大学期末考试 Java题库.docx

1、大学期末考试 Java题库1.下面程序的运行结果是（ ）。public class E3 public static void main(String args) String s=大大; char a=s.charAt(2),b=s.charAt(4); System.out.print(a); System.out.println(b); 2.下面程序的运行结果是（ ）。import java.util.*;public class LinkedListExample public static void main(String args) LinkedList linkedlist =

2、new LinkedList(); linkedlist.add(new Integer(1); linkedlist.add(new Integer(2); linkedlist.add(new Integer(3); linkedlist.add(new Integer(4); linkedlist.add(new Integer(5); System.out.println(The original contents of the linkedlist is: ); System.out.println(linkedlist); linkedlist.add(2,hello); link

3、edlist.addFirst(First); linkedlist.addLast(Last); System.out.println(After adding elements，the linkedlist is: ); System.out.println(linkedlist); 答：3.下面程序的运行结果是（ ）。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; fo

4、r (j = i; j a.length; j+) if (aj ak) k = j; int temp = ai; ai = ak; ak = temp; for (i = 0; i a.length; i+) System.out.print(ai + ); System.out.println(); 4.下面程序的运行结果是（ ）。public class TryCatchFinally static void Proc(int sel) try if (sel = 0) System.out.println(no Exception ); return; else if (sel =

5、1) int i = 0; int j = 4 / i; catch (ArithmeticException e) System.out.println(Catch ); catch (Exception e) System.out.println(Will not be executed); finally System.out.println(finally); public static void main(String args) Proc(0); Proc(1); 5.下面程序的运行结果是（ ）。public class welcomeTest public static void

6、 main(String args) String s, s1 = ; char c; s = wELCOME; for (int i = 0; i = a & c = z) s1 = s1 + Character.toUpperCase(c); else s1 = s1 + Character.toLowerCase(c); System.out.println(s1); 6.下面程序的运行结果是（ ）。public class arrTest public static void main(String args) int i, j; int a = 2, 1, 4, 8; for (i

7、= 0; i a.length - 1; i+) int k = i; for (j = i; j a.length; j+) if (aj ak) k = j; int temp = ai; ai = ak; ak = temp; for (i = 0; i a.length; i+) System.out.print(ai + ); System.out.println(); 7.下面程序的运行结果是（ true,false）。public class StringTest public static void main(String args) String s1 = new Strin

8、g(abcde); String s2 = new String(abcde); boolean b1 = s1.equals(s2); boolean b2 = s1 = s2; System.out.print(b1 + , + b2); 8.下面程序运行时，若输入10，则输出结果是（ ）。public class test public static void main(String args) throws IOException BufferedReader buf = new BufferedReader( new InputStreamReader(System.in); whi

9、le (true) String str = buf.readLine(); if (str.equals(quit) break; int x = Integer.parseInt(str); System.out.println(x * x); System.out.println(“OK”); 9.下面程序的运行结果是（ ）。public class T public static void main(String args) Set set = new HashSet(); set.add(new Integer(10); set.add(new Integer(5); set.add

10、(new Integer(15); set.add(new Integer(5); set.add(new Integer(10); System.out.println(size = + set.size(); Iterator it = set.iterator(); while (it.hasNext() System.out.print(it.next() + ); 10.下面程序的运行结果是（ ）。public class A class Dog private String name; private int age; public int step; Dog(String s,

11、int a) name = s; age = a; step = 0; public void run(Dog fast) fast.step+; public static void main(String args) A a = new A(); Dog dog = a.new Dog(Tom, 3); dog.step = 25; dog.run(dog); System.out.println(dog.step); 11.下面程序的运行结果是（ ）。class A int x=1, y=2; double add() return x+y; class B extends A int

12、x=10, y=20; double add() return super.x + super.y; class Takecare public static void main(String args) A a = new A(); B b = new B(); System.out.println(a.add=+a.add(); System.out.println(b.add=+b.add(); 12.下面程序的运行结果是（ ）。for (int i = 0; i 5; i+) switch (i) default: System.out.print(defaultt); case 0:

