《Java复习题阅读程序题(27页).doc》由会员分享,可在线阅读,更多相关《Java复习题阅读程序题(27页).doc(28页珍藏版)》请在taowenge.com淘文阁网|工程机械CAD图纸|机械工程制图|CAD装配图下载|SolidWorks_CaTia_CAD_UG_PROE_设计图分享下载上搜索。
1、-JAVA程序设计复习题之(三)阅读程序题(通信工程专业使用)三、阅读程序题。1、阅读以下程序:public class Sum public static void main( String args) double sum = 0.0 ; for ( int i = 1; i= 100; i + ) sum += i;, System.out.println( sum= + sum ); 该程序完成的功能是: 求sum=1+2+3+.+100的和。2、阅读以下程序:public class Sum public static void main(String args) double su
2、m = 0.0:for (int i=1; i=100; i+)sum += i*i;System.out.println( sum=+sum); 该程序的功能是: 求出sum的值为1到100的平方和。3、阅读以下程序:public class Sum public static void main(String args) double sum = 0.0;for(int i = 1; i = 100; i+)sum += i*i*i;System.out.println(sum= + sum); 此程序完成的功能是: 计算并输出1到100的立方和sum值。4、阅读以下程序:public c
3、lass Sum public static void main(String args) double sum = 0.0;for (int i=1; i=100; i+) sum += 1.0 / (double)i;System.out.println(sum=+sum); 此程序完成的功能是: 求解sum=1+1/2+1/3+.+1/100的值并打印输出。5、阅读以下程序import java.io.* ;public class Test public static void main(String args ) int i, s = 0;int a = 10, 20, 30, 40
4、, 50, 60, 70, 80, 90;for ( i = 0 ; i a.length; i+ )if(ai % 3 = 0) s += ai;System.out.println(s= + s);请写出此程序的输出结果: s=1806、阅读以下程序 import java.io.*;public class abc public static void main(String args ) AB s = new AB(Great!,I love Eclipse.); System.out.println(s.toString( ); class AB String s1; String
5、s2; public AB(String str1, String str2) s1 = str1; s2 = str2; public String toString( ) return s1 + s2;运行结果是: 运行结果是:Great! I love Eclipse.7、阅读以下程序import java.io.* ; public class abc public static void main(String args ) int i, s = 0 ; int a = 10 , 20 , 30 , 40 , 50 , 60 , 70 , 80 , 90 ; for ( i = 0
6、; i a.length ; i + ) if ( ai%3 = = 0 ) s += ai ; System.out.println(s=+s); 运行结果是: 运行结果:s = 1808、阅读以下程序import java.io.* ; public class abc public static void main(String args ) System.out.println(a= + a + nb= + b); class SubClass extends SuperClass int c; SubClass(int aa, int bb, int cc) super(aa, bb
7、); c = cc; class SubSubClass extends SubClass int a; SubSubClass(int aa, int bb, int cc) super(aa, bb, cc); A = aa + bb + cc; void show( )System.out.println(a=+a+nb=+b+nc=+c); 运行结果是: 运行结果:a=60b=20c=309、以下程序的输出结果为 相等 。class StringTest1 public static void main(String args) String s1=hello;String s2=ne
8、w String(hello);if( s1.equals(s2) ) System.out.println(相等);else System.out.println(不相等);10、以下程序段的输出结果为 5 6 7 8 9 。public class TestArray public static void main(String args ) int i , j ;int a = 5,9,6,8,7; for ( i = 0 ; i a.length-1; i + ) int k = i; for ( j = i ; j a.length; j+ ) if ( aj ak ) k = j;
9、 int temp = ai; ai = ak; ak = temp; for ( i =0 ; ia.length; i+ ) System.out.print(ai+ ); System.out.println( ); 11、写出以下程序的功能。import java.io.*;public class TestFile public static void main(String args) throws Exception BufferedReader br = new BufferedReader(new InputStreamReader(System.in); BufferedW
10、riter bw = new BufferedWriter(new FileWriter(“input.txt); String s; while (true) System.out.print(请输入一个字符串: ); System.out.flush( ); s = br.readLine( ); if (s.length() = 0) break; bw.write(s); bw.newLine(); bw.close( ); 程序功能是: 程序功能是:从键盘逐一输入字符串,逐一输出至input.txt文件中,直至输入空行。12、阅读以下程序,写出输出结果。class Animal An
11、imal( ) System.out.print (Animal ); public class Dog extends Animal Dog( ) System.out.print (Dog ); public static void main(String args) Dog snoppy = new Dog(); 输出结果是: 输出结果是:Animal Dog13、以下程序的输出结果为 Peter is 17 years old! 。public class Person String name;int age;public Person(String name, int age) th
12、is.name = name;this.age = age;public static void main(String args) Person c = new Person(Peter, 17);System.out.println(c.name + is + c.age + years old!);14、以下程序的输出结果为_ 课程号:101 课程名:JSP 学分:3 _。public class Course private String cNumber;private String cName;private int cUnit;public Course(String number
13、, String name, int unit) cNumber = number;cName = name;cUnit = unit;public void printCourseInfo() System.out.println(课程号: + cNumber + 课程名: + cName + 学分: + cUnit);class CourseTest public static void main(String args) Course c;c = new Course(101, JSP, 3);c.printCourseInfo();15、以下程序的输出结果为_ 汤姆猫体重:20.0斤
