设为首页收藏本站
开启辅助访问

在路上

 找回密码
 立即注册
在路上 › 站点首页 ›学习 › 查看内容

Java使用cookie显示最近查看过的书

2016-7-29 15:37| 发布者: zhangjf| 查看: 666| 评论: 0

摘要: 本文实例为大家分享了Java使用cookie显示最近查看过的书的相关方法，供大家参考，具体内容如下 1.ben包 import java.io.Serializable; public class Book implements Serializable { private String id; priva ...

本文实例为大家分享了Java使用cookie显示最近查看过的书的相关方法，供大家参考，具体内容如下

1.ben包

  2. import java.io.Serializable;
  4. public class Book implements Serializable {
  5. private String id;
  6. private String name;
  7. private String price;
  8. private String auth;
  9. private String publish;
  10. private String description;
  12. public Book() {
  13. }
  15. public Book(String id, String name, String price, String auth,
  16. String publish, String description) {
  17. super();
  18. this.id = id;
  19. this.name = name;
  20. this.price = price;
  21. this.auth = auth;
  22. this.publish = publish;
  23. this.description = description;
  24. }
  26. public String getDescription() {
  27. return description;
  28. }
  30. public void setDescription(String description) {
  31. this.description = description;
  32. }
  34. public String getId() {
  35. return id;
  36. }
  37. public void setId(String id) {
  38. this.id = id;
  39. }
  40. public String getName() {
  41. return name;
  42. }
  43. public void setName(String name) {
  44. this.name = name;
  45. }
  46. public String getPrice() {
  47. return price;
  48. }
  49. public void setPrice(String price) {
  50. this.price = price;
  51. }
  52. public String getAuth() {
  53. return auth;
  54. }
  55. public void setAuth(String auth) {
  56. this.auth = auth;
  57. }
  58. public String getPublish() {
  59. return publish;
  60. }
  61. public void setPublish(String publish) {
  62. this.publish = publish;
  63. }
  65. }
复制代码

2.Dao包

  2. import java.util.LinkedHashMap;
  3. import java.util.Map;
  5. import cn.huiyu.ben.Book;
  9. public class BookDao {
  10. private static Map<String,Book> bookMap = new LinkedHashMap<String, Book>();
  11. private BookDao() {
  12. }
  13. static{
  14. bookMap.put("1", new Book("1","1111","11.0","zqwang","111出版社","111111111"));
  15. bookMap.put("2", new Book("2","2222","22.0","zqwang","222出版社","222222222"));
  16. bookMap.put("3", new Book("3","3333","33.0","zqwang","333出版社","333333333"));
  17. }
  19. public static Map<String,Book> getBooks(){
  20. return bookMap;
  21. }
  23. public static Book getBook(String id){
  24. return bookMap.get(id);
  25. }
  26. }
复制代码

3.servlet

  2. public void doGet(HttpServletRequest request, HttpServletResponse response)
  3. throws ServletException, IOException {
  4. response.setContentType("text/html;charset=utf-8");
  5. //1.查询数据库中所有的书展示
  6. Map<String,Book> map = BookDao.getBooks();
  7. for(Map.Entry<String , Book> entry : map.entrySet()){
  8. Book book = entry.getValue();
  9. response.getWriter().write("<a href='"+request.getContextPath()+"/servlet/BookInfoServlet?id="+book.getId()+"'>"+book.getName()+"</a><br>");
  10. }
  11. response.getWriter().write("<hr>");
  13. //2.显示之前看过的书
  14. Cookie [] cs = request.getCookies();
  15. Cookie findC = null;
  16. if(cs!=null){
  17. for(Cookie c : cs){
  18. if("last".equals(c.getName())){
  19. findC = c;
  20. }
  21. }
  22. }
  23. if(findC == null){
  24. response.getWriter().write("没有看过任何书!");
  25. }else{
  26. response.getWriter().write("您曾经浏览过的书:<br>");
  27. String[] ids = findC.getValue().split(",");
  28. for(String id : ids){
  29. Book book = BookDao.getBook(id);
  30. response.getWriter().write(book.getName()+"<br>");
  31. }
  32. }
  33. }
复制代码

4.servlet

  2. public void doGet(HttpServletRequest request, HttpServletResponse response)
  3. throws ServletException, IOException {
  4. response.setContentType("text/html;charset=utf-8");
  5. //1.获取要看的书的id,查询数据库找出书,输出书的详细信息
  6. String id = request.getParameter("id");
  7. Book book = BookDao.getBook(id);
  8. if(book==null){
  9. response.getWriter().write("找不到这本书!");
  10. return;
  11. }else{
  12. response.getWriter().write("<h1>书名:"+book.getName()+"</h1>");
  13. response.getWriter().write("<h3>作者:"+book.getAuth()+"</h3>");
  14. response.getWriter().write("<h3>售价:"+book.getPrice()+"</h3>");
  15. response.getWriter().write("<h3>出版社:"+book.getPublish()+"</h3>");
  16. response.getWriter().write("<h3>描述信息:"+book.getDescription()+"</h3>");
  17. }
  19. //2.发送cookie保存最后看过的书
  20. // --- 1 --> 1
  21. // 1 --2,1 --> 2,1
  22. // 2,1--3,2,1 --> 3,2,1
  23. // 3,2,1 -- 4,3,2 --> 4,3,2
  24. // 4,3,2 --3,4,2 --> 3,4,2
  25. String ids = "";
  27. Cookie [] cs = request.getCookies();
  28. Cookie findC = null;
  29. if(cs!=null){
  30. for(Cookie c : cs){
  31. if("last".equals(c.getName())){
  32. findC = c;
  33. }
  34. }
  35. }
  37. if(findC == null){
  38. //说明之前没有看过书的记录
  39. ids += book.getId();
  40. }else{
  41. //说明之前有历史看过的书的记录,需要根据历史记录算一个新的记录出来
  42. String [] olds = findC.getValue().split(",");
  43. StringBuffer buffer = new StringBuffer();
  44. buffer.append(book.getId()+",");
  45. for(int i = 0;i<olds.length && buffer.toString().split(",").length<3 ;i++){
  46. String old = olds[i];
  47. if(!old.equals(book.getId())){
  48. buffer.append(old+",");
  49. }
  50. }
  51. ids = buffer.substring(0, buffer.length()-1);
  52. }
  56. Cookie lastC = new Cookie("last",ids);
  57. lastC.setMaxAge(3600*24*30);
  58. lastC.setPath(request.getContextPath());
  59. response.addCookie(lastC);
  60. }
复制代码

以上就是本文的全部内容，希望对大家学习Java使用cookie显示最近查看过的书的方法有所帮助。

收藏 邀请
上一篇：java实现一个简单TCPSocket聊天室功能分享下一篇：java实现Base64加密解密算法

最新评论

相关分类

小黑屋|在路上 ( 蜀ICP备15035742号-1 )  

;

GMT+8, 2025-5-6 10:30

Copyright 2015-2025 djqfx

返回顶部