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Swing学习总结

news 来源：原创 2024/5/4 18:40:32

（转载）

花了差不多四天时间学习了Swing做的图书管理系统，系统虽然不大，但对我来说做起来还是有一定困难的。

小锋老师讲的还是很不错的，重点、难点都讲得还是很清楚，条理很清晰。通过视频学习我也受益匪浅。

对于一个系统的开发过程我有了更清楚的认识,不管多大的系统都要思路清晰，都要一步一步来，不管是从DAO层开始，还是从View层开始，从每一个功能开始，一步一步地实现。对于JDBC我有更深的理解，增、删、改、查操作更熟练

DAO层的方法根据什么判断返回类型？应该怎么去写？

DAO层主要是操作数据的。。加入是添加，更新，删除返回的是Int 实际操作数据条数如果是查询返回的是List集合，或者ResultSet

1.添加数据

String sql = "insert into t_book values(null,?,?,?,?,?,?)";

PreparedStatement pstmt = conn.prepareStatement(sql);

pstmt.setString(1, book.getBookName());

........

return pstmt.executeUpdate();

2.删除数据

public int bookDelete(Connection conn,String id) throws SQLException{ String sql = "delete from t_bookType where id = ?";

PreparedStatement pstmt = conn.prepareStatement(sql);

pstmt.setString(1, id); return pstmt.executeUpdate(); }

3.修改数据 public int modifyBookType(Connection conn,BookType bookType) throws SQLException{

String sql = "update t_bookType set bookType = ? , bookTypeDesc = ? where id = ?";

PreparedStatement pstmt = conn.prepareStatement(sql);

pstmt.setString(1, bookType.getBookType());

pstmt.setString(2, bookType.getBookTypeDesc());

pstmt.setInt(3, bookType.getId());

return pstmt.executeUpdate(); }

4.查询数据 public ResultSet bookReseach(Connection conn,Book book) throws SQLException{

StringBuffer sb = new StringBuffer("select * from t_book b,t_bookType bt where b.bookTypeId=bt.id");

if(StringUtil.isNotEmpty(book.getBookName())){

sb.append(" and b.bookName like '%"+book.getBookName()+"'"); }

if(StringUtil.isNotEmpty(book.getAuthor())){

sb.append(" and b.autor like '%"+book.getAuthor()+"'"); }

if(StringUtil.isNotEmpty(book.getSex())){

sb.append(" and b.sex = '"+book.getSex()+"'"); }

if(book.getBookTypeId()!=-1){

sb.append(" and b.bookTypeId ="+book.getBookTypeId()); }

PreparedStatement pstmt = conn.prepareStatement(sb.toString());

return pstmt.executeQuery(); }

///条件查询

StringBuffer sb = new StringBuffer("select * from t_bookType");

if(StringUtil.isNotEmpty(bookType.getBookType())){

sb.append(" and bookType like '%"+bookType.getBookType()+"%'"); }

PreparedStatement pstmt = conn.prepareStatement(sb.toString().replace("and", "where"));

return pstmt.executeQuery();

//这个算法不错，非常感谢

5.向JTable中填数据

private void fillBookTable(Book book) {

DefaultTableModel dtm = (DefaultTableModel) tabBook.getModel();

dtm.setRowCount(0); Connection conn = null;

try { conn = dbUtil.getCon();

ResultSet rs = bookDao.bookReseach(conn, book);

while (rs.next()) { Vector vector = new Vector();

vector.add(rs.getInt("id"));

vector.add(rs.getString("bookName"));

vector.add(rs.getString("autor"));

vector.add(rs.getString("sex"));

vector.add(rs.getString("bookDesc"));

vector.add(rs.getString("bookType"));

vector.add(rs.getFloat("price"));

dtm.addRow(vector); } } catch (SQLException e) { e.printStackTrace(); } finally { try { dbUtil.close(conn); } catch (SQLException e) { e.printStackTrace(); } } }

6.控件Combo box中item项中填数据

private void fillBookType() { Connection conn = null;

BookType bookType = null;

try { conn = dbUtil.getCon();

ResultSet rs = bookTypeDao.bookTypeResearch(conn, new BookType());

bookType = new BookType();

bookType.setBookType("请选择...");

bookType.setId(-1);

this.jcbBookType.addItem(bookType);

while (rs.next()) {

bookType = new BookType();

bookType.setId(rs.getInt("id"));

bookType.setBookType(rs.getString("bookType"));

this.jcbBookType.addItem(bookType); } } catch (SQLException e) { e.printStackTrace(); } finally { try { dbUtil.close(conn); } catch (SQLException e) { e.printStackTrace(); } }

}

7.JTable中Mouse的mousePressed事件

private void tabBookTypeMousePressed(java.awt.event.MouseEvent evt) {

int row = tabBookType.getSelectedRow();

this.txtId.setText((String) tabBookType.getValueAt(row, 0));

this.txtBookT.setText((String) tabBookType.getValueAt(row, 1));

this.txtBookTypeDesc.setText((String) tabBookType.getValueAt(row, 2)); }

8.Combo box读数据并显示bookType

String bookType = (String) tabBook.getValueAt(row, 5);

int n = this.jcbBookType.getItemCount();

for (int i = 0; i < n; i++) {

BookType item = (BookType) this.jcbBookType.getItemAt(i);