下面的代码是读取文本文件的例子,程序会读取texttxt文件,并将它的内容显示出来。
1importjavaio;
2importjavaioFile;
3importjavaioFileReader;
4importjavaio;
5importjavaioIOException;
6
7publicclass
8{
9publicstaticvoidmain(String[]args)
10{
11Filefile=newFile("testtxt");
12contents=new();
13reader=null;
14
15try
16{
17reader=new(newFileReader(file));
18Stringtext=null;
19
20//repeatuntilalllinesisread
21while((text=readerreadLine())!=null)
22{
23contentsappend(text)
24append(SystemgetProperty(
25"lineseparator"));
26}
27}catch(e)
28{
29e();
30}catch(IOExceptione)
31{
32e();
33}finally
34{
35try
36{
37if(reader!=null)
38{
39readerclose();
40}
41}catch(IOExceptione)
42{
43e();
44}
45}
46
47//showfilecontentshere
48Systemoutprintln(contentstoString());
前段时间正好做了,导入和导出的,你自己看吧
/导出数据为XLS格式
@param fos
@param bo
/
public void writeExcelBo(FileOutputStream fos, javautilVector ve)
{
jxlwriteWritableWorkbook wwb;
try
{
wwb= WorkbookcreateWorkbook(fos);
jxlwriteWritableSheet ws= wwbcreateSheet("booksheet", 10);
wsaddCell(new jxlwriteLabel(0, 1, "书目ID"));
wsaddCell(new jxlwriteLabel(1, 1, "ISBN"));
wsaddCell(new jxlwriteLabel(2, 1, "定价"));
wsaddCell(new jxlwriteLabel(3, 1, "书名"));
wsaddCell(new jxlwriteLabel(4, 1, "原书名"));
wsaddCell(new jxlwriteLabel(5, 1, "副题名"));
wsaddCell(new jxlwriteLabel(6, 1, "著者"));
wsaddCell(new jxlwriteLabel(7, 1, "译者"));
wsaddCell(new jxlwriteLabel(8, 1, "版次"));
wsaddCell(new jxlwriteLabel(9, 1, "出版地"));
wsaddCell(new jxlwriteLabel(10, 1, "出版社"));
wsaddCell(new jxlwriteLabel(11, 1, "出版日期"));
wsaddCell(new jxlwriteLabel(12, 1, "页数"));
wsaddCell(new jxlwriteLabel(13, 1, "书高"));
wsaddCell(new jxlwriteLabel(14, 1, "装帧"));
wsaddCell(new jxlwriteLabel(15, 1, "丛书名"));
wsaddCell(new jxlwriteLabel(16, 1, "一般性附注项"));
wsaddCell(new jxlwriteLabel(17, 1, "简介"));
wsaddCell(new jxlwriteLabel(18, 1, "主题词"));
wsaddCell(new jxlwriteLabel(19, 1, "中图法分类"));
wsaddCell(new jxlwriteLabel(20, 1, "更新日期"));
wsaddCell(new jxlwriteLabel(21, 1, "本数"));
book=new Book[vesize()];
for (int i= 0; i < vesize(); i++)
{
book[i]= (Book)veget(i);
wsaddCell(new jxlwriteLabel(0, i + 2, "" + book[i]getBookId()));
wsaddCell(new jxlwriteLabel(1, i + 2, book[i]getIsbn()));
wsaddCell(new jxlwriteLabel(2, i + 2, "" + book[i]getPrice()));
wsaddCell(new jxlwriteLabel(3, i + 2, book[i]getBookTitle()));
wsaddCell(new jxlwriteLabel(4, i + 2, book[i]getOldFilename()));
wsaddCell(new jxlwriteLabel(5, i + 2, book[i]getSubTitle()));
wsaddCell(new jxlwriteLabel(6, i + 2, book[i]getWriter()));
wsaddCell(new jxlwriteLabel(7, i + 2, book[i]getTranscribe()));
wsaddCell(new jxlwriteLabel(8, i + 2, "" + book[i]getVersion()));
wsaddCell(new jxlwriteLabel(9, i + 2, book[i]getPublishCity()));
wsaddCell(new jxlwriteLabel(10, i + 2, book[i]getPublisher()));
wsaddCell(new jxlwriteLabel(11, i + 2, book[i]getPublishDate()toString()));
wsaddCell(new jxlwriteLabel(12, i + 2, "" + book[i]getPage()));
wsaddCell(new jxlwriteLabel(13, i + 2, "" + book[i]getHight()));
wsaddCell(new jxlwriteLabel(14, i + 2, book[i]getInstall()));
wsaddCell(new jxlwriteLabel(15, i + 2, book[i]getSeries()));
wsaddCell(new jxlwriteLabel(16, i + 2, book[i]getNotes()));
wsaddCell(new jxlwriteLabel(17, i + 2, book[i]getPrecisnotes()));
wsaddCell(new jxlwriteLabel(18, i + 2, book[i]getSubject()));
wsaddCell(new jxlwriteLabel(19, i + 2, book[i]getCls()replaceAll("_", "")));
wsaddCell(new jxlwriteLabel(20, i + 2, book[i]getUpdatedate()toString()));
wsaddCell(new jxlwriteLabel(21, i + 2, "0"));
}
jxlwriteWritableFont wfc=
new jxlwriteWritableFont(
WritableFontARIAL,
255,
WritableFontBOLD,
false,
UnderlineStyleNO_UNDERLINE,