13、 System.out.print(zerot); i+; break; case 1: System.out.print(onet); case 2: System.out.print(twot); i+; 13.下面程序的运行结果是（ ）。public class Example String str = new String(good); char ch = a, b, c; public void change(String str, char ch) str = test ok; ch0 = g; public static void main(String args) Exampl

14、e example = new Example(); example.change(example.str, example.ch); System.out.print(example.str + and ); System.out.print(example.ch); 14.下面程序的运行结果是（ ）。class A public String Show(D obj) return (A and D); public String Show(A obj) return (A and A); class B extends A public String Show(B obj) return

15、(B and B); public String Show(A obj) return (B and A); class C extends B public String Show(C obj) return (C and C); public String Show(B obj) return (C and B); class D extends B public String Show(D obj) return (D and D); public String Show(B obj) return (D and B); public class main public static v

16、oid main(String args) A a1 = new A(); A a2 = new B(); B b = new B(); C c = new C(); D d = new D(); System.out.println(a1.Show(b); System.out.println(a1.Show(c); System.out.println(a1.Show(d); System.out.println(a2.Show(b); System.out.println(a2.Show(c); System.out.println(a2.Show(d); System.out.prin

17、tln(b.Show(b); System.out.println(b.Show(c); System.out.println(b.Show(d); 15.下面程序的运行结果是（ ）。public class Example extends TT public static void main(String args) Example t = new Example(Tom); public Example(String s) super(s); System.out.println(How do you do?); public Example() this(I am Tom); class

18、 TT public TT() System.out.println(What a pleasure!); public TT(String s) this(); System.out.println(I am + s); 16.下面程序的运行结果是（ ）。public class Example public static void main(String args) for (int i = 0; i 2; i+) resume: for (int j = 0; j 3; j+) for (int k = 0; k A) y=爱; z=情; else y=我; z=她; System.ou

19、t.println( +x+y+z); 19.下面程序的运行结果是（ ）。class TT public TT() System.out.println(What a peasure!); public TT(String s) this(); System.out.println(I am + s); public class Example extends TT public static void main(String args) Example example = new Example(); public Example(String s) super(s); System.out

20、.println(How do youo do?); public Example() this(I am Tom); 20.下面程序的运行结果是（ ）。public class Example public static void main(String args) int count = 0; for (int i = 0; i 3; i+) resume: for (int j = 0; j 4; j+) for (int k = 0; k 5; k+) +count; if (i = 1 & j = 2 & k = 3) break resume; System.out.println

21、(tcount= + count); 21.下面程序的运行结果是（ ）。public class A class Dog private String name; private int age; public int step; Dog(String s, int a) name = s; age = a; step = 0; public void run(Dog fast) fast.step-; public static void main(String args) A a = new A(); Dog dog = a.new Dog(Tom, 3); dog.step = 30;

22、dog.run(dog); System.out.println(dog.step); 22.下面程序的运行结果是（ ）。import java.io.*;public class TestFile public static void main(String args) throws Exception BufferedReader br = new BufferedReader(new InputStreamReader(System.in); BufferedWriter bw = new BufferedWriter(new FileWriter(input.txt); String

23、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(); 23.下面程序的运行结果是（ ）。class A public String Show(D obj) return (A and D); public String Show(A obj) return (A and A); class B extends A public String Show

24、(B obj) return (B and B); public String Show(A obj) return (B and A); class C extends B public String Show(C obj) return (C and C); public String Show(B obj) return (C and B); class D extends B public String Show(D obj) return (D and D); public String Show(B obj) return (D and B); public class main

25、public static void main(String args) A a1 = new A(); A a2 = new B(); B b = new B(); C c = new C(); D d = new D(); System.out.println(a1.Show(b); System.out.println(a1.Show(c); System.out.println(a1.Show(d); System.out.println(a2.Show(b); System.out.println(a2.Show(c); System.out.println(a2.Show(d); System.out