基于jsp+servlet实现的简单博客系统实例(附源码)

2024-09-05 00:22:21

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这篇文章主要介绍了基于jsp+servlet实现的简单博客系统,以完整实例形式分析了基于jsp+servlet简单博客系统的原理与相关技巧,并附带了完整源码供读者下载学习,需要的朋友可以参考下

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>

}

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;

int out = 0;

try {

conn = ds.getConnection();

ps = conn.prepareStatement(sql);

ps.setString(1, "%" + keyword + "%");

rs = ps.executeQuery();

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));

list.add(blog);

}

} catch (SQLException ex) {

Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex);

} finally {

closeEverything(conn, ps, rs);

}

return list;

}

@Override

public List listBlogByContent(String keyword) {

List<BlogBean> list = new ArrayList<BlogBean>();

BlogBean blog;

String sql = "SELECT * FROM POSTS WHERE CONTENT LIKE ? ORDER BY POSTDATE DESC";

PreparedStatement ps = null;

ResultSet rs = null;

Connection conn = null;

int out = 0;

try {

conn = ds.getConnection();

ps = conn.prepareStatement(sql);

ps.setString(1, "%" + keyword + "%");

rs = ps.executeQuery();

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));

list.add(blog);

}

} catch (SQLException ex) {

Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex);

} finally {

closeEverything(conn, ps, rs);

}

return list;

}

public Set listAllTags() {

tagSet = new HashSet<String>();

String sql = "SELECT TAG FROM POSTS ";

Connection conn = null;

Statement ss = null;

ResultSet rs = null;

try {

conn = ds.getConnection();

ss = conn.createStatement();

rs = ss.executeQuery(sql);

while (rs.next()) {

String tags = rs.getString(1);

String[] Arraytags = tags.split(",");

tagSet.addAll(Arrays.asList(Arraytags));

}

} catch (SQLException ex) {

Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex);

} finally {

closeEverything(conn, ss, rs);

}

return tagSet;

}

public List listBlogByTag(String keyword) {

List<BlogBean> list = new ArrayList<BlogBean>();

BlogBean blog;

String sql = "SELECT * FROM POSTS WHERE TAG LIKE ? ORDER BY POSTDATE DESC";

Connection conn = null;

PreparedStatement ps = null;

ResultSet rs = null;

int out = 0;

try {

conn = ds.getConnection();

ps = conn.prepareStatement(sql);

ps.setString(1, "%" + keyword + "%");

rs = ps.executeQuery();

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));

list.add(blog);

}

} catch (SQLException ex) {

Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex);

} finally {

closeEverything(conn, ps, rs);

}

return list;

}

public List listBlogByDate(String keyword) {

List<BlogBean> list = new ArrayList<BlogBean>();

BlogBean blog;

String sql = "SELECT * FROM POSTS WHERE POSTDATE = ? ORDER BY POSTDATE DESC";

Connection conn = null;

PreparedStatement ps = null;

ResultSet rs = null;

int out = 0;

try {

conn = ds.getConnection();

ps = conn.prepareStatement(sql);

ps.setString(1, keyword );

rs = ps.executeQuery();

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));

list.add(blog);

}

} catch (SQLException ex) {

Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex);

} finally {

closeEverything(conn, ps, rs);

}

return list;

}

public Set listAllCategory() {

categorySet = new HashSet<String>();

String sql = "SELECT CATEGORY FROM POSTS";

Connection conn = null;

Statement ss = null;

ResultSet rs = null;

try {

conn = ds.getConnection();

ss = conn.createStatement();

rs = ss.executeQuery(sql);

while (rs.next()) {

String category = rs.getString(1);

categorySet.add(category);

}

} catch (SQLException ex) {

Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex);

} finally {

closeEverything(conn, ss, rs);

}

return categorySet;

}

public List listBlogByCategory(String keyword) {

List<BlogBean> list = new ArrayList<BlogBean>();

BlogBean blog;

String sql = "SELECT * FROM POSTS WHERE CATEGORY LIKE ?";

Connection conn = null;

PreparedStatement ps = null;

ResultSet rs = null;

int out = 0;

try {

conn = ds.getConnection();

ps = conn.prepareStatement(sql);

ps.setString(1, "%" + keyword + "%");

rs = ps.executeQuery();

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));

list.add(blog);

}

} catch (SQLException ex) {

Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex);

} finally {

closeEverything(conn, ps, rs);

}

return list;

}

private void fillDateMap(){

String sql = "SELECT POSTDATE,COUNT(POSTDATE) FROM POSTS GROUP BY POSTDATE";

Connection conn = null;

Statement ss = null;

ResultSet rs = null;

dateMap = new HashMap<String,Integer>();

try {

conn = ds.getConnection();

ss = conn.createStatement();

rs=ss.executeQuery(sql);

while (rs.next()) {

dateMap.put(rs.getString(1), rs.getInt(2));

}

} catch (SQLException ex) {

Logger.getLogger(BlogRepositoryJDBC.class.getName()).log(Level.SEVERE, null, ex);

} finally {

closeEverything(conn, ss, rs);

}

}

public void test(){

for(Map.Entry<String,Integer> dd: dateMap.entrySet()){

dd.getKey();

dd.getValue();

}

}

public void refreshCache() {

ListAllBlog();

listAllTags();

listAllCategory();

fillDateMap();

}

public ArrayList<BlogBean> getBloglist() {

return bloglist;

}

public Set<String> getTagSet() {

return tagSet;

}

public Set<String> getCategorySet() {

return categorySet;

}

public Map<String, Integer> getDateMap() {

return dateMap;

}

private void closeEverything(Connection conn, Statement ps, ResultSet rs) {

if (rs != null) {

try {

rs.close();

} catch (SQLException ex) {

}

}

if (ps != null) {

try {

ps.close();

} catch (SQLException ex) {

}

}

if (conn != null) {

try {

conn.close();

} catch (SQLException ex) {

}

}

}

}