基于jsp+servlet實現的簡單博客系統實例(附源碼)

2020-07-27 21:31:17

字體：大中小

來源：轉載

供稿：網友

本文實例講述了基于jsp+servlet實現的簡單博客系統。分享給大家供大家參考。具體如下：

沒有用框架寫的小博客，代碼大量重復。

個人感覺重復代碼對于新手還是有好處的，我也是新手，見諒。

完整實例代碼點擊此處本站下載。

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/" + "http://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@Namedpublic 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) {      }    }  }}

3. 運行效果截圖：