14、_。public class Tom private float weight;private static String name;public void setWeight(float weight) this.weight = weight;private void out() System.out.println(name + 体重: + weight + 斤);public static void main(String args) Tom.name = 汤姆猫;Tom cat = new Tom();cat.setWeight(20);cat.out();16、以下程序的输出结果是
15、 _姓名:Tom 年龄:15 家庭住址:宿城区 电话:66123456 学校:宿中_。public class Father String name, address, tel;int age;public Father(String name, int age) this.name = name;this.age = age;void out() System.out.print(姓名: + name);System.out.print( 年龄: + age);void outOther() System.out.print( 家庭住址: + address);System.out.prin
16、t( 电话: + tel);class Son extends Father String school;public Son(String name, int age) super(name, age);void out() super.out();super.outOther();System.out.println( 学校: + school);public static void main(String args) Son son = new Son(Tom, 15);son.address = 宿城区;son.school = 宿中;son.tel = 66123456;son.ou
17、t();17、下列程序的运行结果是_ 12345_。public class MyClass int a = 1, 2, 3, 4, 5 ;void out() for (int j = 0; j a.length; j+)System.out.print(aj + );public static void main(String args) MyClass my = new MyClass();my.out();18、阅读下面的程序,回答问题。import java.awt.*; import javax.swing.*; public class T extends JFrame publ
18、ic T ( ) super(GridLayout); Container con=this.getContentPane(); con.setLayout(new GridLayout(2,3); con.add(new JButton(a); con.add(new JButton(b); con.add(new JButton(c); con.add(new JButton(d); con.add(new JButton(e); con.add(new JButton(f); setSize(200, 80); setVisible(true); public static void m
19、ain(String args) new T(); 画图表示程序运行后的图形界面。如果程序通过实现某个接口处理按钮的动作事件,则该接口名为何?接口中的方法头声明如何?答案:接口名:ActionListener 接口中的方法:public void actionPerformed(ActionEvent e)19、阅读下面的程序,并回答问题。import java.io.*;public class Test public static void main(String args) throws IOException BufferedReader buf=new BufferedReader(
20、 new InputStreamReader(System.in); while (true) String str = buf.readLine( ); if( str.equals(quit) ) break; int x = Integer.parseInt(str); System.out.println(x*x); 编译运行上面的程序:从键盘输入5,回车后输出的结果如何?从键盘输入quit,回车后程序执行情况如何?答案:25 终止应用程序的运行。20、阅读下面的程序代码,并回答问题。String s1 = new String(abcde);String s2 = new Strin
21、g(abcde); boolean b1= s1.equals(s2);boolean b2 = s1= s2; System.out.print(b1+ +b2); 程序段执行后,在命令行的输出结果如何?解释输出(1)的结果的原因?答案: true falseequals方法比较两个字符串的内容是否相等;运算符“=”判断两个对象是否指向同一个引用,即是否为同一个对象。21、阅读下面的程序,并回答问题。import java.io.*;public class Test public static void main(String args) throws IOException Buffer
22、edReader buf=new BufferedReader( new InputStreamReader(System.in); while (true) String str = buf.readLine(); if( str.equals(quit) ) break; int x = Integer.parseInt(str); System.out.println(x*x); 编译运行上面的程序:从键盘输入10,回车后输出的结果如何?从键盘输入exit,回车后程序能正确执行吗?为什么?答案:100 不能;因为方法Integer.parseInt(str)不能将字符串“exit”转化为
23、整数,抛出异常。22、写出下面的程序编译、运行后的结果。public class Test public static void main(String args) new Student(Tom, m, 90, 88); new Student(Jack, m, 66, 89); new Student(Mary, f, 76, 86); System.out.println(nametsextchinesetenglish); Student.print(); class Student protected String name; protected char sex; protecte
24、d int chinese; protected int english; protected Student next; static Student list; Student (String name, char sex, int chinese, int english) this.name=name; this.sex=sex; this.chinese=chinese; this.english=english; this.next=list; list=this; static void print() Student friend=list; if (friend=null)
25、System.out.println(The list is empty.); else do System.out.println(friend.toString(); friend=friend.next; while(friend!=null); public String toString() return new String(name+t+sex+t+chinese+t+english); 答案:name sex chinese englishMary f 76 86Jack m 66 89Tom m 90 8823、阅读下列程序:public class Sumpublic st
26、atic void main(String args)int j=10;System.out.println(j is : +j);calculate(j);System.out.println(At last, j is : +j);static void calculate (int j)for (int i = 0;i= 0) if (x 0)y = 1; else y = 0; else y = -1; System.out.println(y); 程序的输出结果是:_答案:130、 阅读程序,写出正确的运行结果。 public class Father int a = 100; public void miner( ) a-; public static void main(String args