lab6.zip

package dao.Impl; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.util.ArrayList; import java.util.List; import bean.Student; import dao.StudentDao; import util.DatabaseBean; public class StudentDaoImpl implements StudentDao{ Connection conn = null; PreparedStatement pstmt = null; ResultSet rs = null; @Override public List<Student> findAll() { List<Student> students = new ArrayList<Student>(); try { conn=DatabaseBean.getConnection(); String sql = "select stuno,stuname,stusex from t_student"; pstmt = conn.prepareStatement(sql); rs = pstmt.executeQuery(); while (rs.next()) { Student stu = new Student(); stu.setStuno(rs.getString("stuno")); stu.setStuname(rs.getString("stuname")); stu.setStusex(rs.getString("stusex")); students.add(stu); } } catch (Exception e) { e.printStackTrace(); } finally { DatabaseBean.close(rs, pstmt, conn); } return students; } @Override //模糊查询 public List<Student> selectStudentByStuname(String stuname) { List<Student> students = new ArrayList<Student>(); try { conn=DatabaseBean.getConnection(); String sql = "select stuno,stuname,stusex from t_student where stuname like ?"; pstmt = conn.prepareStatement(sql); pstmt.setString(1, "%" + stuname + "%"); rs = pstmt.executeQuery(); while (rs.next()) { Student stu = new Student(); stu.setStuno(rs.getString("stuno")); stu.setStuname(rs.getString("stuname")); stu.setStusex(rs.getString("stusex")); students.add(stu); } } catch (Exception e) { e.printStackTrace(); } finally { DatabaseBean.close(rs, pstmt, conn); } return students; } @Override //删除操作 public boolean deleteStudent(String stuno) { try { conn=DatabaseBean.getConnection(); String sql = "delete from t_student where stuno=?"; pstmt = conn.prepareStatement(sql); pstmt.setString(1,stuno); int result = pstmt.executeUpdate(); //pstmt.close(); //conn.close(); if(result>0) { return true; } } catch (Exception e) { e.printStackTrace(); } finally { DatabaseBean.close(rs, pstmt, conn); } return false; } @Override public boolean saveStudent(Student stu) { try { conn=DatabaseBean.getConnection(); //String sql = "insert into t_student(stuno,stuname,stusex) values(?,?,?)"; String sql = "update t_student set stuname=?,stusex=? where stuno=?"; pstmt = conn.prepareStatement(sql); pstmt.setString(1, stu.getStuname()); pstmt.setString(2, stu.getStusex()); pstmt.setString(3, stu.getStuno()); int result = pstmt.executeUpdate(); //pstmt.close(); //conn.close(); if(result>0) { return true; } } catch (Exception e) { e.printStackTrace(); } finally { DatabaseBean.close(rs, pstmt, conn); } return false; } }