Java+Jsp+Mysql实现Web毕业设计选题系统

package com.sjsq.service; import com.sjsq.model.Topic; import com.sjsq.util.DB; import java.sql.*; import java.util.ArrayList; import java.util.List; public class TopicManager { public static boolean save(Topic t) { Connection conn = DB.getConn(); String sql = null; boolean b = false; sql = "insert into topic_info values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)"; PreparedStatement pstmt = DB.prepare(conn, sql); try { pstmt.setString(1, t.getNumber()); pstmt.setString(2, t.getName()); pstmt.setString(3, t.getType()); pstmt.setString(4, t.getKind()); pstmt.setString(5, t.getSource()); pstmt.setString(6, t.getStatus()); pstmt.setString(7, t.getContent()); pstmt.setString(8, t.getResult()); pstmt.setString(9, t.getDirection()); pstmt.setString(10, t.getTnumber()); pstmt.setString(11, t.getSnumber()); pstmt.execute(); b = true; } catch (SQLException e) { e.printStackTrace(); } finally { DB.close(pstmt); DB.close(conn); } return b; } public static int getTopics(List<Topic> topics, int pageNo, int pageSize) { int totalRecords = -1; Connection conn = DB.getConn(); String sql = null; sql = "select * from topic_info limit " + (pageNo - 1) * pageSize + "," + pageSize; Statement stmt = DB.getStatement(conn); ResultSet rs = DB.getResultSet(stmt, sql); Statement stmtCount = DB.getStatement(conn); ResultSet rsCount = null; rsCount = DB .getResultSet(stmtCount, "select count(*) from topic_info"); try { rsCount.next(); totalRecords = rsCount.getInt(1); while (rs.next()) { Topic topic = new Topic(); topic.setContent(rs.getString("hcontent")); topic.setDirection(rs.getString("direction")); topic.setKind(rs.getString("hkind")); topic.setName(rs.getString("hname")); topic.setNumber(rs.getString("hno")); topic.setResult(rs.getString("hresult")); topic.setSnumber(rs.getString("sno")); topic.setSource(rs.getString("hsource")); topic.setStatus(rs.getString("hstatus")); topic.setType(rs.getString("htype")); topic.setTnumber(rs.getString("tno")); topics.add(topic); } } catch (SQLException e) { e.printStackTrace(); } finally { DB.close(rsCount); DB.close(stmtCount); DB.close(rs); DB.close(stmt); DB.close(conn); } return totalRecords; } public static boolean deleteByHno(String hno) { boolean b = false; Connection conn = DB.getConn(); String sql = null; sql = "delete from topic_info where hno = '" + hno + "'"; Statement stmt = DB.getStatement(conn); try { DB.executeUpdate(stmt, sql); b = true; } catch (Exception e) { e.printStackTrace(); } finally { DB.close(stmt); DB.close(conn); } return b; } public static boolean check(String tno, String hname) { boolean b = false; Connection conn = DB.getConn(); String sql = null; sql = "select * from topic_info where tno = '" + tno + "'"; Statement stmt = DB.getStatement(conn); ResultSet rs = DB.getResultSet(stmt, sql); try { if (rs.next()) b = true; } catch (SQLException e) { e.printStackTrace(); } finally { DB.close(rs); DB.close(stmt); DB.close(conn); } return b; } public static boolean update(Topic t) { Connection conn = DB.getConn(); String sql = null; boolean b = false; sql = "update topic_info set htype=?, tno=?, hname=?, hsource=?, hkind=?, hstatus=?, hresult=?, sno=?, direction=?, hcontent=? where hno = ?"; PreparedStatement pstmt = DB.prepare(conn, sql); try { pstmt.setString(1, t.getType()); pstmt.setString(2, t.getTnumber()); pstmt.setString(3, t.getName()); pstmt.setString(4, t.getSource()); pstmt.setString(5, t.getKind()); pstmt.setString(6, t.getStatus()); pstmt.setString(7, t.getResult()); pstmt.setString(8, t.getSnumber()); pstmt.setString(9, t.getDirection()); pstmt.setString(10, t.getContent()); pstmt.setString(11, t.getNumber()); pstmt.executeUpdate(); b = true; } catch (SQLException e) { e.printStackTrace(); } finally { DB.close(pstmt); DB.close(conn); } return b; } public static Topic getByNum(String num) { Connection conn = DB.getConn(); String sql = null; sql = "select * from topic_info where hno='" + num + "'"; Statement stmt = DB.getStatement(conn); ResultSet rs = DB.getResultSet(stmt, sql); Topic topic = null; try { if (rs.next()) { topic = new Topic(); topic.setContent(rs.getString("hcontent")); topic.setDirection(rs.getString("direction")); topic.setKind(rs.getString("hkind")); topic.setName(rs.getString("hname")); topic.setNumber(rs.getString("hno")); topic.setResult(rs.getString("hresult")); topic.setSnumber(rs.getString("sno")); topic.setSource(rs.getString("hsource")); topic.setStatus(rs.getString("hstatus")); topic.setType(rs.getString("htype")); topic.setTnumber(rs.getString("tno")); } } catch (SQLException e) { e.printStackTrace(); } finally { DB.close(rs); DB.close(conn); } return topic; } public static List<Topic> getByTno(String num) { Connection conn = DB.getConn(); String sql = null; List<Topic> topics = new ArrayList<Topic>(); sql = "select * from topic_info where tno='" + num + "'"; Statement stmt = DB.getStatement(conn); ResultSet rs = DB.getResultSet(stmt, sql); Topic topic = null; try { while (rs.next()) { topic = new Topic(); topic.setContent(rs.getString("hcontent")); topic.setDirection(rs.getString("direction")); topic.setKind(rs.getString("hkind")); topic.setName(rs.getString("hname")); topic.setNumber(rs.getString("hno")); topic.setResult(rs.getString("hresult")); topic.setSnumber(rs.getString("sno")); topic.setSource(rs.getString("hsource")); topic.setStatus(rs.getString("hstatus")); topic.setType(rs.getString("htype")); topic.setTnumber(rs.getString("tno")); topics.add(topic); } } catch (SQLException e) { e.printStackTrace(); } finally { DB.close(rs); DB.close(conn); } return topics; } public static int query(List<Topic> topics, int pageNo, int pageSize, String str, String kind, String name) { i