21paradox通过本文主要向大家介绍了jsp servlet实例,jsp调用servlet实例,jsp servlet,jsp servlet javabean,jsp servlet mysql等相关知识,希望对您有所帮助,也希望大家支持linkedu.com www.linkedu.com
本文实例讲述了基于jsp+servlet实现的简单博客系统。分享给大家供大家参考。具体如下:
没有用框架写的 小博客, 代码大量重复。
个人感觉重复代码对于新手还是有好处的,我也是新手,见谅。
完整实例代码点击此处本站下载。
1. servlet
/* * To change this template, choose Tools | Templates * and open the template in the editor. */ package Servlet; import blog.BlogBean; import blog.BlogRepositoryJDBC; import blog.PagerUtil; import java.io.IOException; import java.io.PrintWriter; import java.net.URLDecoder; import java.util.List; import javax.enterprise.context.RequestScoped; import javax.enterprise.context.SessionScoped; import javax.inject.Inject; import javax.inject.Named; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; @WebServlet(name = "PageListServlet", urlPatterns = {"/page/*", ""}) public class ListAllServlet extends HttpServlet { @Inject private BlogRepositoryJDBC blogdao; @Inject private PagerUtil pagerUtil; protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { int pg; String s = request.getRequestURI(); String searchContent = request.getParameter("search"); if (s.matches(request.getContextPath() + "/page/" + "\\d")) { String pgnum = s.replaceAll(request.getContextPath() + "/page/", ""); pg = Integer.parseInt(pgnum); } else if (s.matches(request.getContextPath() + "/")) { pg = 1; } else { getServletContext().getRequestDispatcher("/errorpage.jsp").forward(request, response); return; } List<BlogBean> bloglist; boolean isNullRequest = (searchContent == null || "".equals(searchContent)); if (isNullRequest) { bloglist = blogdao.getBloglist(); } else { bloglist = blogdao.listBlogByKey(searchContent); } if (!pagerUtil.isValidPg(bloglist, pg)) { getServletContext().getRequestDispatcher("/errorpage.jsp").forward(request, response); return; } pagerUtil.fillValue(bloglist, pg); String pageURLBase = getServletContext().getContextPath(); String pageURLparam = isNullRequest ? "" : "?search=" + searchContent; request.setAttribute("pageURLBase", pageURLBase); request.setAttribute("pageURLparam", pageURLparam); request.setAttribute("bloglist", bloglist); getServletContext().getRequestDispatcher("/blog.jsp").forward(request, response); } @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } @Override public String getServletInfo() { return "Short description"; }// </editor-fold> }</div>
2. dao
package blog; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import java.util.Arrays; import java.util.Date; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.Set; import java.util.logging.Level; import java.util.logging.Logger; import javax.annotation.PostConstruct; import javax.annotation.Resource; import javax.enterprise.context.ApplicationScoped; import javax.inject.Inject; import javax.inject.Named; import javax.sql.DataSource; @ApplicationScoped @Named public class BlogRepositoryJDBC implements BlogRepository { @Resource(lookup = "jdbc/sample") private DataSource ds; private ArrayList<BlogBean> bloglist; private Set<String> tagSet; private Set<String> categorySet; private Map<String,Integer> dateMap; @PostConstruct private void init() { refreshCache(); } @Override public int addBlog(BlogBean blogi) { String sql = "INSERT INTO POSTS VALUES (?,?,?,?,?)"; Connection conn = null; PreparedStatement ps = null; int out = 0; try { conn = ds.getConnection(); ps = conn.prepareStatement(sql); ps.setString(1, blogi.getBlogTitle()); ps.setString(2, blogi.getCategory()); ps.setString(3, blogi.getTag()); ps.setDate(4, new java.sql.Date(blogi.getPostDate().getTime())); ps.setString(5, blogi.getContent()); out = ps.executeUpdate(); } catch (SQLException ex) { Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex); } finally { closeEverything(conn, ps, null); } refreshCache(); return out; } @Override public int deleteBlog(String blogName) { String sql = "DELETE FROM POSTS WHERE HEAD = ?"; Connection conn = null; PreparedStatement ps = null; int out = 0; try { conn = ds.getConnection(); ps = conn.prepareStatement(sql); ps.setString(1, blogName); out = ps.executeUpdate(); } catch (SQLException ex) { Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex); } finally { closeEverything(conn, ps, null); } refreshCache(); return out; } @Override public int updateBlog(BlogBean blog, String oldhead) { String sql = "UPDATE POSTS SET HEAD=?,CATEGORY=?,TAG=?,POSTDATE=?,CONTENT=? WHERE HEAD=?"; PreparedStatement ps = null; Connection conn = null; int out = 0; try { conn = ds.getConnection(); ps = conn.prepareStatement(sql); ps.setString(1, blog.getBlogTitle()); ps.setString(2, blog.getCategory()); ps.setString(3, blog.getTag()); ps.setDate(4, new java.sql.Date(blog.getPostDate().getTime())); ps.setString(5, blog.getContent()); ps.setString(6, oldhead); out = ps.executeUpdate(); } catch (SQLException ex) { Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex); } finally { closeEverything(conn, ps, null); } refreshCache(); return out; } @Override public List<BlogBean> ListAllBlog() { bloglist = new ArrayList<BlogBean>(); BlogBean blog; String sql = "SELECT * FROM POSTS ORDER BY POSTDATE DESC"; Connection conn = null; Statement ss = null; ResultSet rs = null; int out = 0; try { conn = ds.getConnection(); ss = conn.createStatement(); rs = ss.executeQuery(sql); while (rs.next()) { blog = new BlogBean(); blog.setBlogTitle(rs.getString(1)); blog.setCategory(rs.getString(2)); blog.setTag(rs.getString(3)); blog.setPostDate(rs.getDate(4)); blog.setContent(rs.getString(5)); bloglist.add(blog); } } catch (SQLException ex) { Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex); } finally { closeEverything(conn, ss, rs); } return bloglist; } @Override public List listBlogByKey(String keyword) { List<BlogBean> list = new ArrayList<BlogBean>(); BlogBean blog; String sql = "SELECT * FROM POSTS WHERE HEAD LIKE ? ORDER BY POSTDATE DESC"; Connection conn = null; PreparedStatement ps = null; ResultSet rs = null;