JAVA期末大作业.doc

JAVA期末大作业 1. 圆柱体：import java.util.*;public class cylinder public static void main(String args) double radius,height;final double PI=3.14;double area,volume;Scanner s=new Scanner(System.in);radius=s.nextDouble();height=s.nextDouble();area=2*PI*radius*radius+2*PI*radius*height;volume=PI*radius*radius*height;System.out.println(area=+area);System.out.println(volume=+volume);结果：2. heap：import java.util.*;public class heap public static boolean isYearHeap(int x)if(x%4=0|x%400=0)return true;elsereturn false;public static void main(String args)int i;Scanner s=new Scanner(System.in);i=s.nextInt();if(isYearHeap(i)System.out.println(Heap);elseSystem.out.println(Not a heap year);结果：3. 符号：import java.util.*;public class test public static void main(String args) int a=60;/*60=0011 1100*/int b=13;/*13=0000 1101*/int c=0;c=a&b;/*12=0000 1100*/System.out.println(a&b=+c);c=a|b;System.out.println(a|b=+c);c=ab;System.out.println(ab=+c);c=a;System.out.println(a=+c);c=a2;System.out.println(a2;System.out.println(a2=+c);c=a2;System.out.println(a2=+c);结果：4. if语句：import java.util.*;public class area public static void main(String args) double x,y;Scanner s=new Scanner(System.in);x=s.nextDouble();y=s.nextDouble();if(x*y1&x*y4)|(x*y-4)System.out.println(inside);elseSystem.out.println(outside);结果：5. grade：import java.util.*;import javax.swing.JOptionPane;public class grade public static void main(String args) String h=JOptionPane.showInputDialog(Input a letter:);char grade=h.charAt(0);switch(grade)casea:System.out.println(85100);break;caseb:System.out.println(7084);break;casec:System.out.println(6069);break;cased:System.out.println(60);break;default:System.out.println(error);结果：6.package com.tutorialspoint;import java.lang.*;public class BooleanDemo public static void main(String args) / create a Boolean object b Boolean b; / assign value to b b = new Boolean(true); / create a boolean primitive type bool boolean bool; / assign primitive value of b to bool bool = b.booleanValue(); String str = Primitive value of Boolean object + b + is + bool; / print bool value System.out.println( str ); 7. 窗口：import javax.swing.*;public class first public static void main(String args)JFrame first=new JFrame();first.setSize(300,400);first.setTitle(我的窗口);first.setVisible(true);结果：8. for循环：public class TestFor public static void main(Stringargs)int i,j,k,l;for(i=1;i=5;i+)k=5;for(j=0;j=0)if(k0)System.out.print(k);elsel=Math.abs(k)+2;if(l=i)System.out.print(l);elseSystem.out.print( );elseSystem.out.print( );System.out.println();结果：9. importjava.util.Arrays;publicclassTestArraypublicstaticvoidmain(Stringargs)inta=1,3,2,6,5,17,11,7;System.out.println(排序之前数组：);for(inti=0;ia.length;i+)System.out.print(ai+t);Arrays.sort(a);System.out.println(n+排序后的数组：);for(inti=0;ia.length;i+)System.out.print(ai+t);10.数组;public class TestArray public static void main(String args)double value=74.5,56.8,60.7,90.2,70.7;double mean,stdDev,sum=0.0,sumSq=0.0;for(int i=0;ivalue.length;i+)sum+=valuei;sumSq+=valuei*valuei;mean=sum/value.length;System.out.println(mean);stdDev=Math.sqrt(sumSq/value.length-mean*mean);System.out.println(stdDev);结果;11. Arraylist:import java.util.ArrayList;import java.util.List;public class ArraylistTest public static void main(Stringargs) int i,sum=0; double Ave; List List= new ArrayList(); for(i=0;i10;i+) List.add(i); for(i=0;i10;i+) sum+=List.get(i); Ave=sum/10.0; System.out.println(Ave); 结果：12.importjava.util.Arrays;publicclassTestArraypublicstaticvoidmain(Stringargs)inta=newint6;intb=newint6;Arrays.fill(a,4);System.out.println(fill(a,val)的使用;);for(inti=0;ia.length;i+)System.out.print(ai+t);System.out.println(n+fill(a,fromIndex,toIndex,val)的使用：);Arrays.fill(b,2,4,5);for(inti=0;i0)System.out.println(str2+precedes+str1);elseSystem.out.println(str1+precedes+str2);结果：18. Buffer:import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;public class printStdIn public static void main(String args) tryBufferedReader br=new BufferedReader(new InputStreamReader(System.in); String input; while(input=br.readLine()!=null) System.out.println(input); catch(IOException io)io.printStackTrace();结果：19. Bar:public class Main static Bar bar;staticbar=new Bar();public static void main(Stringargs)System.out.println(bar.toString();System.out.println(bar);class Bar public Bar()public String toString()return Bar;结果：20.public class Test int x,y;public static void main(String args) Test test1=new Test();test1.x=1;test1.y=1;Test test2=new Test();test2.x=1;test2.y=1;if(test1.equals(test2)System.out.println(true);elseSystem.out.println(false);public boolean equals(Test t)return (this.x=t.x)&(this.y=t.y);结果：21. For增强：public class TestFor public static void main(Stringargs)int number=0,1,2,3,4,5,6,7,8,9;int sum=0;for(int item:number)sum=sum+item;System.out.println(sum);结果：22. 文件的操作：import java.io.File;public class DeleteFileExa