基于Servlet实现技术问答网站系统

#else

#end

## 标志区域

爱问社区，这里可放logo

## 列表区域

序号

标题

提问时间

提问者

#if( $user )

解答问题

#end

## 问题列表开始

## 每循环一次从 $topics 集合中取出一个 Topic 对象放到 $topic 中

#foreach( $topic in $topics )

$topic.id

$topic.title

http:// $topic.publishTime

$topic.user.username

#if( $user )

解答

#end

## 问题列表结束

发起新问题

提问前台界面代码：

## 登录状态栏开始

## 在 $ 之后表达式之前使用 ! 表示安静模式 ( 静默模式 )

欢迎$!user.username来到爱问社区

#if( $user )

#else

#end

爱问社区，这里可以logo

#if( $askFail )

$askFail

$scope.remove( $session , 'askFail' )

#end

#if( $user )

#else

登录以后才能发起提问，请登录

#end

问题列表

回答Servlet处理代码：

@WebServlet("/answer.do")

public class AnswerServlet extends HttpServlet {

private static final long serialVersionUID = 8578962149437664830L;

@Override

protected void service(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

// 从请求中获得请求参数的值

String id = request.getParameter("id");

if (StringHelper.notEmpty(id)) {

try {

int topicId = Integer.parseInt(id); // 将字符串按照十进制解析问 int 类型数值

// 根据得到的问题的主键查询数据库，得到详细信息

final String SQL = "SELECT id , title , content , publish_time , publish_ip , user_id FROM t_topic WHERE id = ? ";

ResultSet rs = JdbcHelper.query(SQL, topicId);

Topic t = null;

int userId = -1;

if (rs.next()) { // 当根据问题的主键获取到问题信息时

t = new Topic(); // 创建 Topic 对象

t.setId(rs.getInt(1)); // 将结果集中的该行数据封装到 t 对象的 id 属性中

t.setTitle(rs.getString(2));

t.setContent(rs.getString(3));

t.setPublishTime(rs.getTimestamp(4));

t.setPublishIp(rs.getString(5));

userId = rs.getInt(6);

}

JdbcHelper.release(rs); // 关闭结果集

// 获得提问者

final String getUserSQL = "SELECT id , username , password FROM t_user WHERE id = ? ";

rs = JdbcHelper.query(getUserSQL, userId);

if (userId != -1 && rs.next()) {

User u = new User();

// 封装数据

u.setId(rs.getInt(1));

u.setUsername(rs.getString(2));

u.setPassword(rs.getString(3));

// 将获取到的用户数据设置到 Topic 对象的 user 属性中

t.setUser(u);

}

HttpSession session = request.getSession();

session.setAttribute("topic", t);

response.sendRedirect(request.getContextPath() + "/answer.html");

return; // 让方法立即结束

} catch (NumberFormatException e) {

e.printStackTrace();

// response.sendRedirect( request.getContextPath() + "/list.do" );

} catch (SQLException e) {

e.printStackTrace();

// response.sendRedirect( request.getContextPath() + "/list.do" );

}

} else {

// response.sendRedirect( request.getContextPath() + "/list.do" );

}

response.sendRedirect(request.getContextPath() + "/list.do");

}

回答前台代码：

## 登录状态栏开始

## 在 $ 之后表达式之前使用 ! 表示安静模式 ( 静默模式 )

欢迎$!user.username来到爱问社区

#if( $user )

#else

#end

## 标志区域

解答问题

$topic.content

提问时间: $topic.publishTime / 提问者: $topic.user.username

$scope.remove( $session , 'topic' );

发起新问题

以下是使用simditor的方法，需要引入simditor中的css和js样式。simditor下载地址

解答问题Servlet处理，这里需要获取提问者，提问问题以及该问题的已有答案，已有答案回答者。

@WebServlet("/detail.do")

public class DetailServlet extends HttpServlet {

private static final long serialVersionUID = -3202278077673657729L;

@Override

protected void service(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

// 从请求中获得请求参数的值

String id = request.getParameter("id");

if (StringHelper.notEmpty(id)) {

try {

int topicId = Integer.parseInt(id); // 将字符串按照十进制解析问 int 类型数值

// 根据得到的问题的主键查询数据库，得到详细信息

final String SQL = "SELECT id , title , content , publish_time , publish_ip , user_id FROM t_topic WHERE id = ? ";

ResultSet rs = JdbcHelper.query(SQL, topicId);

Topic t = null;

/*int userId = -1;*/

if (rs.next()) { // 当根据问题的主键获取到问题信息时

t = new Topic(); // 创建 Topic 对象

t.setId(rs.getInt(1)); // 将结果集中的该行数据封装到 t 对象的 id 属性中

t.setTitle(rs.getString(2));

t.setContent(rs.getString(3));

t.setPublishTime(rs.getTimestamp(4));

t.setPublishIp(rs.getString(5));

