dbquestion.java

一个完整的门户网站,基于JSP环境下开发的,使用SQL数据库.

package com.bwm.database;

import java.sql.*;
import java.util.*;
import javax.servlet.http.HttpServletRequest;
import com.bwm.model.Question;
import com.bwm.core.*;

/**
 * <p>Title: </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2004</p>
 * <p>Company: MR</p>
 * @author BWM
 * @version 1.0
 */

public class Dbquestion extends Question {
    private Question q = new Question();
    public Dbquestion() {
    }

    public Dbquestion(String sql) {
        Connection con = null;
        PreparedStatement ps = null;
        ResultSet rs = null;
        try {
            con = Database.getConnection();
            ps = con.prepareStatement(FinalConstants.SELECT_QUESTION + sql,
                                      ResultSet.TYPE_SCROLL_INSENSITIVE,
                                      ResultSet.CONCUR_READ_ONLY);
            rs = ps.executeQuery();
            if (rs.next()) {
                q.setQid(rs.getInt("lid"));
                q.setAnswer(ParamUtils.getSqlString(rs.getString("answer")));
                q.setQuestion(ParamUtils.getSqlString(rs.getString("question")));
            }
        } catch (SQLException e) {
            System.out.println(e.getMessage());
            e.printStackTrace();
        } finally {
            System.out.println(ps + " Dbquestion(String sql) " + q.getQid());
            try {
                if (ps != null) {
                    ps.close();
                    ps = null;
                }
            } catch (SQLException e) {
                ps = null;
            }
            try {
                if (con != null) {
                    con.close();
                    con = null;
                }
            } catch (SQLException e) {
                con = null;
            }
        }
    }

    public Dbquestion(HttpServletRequest request) {
        q.setAnswer(ParamUtils.getRequestString(request, "answer"));
        q.setQuestion(ParamUtils.getRequestString(request, "question"));
    }

    public boolean Insert() {
        boolean b = false;
        Connection con = null;
        PreparedStatement ps = null;
        try {
            con = Database.getConnection();
            ps = con.prepareStatement(FinalConstants.INSERT_QUESTION);
            ps.setString(1, q.getQuestion());
            ps.setString(2, q.getAnswer());
            if (ps.executeUpdate() > 0) {
                b = true;
            } else {
                b = false;
            }
        } catch (SQLException e) {
            b = false;
            System.out.println(e.getMessage());
            e.printStackTrace();
        } finally {
            System.out.println(ps + " Dbquestion.Insert()");
            try {
                if (ps != null) {
                    ps.close();
                }
            } catch (SQLException e) {
                ps = null;
            }
            try {
                if (con != null) {
                    con.close();
                }
            } catch (SQLException e) {
                con = null;
            }
        }
        return b;
    }

    public Collection Select(String sql) {
        Collection coll = new ArrayList();
        Connection con = null;
        ResultSet rs = null;
        PreparedStatement ps = null;
        try {
            con = Database.getConnection();
            ps = con.prepareStatement(FinalConstants.SELECT_QUESTION + sql);
            rs = ps.executeQuery();
            while (rs.next()) {
                Question qu=new Question();
                qu.setQid(rs.getInt("qid"));
                qu.setAnswer(ParamUtils.getSqlString(rs.getString("answer")));
                qu.setQuestion(ParamUtils.getSqlString(rs.getString("question")));
                coll.add(qu);
            }
        } catch (SQLException ex) {
            System.out.println(ex.getMessage());
        } finally {
            System.out.println(ps + " Dbquestion.Select(String sql) ");
            try {
                if (ps != null) {
                    ps.close();
                    ps = null;
                }
            } catch (SQLException e) {
                ps = null;
            }
            try {
                if (con != null) {
                    con.close();
                    con = null;
                }
            } catch (SQLException e) {
                con = null;
            }
        }
        return coll;
    }

    //页数+SQL条件
    public Collection Select(int page, String sql) {
        Collection coll = new ArrayList();
        Connection con = null;
        ResultSet rs = null;
        PreparedStatement ps = null;
        int tip = FinalConstants.STEP * (page - 1);
        try {
            con = Database.getConnection();
            ps = con.prepareStatement(FinalConstants.SELECT_QUESTION+ sql);
            rs = ps.executeQuery();
            if (tip <= 0) {
                rs.beforeFirst();
            } else {
                if (!rs.absolute(tip)) {
                    rs.beforeFirst();
                }
            }
            for (int i = 1; rs.next() && i <= FinalConstants.STEP; i++) {
                Question qu=new Question();
                qu.setQid(rs.getInt("qid"));
                qu.setAnswer(ParamUtils.getSqlString(rs.getString("answer")));
                qu.setQuestion(ParamUtils.getSqlString(rs.getString("question")));
                coll.add(qu);
            }
        } catch (SQLException ex) {
            System.out.println(ex.getMessage());
        } finally {
            System.out.println(ps + " Dbquestion.Select(int page,String sql) ");
            try {
                if (ps != null) {
                    ps.close();
                    ps = null;
                }
            } catch (SQLException e) {
                ps = null;
            }
            try {
                if (con != null) {
                    con.close();
                    con = null;
                }
            } catch (SQLException e) {
                con = null;
            }
        }
        return coll;
    }

    private boolean Update() {
        boolean b = false;
        Connection con = null;
        PreparedStatement ps = null;
        try {
            con = Database.getConnection();
            ps = con.prepareStatement(FinalConstants.UPDATE_RESOLVENT);
            ps.setString(1, q.getAnswer());
            ps.setString(2, q.getQuestion());
            ps.setInt(3, q.getQid());
            if (ps.executeUpdate() > 0) {
                b = true;
            } else {
                b = false;
            }
        } catch (SQLException e) {
            b = false;
            e.printStackTrace();
        } finally {
            System.out.println(ps + " Dbaffiche.Update() ");
            try {
                if (ps != null) {
                    ps.close();
                }
            } catch (SQLException e) {
                ps = null;
            }
            try {
                if (con != null) {
                    con.close();
                }
            } catch (SQLException e) {
                con = null;
            }
        }
        return b;
    }
    public int getQid() {
        return q.getQid();
    }

    public void setQid(int qid) {
        q.setQid(qid);
    }

    public String getQuestion() {
        return q.getQuestion();
    }

    public void setQuestion(String question) {
        q.setQuestion(question);
        Update();
    }

    public String getAnswer() {
        return q.getAnswer();
    }

    public void setAnswer(String answer) {
        q.setAnswer(answer);
        Update();
    }
}