[理学]学通JAVAWEB的24堂课课后答案代码.doc

Web课后代码：2.1import java.util.Scanner;public class LeapYear public static void main(String args) Scanner scan = new Scanner(System.in); System.out.println(请输入一个年份：); long year = scan.nextLong();/ 接收用户输入 if (year % 4 = 0 & year % 100 != 0 | year % 400 = 0) / 是闰年 System.out.print(year + 是闰年！); else / 不是闰年 System.out.print(year + 不是闰年！);2.2public class Factorial public static void main(String args) int n = 16; long result = 1; if (n 17) System.out.println(n的取值范围是0至17，大于17会超出long类型范围); else if (n = 0) System.out.println(0的阶乘等于1); else for (int i = n; i 0; i-) result *= i; System.out.println(n + 的阶乘等于： + result);2.3public class Book private String name = Java Web开发实战宝典;private int price = 89;public void printInfo()System.out.println(图书的名称为：+name);System.out.println(图书的价格为：+price+元);public static void main(String args) Book book = new Book();book.printInfo();2.4public class Test public static void main(String args) for(int i=1;i=9;i+)/ 循环控制变量从1遍历到9 for(int j=1;j 1000)/判断参数是否小于0throw new MyException(参数大于1000);/异常信息return m;/返回值public static void main(String args)/主方法try/try语句包含可能发生异常的语句int result = speak(1050);/调用方法quotient(catch (MyException e) /处理自定义异常e.printStackTrace();System.out.println(e.getMessage();/输出异常信息catch (ArithmeticException e) /处理ArithmeticException异常System.out.println(参数大于1000);/输出提示信息catch (Exception e) /处理其他异常 System.out.println(程序发生了其他的异常);public class MyException extends Exception /创建自定义异常类String message;/定义String类型变量public MyException(String ErrorMessagr) /父类方法message = ErrorMessagr;public String getMessage()/覆盖getMessage()方法return message;2.6public class Area public static void main(String args) float r = 2.5f;float C = 2 * 3.14f * r;float S = 3.14f * r * r;System.out.println(圆的周长为：+C);System.out.println(圆的面积为：+S);2.7public class ProductPrice public static void main(String args) float money = 1206; / 金额 float rebate = 0f; / 折扣 if (money 200) int grade = (int) money / 200; / 等级 switch (grade) / 根据等级计算折扣比例 case 1: rebate = 0.95f; break; case 2: rebate = 0.90f; break; case 3: rebate = 0.85f; break; case 4: rebate = 0.83f; break; case 5: rebate = 0.80f; break; case 6: rebate = 0.78f; break; case 7: rebate = 0.75f; break; case 8: rebate = 0.73f; break; case 9: rebate = 0.70f; break; case 10: rebate = 0.65f; break; default: rebate = 0.60f; System.out.println(您的累计消费金额为： + money);/ 输出消费金额 System.out.println(您将享受 + rebate + 折优惠！);例 2.8public class Rectangle float length ;float width ;public Rectangle() length = 12.5f;width = 26;public float getArea()return length * width;public static void main(String args) Rectangle rectangle = new Rectangle();System.out.println(矩形的面积为：+rectangle.getArea();2.9public class Test public static void main(String args) for(int i = 1;i 2) System.out.println(不要输入多个汉字); byte codeBit = value.getBytes();/ 获取汉字的字节数组 codeBit0 -= 160;/ 提取字节对应的区码 codeBit1 -= 160; / 组合最终区码编号 String code = formatNumber(codeBit0) + formatNumber(codeBit1); System.out.println(code); catch (IOException e) e.printStackTrace(); 4.1 应用switch语句判断学生成绩var grade=80;if(grade=60&grade=70&grade=80&grade=90&grade=100)alert(特优！);4.2 for循环计算10以内奇数的和 var sum = 0; /定义保存计算结果的变量for (i = 1; i 10; i +) if(i%2=1)sum += i; /累加i的值alert(10以内所有奇数的和是： + sum);/输出计算结果4.3 验证年龄在0-100之间 function check()var age = document.getElementById(age);if(age.value=null|age.value=)alert(请输入年龄！);age.focus();return;if(isNaN(age.value)alert(年龄必须为数字！);age.focus();return;if(!isNaN(age.value)if(age.value100|age.value=0)alert(年龄必须在0100之间！);age.focus();return;document.getElementById(myform).submit(); 4.4 去除字符串中的左右数字 function trim(str)var regExp = /(d*)|(d*$)/g; /验证左右空格的正则表达式 str = str.replace(regExp,); /去掉字符串的左右空格return str;function convert()var str = document.getElementById(str).value;if(str=)alert(请输入字符串！);document.getElementById(str).focus();return;document.getElementById(convertStr).value = trim(str);4.5 验证字符串是否包含特殊字符 function checkEspecialCode(str)var regExpress = /;&=#/; /特殊字符正则表达式if(regExpress.test(str)/测试字符串是否包含指定的特殊字符return false;return true;function check()var userName = document.getElementById(username).value;var limitNum = 10;if(userName=)alert(请输入用户名！);document.getElementById(username).focus();return;if(!checkEspecialCode(userName)alert(您输入的用户名中包含无效字符！);document.getElementById(username).focus();return;document.getElementById(myform).submit(); 4.6 验证E-mail和密码 function check()var email = document.getElementById(email);var pwd = document.getElementById(pwd);if(pwd.value.length6)alert(密码长度不得小于6位！);pwd.focus();return;if(email.value=null|email.value=)/判断文本框是否为空 alert(请输入E-mail地址！);email.focus();return;var regExpression = /w+(-+.w+)*w+(-.w+)*.w+(-.w+)*/;var objExp = new RegExp(regExpression);/创建正则表达式对象 if(objExp.test(email.value)=false)/通过 test()函数测试字符串是否与表达式的模式匹配 alert(您输入的E-mail地址不正确！);email.focus();/使文本框获得焦点 return;document.getElementById(myform).submit();4.7 验证手机号码是否正确function checkPhone()var mobileNo = document.getElementById(mobileNo);var regExpression = /(86)?(13d9)|(150,1,2,3,5,6,7,8,9d8)|(180,1,2,3,5,6,7,8,9d8)$/;if(!regExpression.test(mobileNo.value)alert(您输入的手机号码有误！);mobileNo.focus();return;document.getElementById(myform).submit();4.8 计算两个日期相差的小时数 function checkDate(dateStr)if(dateStr=|dateStr=null)return false;elseif(dateStr.indexOf(-)!=-1)var dateArr = dateStr.split(-);var year = dateArr0;/提取年份var month = dateArr1;/提取月份var day = dateArr2;/提取日/如果年份、月份、日期 不是数字或者=0，返回falseif(isNaN(year)|year=0)return false;if(isNaN(month)|month12)return false;if(isNaN(day)|day31)return false;/年份能被4整除并且不能被100整除，或者能被400整除，则为闰年if(year%4=0&year%100!=0)|(year%400=0)if(month=2)/闰年的2月 if(day29)return false;else/不是闰年的2月 if(month=2)if(day28)return false;/1、3、5、7、8、10、12月份为31天 var m1 = new Array(1,3,5,7,8,10,12);for(var i=0;i31) return false;/4、6、9、12月份为31天 var m2 = new Array(4,6,9,11);for(var j=0;j30) return false;elsereturn false;return true;function getHours(date1,date2)var date1Str = date1.split(-);/var date1Obj = new Date(date1Str0,(date1Str1-1),date1Str2);var date2Str = date2.split(-);var date2Obj = new Date(date2Str0,(date2Str1-1),date2Str2);var t1 = date1Obj.getTime();var t2 = date2Obj.getTime();var datetime=1000*60*60*24;/一天时间的毫秒值 var minusDays = Math.floor(t2-t1)/datetime);var days = Math.abs(minusDays);/如果结果为负数，取绝对值return days*24;function check()var start_date = document.getElementById(start_date).value;var end_date = document.getElementById(end_date).value;if(start_date=)alert(请输入开始日期！);return;elseif(!checkDate(start_date)alert(您输入的开始日期无效！);return;if(end_date=)alert(请输入终止日期！);return;elseif(!checkDate(end_date)alert(您输入的终止日期无效！);return;document.getElementById(minusDay).value = getHours(start_date,end_date);4.9 function compart(lang_num)var result=0;/保存分位后的结果 var dec=;/保存小数点后的数字 if(lang_num0)/如果包含小数 dec=lang_num.substr(decimal);/截取小数点后的值res=lang_num.substr(0,decimal);/截取小数点前的整数值elseres=lang_num;for(var i=res.length;i0;i=i-4)/循环整数 ，从整数的个位开始循环 if(i-40)temp=,+res.substr(i-4,4)+temp;elsetemp=res.substr(0,i)+tempresult =temp+dec;return result;function convert()var lang_number = document.getElementById(lang_number).value;if(lang_number=)alert(请输入数字！);document.getElementById(lang_number).focus();return;if(isNaN(lang_number)alert(您输入的数字无效！);document.getElementById(lang_number).focus();return;document.getElementById(result_num).value = compart(lang_number);5.0屏蔽鼠标右键function rightKey()if(event.button=2)/判断是否按下的是鼠标右键event.returnValue=false;alert(禁止使用鼠标右键！);document.onmousedown=rightKey;/当鼠标键被按下时，调用rightKey函数5.2 My JSP index.jsp starting page %for (int i = 0; i 5.5 % String str = n; for(int i = 1;i = 9; i+) for(int j = 1 ;j 5.6根据数据库中信息显示列表内容5.7 function myCheck()var pass = form.pwd.value;var pass2 = form.pwd1.value;if(pass != pass2)window.alert(输入的密码不一致);return false; form.submit(); My JSP update.jsp starting page %out.println(alert(信息修改成功！);window.location.href=index.jsp;);/给出提示信息后，转发至index.jsp页%5.8 function trigger(opt)/opt表示现有可选项的数目form1.CardType.optionsopt=new Option(form1.CardType.optionsopt?form1.CardType.optionsopt.innerText+String.fromCharCode(event.keyCode)String.fromCharCode(event.keyCode)form1.CardType.selectedIndex=opt; function edit(opt) /opt表示现有可选项的数目 if(form1.CardType.optionsopt) if(event.keyCode=8) var str=form1.CardType.optionsopt.innerText; var len=str.length; form1.CardType.optionsopt.innerText=str.substring(0,len-1); if(form1.CardType.optionsopt.innerText=) form1.CardType.remove(opt); form1.CardType.selectedIndex=1; ; if(event.keyCode=32) form1.CardType.optionsopt.innerText+= ; function mySubmit()window.alert(修改成功); 6.1 % int cou; if(application.getAttribute(c)=null) cou=1; else cou=Integer.parseInt(application.getAttribute(c).toString(); application.setAttribute(c,cou); int mycount= Integer.parseInt(application.getAttribute(c).toString(); out.println(人数统计：+mycount+人); application.setAttribute(c,mycount+1); String username=new String(request.getParameter(username).getBytes(iso-8859-1),GBK); List list=null; if(application.getAttribute(username)=null) list=new ArrayList(); else list=(List)application.getAttribute(username); list.add(username); application.setAttribute(username, list); if(application.getAttribute(username)!=null) List list_temp=(List)application.getAttribute(username); if(list_temp.size()=1)out.println(欢迎你,+list_temp.get(list_temp.size()-1)+你是我们网站的第一个访客!);elseout.println(你的上一个访客是：list_temp.get(list_temp.size()-2); %6.2import java.io.IOException;import java.io.PrintWriter;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;import java.sql.Statement;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class IpServlet extends HttpServlet public IpServlet() super();public void destroy() super.destroy(); public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException response.setContentType(text/html);PrintWriter out = response.getWriter();out.println();out.println();out.println( A Servlet);out.println( );out.print( This is );out.p