);(2)A.f(4,6); // error (3)A.g(8,9); (4)f(4,6); // error (5)g(8,9); } } (6)A. (2) (4) (6)B. (1) (3) (5)C. (3) (5)D. (4) (6)18、下列说法正确的是：public class TestFinal {Random rnd = new Random();final int a = rnd.nextInt();final static double pi = 3.1415926;final Person teacher = new Person("kongzi"); // Person(Sting name)为Person类的构造器static void f(final int i){System.out.println(i+=100);}public static void main(String[] args) {TestFinal test1 = new TestFinal();TestFinal test2 = new TestFinal();}}A、test1.a 与test2.a 的值相同；test1.pi 与test2.pi 的值相同；test1与test2的teacher属性是同一个Person类型对象；方法f()存在错误，应将f(final int i)改为f(int i)B、test1.a 与test2.a的值可能相同，也可能不同；test1.pi 与test2.pi 的值相同；test1与test2的teacher属性是不同的Person类型对象；方法f()存在错误，应将i+=100改为i+100C、test1.a 与test2.a的值一定不同；test1.pi 与test2.pi 的值相同；test1与test2的teacher属性是不同的Person类型对象；方法f()存在错误，应将f(final int i)改为f(int i)D、test1.a 与test2.a的值不同；test1.pi 与test2.pi 的值不同；test1与test2的teacher属性是同一个Person类型对象；方法f()存在错误，应将f(final int i)改为f(int i)19. 下列哪些程序段是正确的？B、E、FA. class IceCream {B.class IceCream {private void sd(String s){ void sd(String s){System.out.println(s); } System.out.println(s); }public IceCream(){ public IceCream(){sd(“I am a IceCream!”); } } sd(“I am a IceCream!”); }}public Class Sundae extends IceCream{ public Class Sundae extends IceCream{ public static void main(){ public static void main(){Sundae x = new Sundae(); Sundae x = new Sundae();IceCream y = new IceCream(); IceCream y = new IceCream();y.sd(“It is a Sundae!”); y.sd(“It is a Sundae!”);x.sd(“I am in Sundae class”); } } x.sd(“I am in Sundae class”); }}C. Dpackage edu.zjut package edu.zjutpublic class IceCream { public class IceCream {void sd(String s){ protected void sd(String s){System.out.println(s); } System.out.println(s); }public IceCream(){ public IceCream(){sd(“I am a IceCream!”); } } ……sd(“I am a IceCream!”); } }……. package com.w3c package com.w3Cpublic Class Sundae extends IceCream{ public Class Sundae extends IceCream{ public static void main(){ public static void main(){Sundae x = new Sundae(); Sundae x = new Sundae();IceCream y = new IceCream(); IceCream y = new IceCream();y.sd(“It is a Sundae!”); y.sd(“It is a Sundae!”);x.sd(“I am in Sundae class”); } } x.sd(“I am in Sundae class”); } }E. Fpackage edu.zjut package edu.zjutpublic class IceCream { public class IceCream {public void sd(String s){ protected void sd(String s){System.out.println(s); } System.out.println(s); }public IceCream(){ public IceCream(){sd(“I am a IceCream!”);} } ……sd(“I am a IceCream!”); } }……. package com.w3c package edu.zjutpublic Class Sundae extends IceCream{ public Class Sundae extends IceCream{ public static void main(){ public static void main(){Sundae x = new Sundae(); Sundae x = new Sundae();IceCream y = new IceCream(); x.sd(“I am in Sundae class”); }}y.sd(“It is a Sundae!”);x.sd(“I am in Sundae class”); }}二、填空题（每空格1分，共20 分）1、开发与运行Java程序需要经过的三个主要步骤为、和。