User user = new User();

user.setId(rs.getInt(6));

t.setUser(user);

}

JdbcHelper.release(rs); // 关闭结果集

// 获得提问者

final String getUserSQL = "SELECT id , username , password FROM t_user WHERE id = ? ";

rs = JdbcHelper.query(getUserSQL, t.getUser().getId());

if(rs.next())

{

User u = new User();

// 封装数据

u.setId(rs.getInt(1));

u.setUsername(rs.getString(2));

u.setPassword(rs.getString(3));

// 将获取到的用户数据设置到 Topic 对象的 user 属性中

t.setUser(u);

System.out.println("message username:" + rs.getString(2));

}

JdbcHelper.release(rs); // 关闭结果集

// 获得当前的问题的所有解答

String explainSQL = "SELECT id , content , explain_time , explain_ip , user_id from t_explain where topic_id = ? ";

rs = JdbcHelper.query(explainSQL, topicId);

@SuppressWarnings("unused")

int explainerId = -1;

List explains = new ArrayList<>();

while (rs.next()) {

Explain e = new Explain();

e.setId(rs.getInt(1));

e.setContent(rs.getString(2));

e.setExplainTime(rs.getTimestamp(3));

e.setExplainIp(rs.getString(4));

User user=new User();

user.setId(rs.getInt(5));

e.setUser(user);

explains.add(e);

System.out.println("explain userID:" + rs.getInt(5));

}

// 获得解答者

ListexplainList = new ArrayList();

for(int i=0;i

{

Explain explain1 = explains.get(i);

final String getExplainerSQL = "SELECT id , username , password FROM t_user WHERE id = ? ";

rs = JdbcHelper.query(getExplainerSQL, explain1.getUser().getId());

if (rs.next()) {

User u = new User();

// 封装数据

u.setId(rs.getInt(1));

u.setUsername(rs.getString(2));

u.setPassword(rs.getString(3));

// 将获取到的用户数据设置到 Topic 对象的 user 属性中

explain1.setUser(u);

explainList.add(explain1);

System.out.println("explain username:" + rs.getString(2));

}

JdbcHelper.release(rs); // 关闭结果集

/*t.setExplains(explains); // 将解答设置到 Topic 对象上

*/ }

t.setExplains(explainList);

/*** 为所有的解答，获取解答者的详细信息 ***/

HttpSession session = request.getSession();

session.setAttribute("topic", t);

response.sendRedirect( request.getContextPath() + "/detail.html" );

return; // 让方法立即结束

} catch (NumberFormatException e) {

e.printStackTrace();

} catch (SQLException e) {

e.printStackTrace();

}

} else {

}

response.sendRedirect(request.getContextPath() + "/list.do");

}

解答问题前台显示界面代码;

{

Explain explain1 = explains.get(i);

final String getExplainerSQL = "SELECT id , username , password FROM t_user WHERE id = ? ";

rs = JdbcHelper.query(getExplainerSQL, explain1.getUser().getId());

if (rs.next()) {

User u = new User();

// 封装数据

u.setId(rs.getInt(1));

u.setUsername(rs.getString(2));

u.setPassword(rs.getString(3));

// 将获取到的用户数据设置到 Topic 对象的 user 属性中

explain1.setUser(u);

explainList.add(explain1);

System.out.println("explain username:" + rs.getString(2));

}

JdbcHelper.release(rs); // 关闭结果集

/*t.setExplains(explains); // 将解答设置到 Topic 对象上

*/ }

t.setExplains(explainList);

/*** 为所有的解答，获取解答者的详细信息 ***/

HttpSession session = request.getSession();

session.setAttribute("topic", t);

response.sendRedirect( request.getContextPath() + "/detail.html" );

return; // 让方法立即结束

} catch (NumberFormatException e) {

e.printStackTrace();

} catch (SQLException e) {

e.printStackTrace();

}

} else {

}

response.sendRedirect(request.getContextPath() + "/list.do");

}

解答问题前台显示界面代码;

## 登录状态栏开始

## 在 $ 之后表达式之前使用 ! 表示安静模式 ( 静默模式 )

欢迎$!user.username来到问道

#if( $user )

#else

#end

## 标志区域

$topic.content

提问时间: $topic.publishTime / 提问者: $topic.user.username

#foreach( $ex in $topic.explains)

#end

$scope.remove( $session , 'topic' );

发起新问题

我的解答Servlet处理代码：

@WebServlet("/myAnswer.do")

public class MyAnswerServlet extends HttpServlet {

private static final long serialVersionUID = -3020889403557912216L;

@Override

protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

HttpSession session = request.getSession();

User user = (User) session.getAttribute( "user" ); // 在登录时将 User 对象放入了会话中

Explain ex=null;

final List exp = new ArrayList<>();

if( user != null ) {

int myid=user.getId();

final String SQL = "SELECT id ,content ,explain_time , explain_ip , user_id ,topic_id FROM t_explain WHERE user_id = ? ";

ResultSet rs = JdbcHelper.query(SQL, myid);

//Topic t=null;

//final List explains = new ArrayList<>();

@SuppressWarnings("unused")

int topicId=-1;

try {

while( rs.next() )

{

ex=new Explain();

ex.setId(rs.getInt(1));

ex.setContent(rs.getString(2));

ex.setExplainTime(rs.getTimestamp( 3 ));

ex.setExplainIp(rs.getString(4));

ex.setUser(user);

Topic to=new Topic();

to.setId(rs.getInt(6));

ex.setTopic(to);

topicId=rs.getInt(6);

exp.add(ex);

}

JdbcHelper.release(rs); // 关闭结果集

for(int i = 0 , len = exp.size() ; i < len ; i++)

{

Explain explain=exp.get(i);

Topic tid=explain.getTopic();

final String tSQL = "SELECT id , title , content , publish_time , publish_ip , user_id FROM t_topic WHERE id = ? ";

ResultSet trs = JdbcHelper.query(tSQL, tid.getId());

while(trs.next())

{

Topic t=new Topic();

t.setId(1);

t.setTitle(trs.getString(2));

t.setContent(trs.getString(3));

t.setPublishTime(trs.getTimestamp(4));

t.setPublishIp(trs.getString(5));

ex.setTopic(t);

// explains.add(ex);

System.out.println( "我的tid: " + tid.getId());

}

JdbcHelper.release(trs); // 关闭结果集

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

session.setAttribute("explains", exp);

System.out.println( "我的解答列表: " + exp );

System.out.println( "我的id: " + myid);

response.sendRedirect( request.getContextPath() + "/myAnswer.html");

}

我的解答前台展示页面代码：

首页我的提问

提问注销

#if( $user )

$user.username的所有回答：

#end

#foreach( $ex in $explains)

$ex.content

解答时间: $ex.explainTime

#end

我的提问Servlet处理：

@WebServlet("/myQuestion.do")

public class MyQuestionServlet extends HttpServlet {

private static final long serialVersionUID = -4110483126223561394L;

@Override

protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

HttpSession session = request.getSession();

User user = (User) session.getAttribute( "user" ); // 在登录时将 User 对象放入了会话中

if( user != null ) {

int myid=user.getId();

final String SQL = "SELECT id , title , content, publish_time , publish_ip FROM t_topic WHERE user_id = ? ";

ResultSet rs = JdbcHelper.query(SQL, myid);

final List qtopics = new ArrayList<>();

try {

while( rs.next() ){

Topic t=new Topic();

t.setId(rs.getInt(1));

t.setTitle(rs.getString(2));

t.setContent(rs.getString(3));

t.setPublishTime(rs.getTimestamp(4));

t.setPublishIp(rs.getString(5));

qtopics.add(t);

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

session.setAttribute("qtopics", qtopics);

System.out.println( "我的提问列表: " + qtopics );

System.out.println( "我的id: " + myid);

response.sendRedirect( request.getContextPath() + "/myQuestion.html");

}

我的提问展示代码：

#if($user)

#else

#end

#if( $user )

$user.username的所有提问：

#end

#foreach( $qto in $qtopics)

$qto.content

提问者：$user.username $qto.publishTime

#end

验证码处理的Servlet代码：

@WebServlet(urlPatterns= { "/verify/login.do" , "/verify/regist.do" } )

public class VerifyCodeServlet extends HttpServlet {

private static final long serialVersionUID = 3398560501558431737L;

@Override

protected void service( HttpServletRequest request , HttpServletResponse response )

throws ServletException, IOException {

// 获得当前请求对应的会话对象

HttpSession session = request.getSession();

// 从请求中获得 URI ( 统一资源标识符 )

String uri = request.getRequestURI();

System.out.println( "hello : " + uri );

final int width = 180 ; // 图片宽度

final int height = 40 ; // 图片高度

final String imgType = "jpeg" ; // 指定图片格式 (不是指MIME类型)

final OutputStream output = response.getOutputStream(); // 获得可以向客户端返回图片的输出流 (字节流)

// 创建验证码图片并返回图片上的字符串

String code = GraphicHelper.create( width, height, imgType, output );

System.out.println( "验证码内容: " + code );

// 建立 uri 和相应的验证码的关联 ( 存储到当前会话对象的属性中 )

session.setAttribute( uri , code );

System.out.println( session.getAttribute( uri ) );

}

注册前台界面，有验证码验证功能：

#if( $registFail )

$registFail

$scope.remove( $session , 'registFail' )

#end

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