jxlformatColourBLACK);
jxlwriteWritableCellFormat wcfFC= new jxlwriteWritableCellFormat(wfc);
wsaddCell(new jxlwriteLabel(0, 0, "为保证您提交定单的稳定和正确,导入定单时候请勿更改此表格式(请勿更改书目ID,订购本数自行添加!)"));
wwbwrite();
//关闭Excel工作薄对象
wwbclose();
} catch (IOException e)
{} catch (RowsExceededException e)
{} catch (WriteException e)
{}
}
//导入EXCEL
if (fgetName()indexOf("xls") > 0)
{
try
{
fis= new FileInputStream(f);
BookBean bob= new BookBean();
UserBean usb= new UserBean();
jxlWorkbook rwb= WorkbookgetWorkbook(fis);
jxlSheet sh= rwbgetSheet(0);
int rowCount= shgetRows();
SimpleDateFormat sdf= new SimpleDateFormat("dd/MM/yyyy");
book= new Book[rowCount - 1];
for (int i= 1; i < rowCount; i++)
{
book[i - 1]= new Book();
jxlCell[] ce= shgetRow(i);
book[i - 1]setIsbn(ce[0]getContents()toString());
book[i - 1]setSeries(ce[1]getContents()toString());
book[i - 1]setBookTitle(ce[2]getContents()toString());
book[i - 1]setWriter(ce[3]getContents()toString());
book[i - 1]setTranscribe(ce[4]getContents()toString());
book[i - 1]setPublisher(ce[5]getContents()toString());
book[i - 1]setPublishDate(sdfparse(ce[6]getContents()toString(), new ParsePosition(0)));
book[i-1]setVersion(IntegerparseInt(ce[7]getContents()toString()));
book[i-1]setPage(IntegerparseInt(ce[8]getContents()toString()));
book[i-1]setCls(ce[9]getContents()toString());
book[i-1]setPrecisnotes(ce[10]getContents()toString());
book[i-1]setInstall(ce[11]getContents()toString());
book[i-1]setPrice(FloatparseFloat(ce[12]getContents()toString()));
book[i-1]setUserid(usbgetUser()getUserid());
getVector()addElement(book[i - 1]);
}
rwbclose();
fisclose();
} catch (FileNotFoundException e)
{} catch (BiffException e)
{} catch (IOException e)
{} catch (NumberFormatException e)
{
ShowMessage("数据导入失败,请按照本软件要求的EXCEL格式导入定单");
}
}
public void jButton1_actionPerformed(ActionEvent actionEvent) {
try {
Connection con=conDB();
Statement st = concreateStatement();
ResultSet rs=stexecuteQuery("select NAME,PRICE from test");
StringBuffer sb=null;
定义一个 StringBuffer sb;
sbappend(rsgetString("NAME")+" "+rsgetString("PRICE"))
while(rsnext() )
{
sbappend(rsgetString("NAME")+" "+rsgetString("PRICE"));
jTextAreaappend(sbtoString());
}
rsclose();
stclose();
conclose();
}
catch(Exception e){
JOptionPaneshowMessageDialog(null,"出现异常!");
}
}
java中的JTABLE是采用的MVC设计模式,有几个知识点要了解清楚
1 数据模型:你首先要把数据库中的数据存入数据模型
建立数据模型要实现一个AbstractTableModel接口。接口里有一个类似动态数组的vector变量,将数据库查询的结果存在这个动态的数组(vector)中
例 :public class yourModel extends AbstractTableModel {}
2在JTABLE中调用模型: 在JTABLE组件有个一SETMODEL方法,模型建好后调用这个方法setmodel(model);
先说这么多,网上也有些例子一时没去找,有不明白的再留言
题目有点不清楚。。
什么数据库啊。。
HI我哈。。我帮你看看。。、
给你写了个例子哈
你需要吧jar包引入到项目里面
如果你没有 我传给你哈
import javasqlSQLException;
import javasqlDriverManager;
import javasqlConnection;
import javasqlStatement;
import javasqlPreparedStatement;
import javasqlResultSet;
/
<p>
Title:
</p>
<p>
Description:
</p>
<p>
Copyright: Copyright (c) 2007
</p>
<p>
Company:
</p>
@author not attributable
@version 10
/
public class SQLServer {
Connection con;
String url;//这个是你的数据库url一般是 jdbc:microsoft:sqlserver://
String serverName;//要连的机器 本机就是localhost
String portNumber;//数据库端口 一般是1433
String databaseName;//数据库名字
String userName;//数据库用户名
String password;//数据库密码
String sql;//sql语句
public SQLServer() {
url = "jdbc:microsoft:sqlserver://";
serverName = "localhost";
portNumber = "1433";
databaseName = "mydb";
userName = "sa";
password = "123";
}
String getConnectionUrl() {
return url + serverName + ":" + portNumber + ";databaseName="
+ databaseName + ";";
}
Connection getConnection() {
try {
ClassforName("commicrosoftjdbcsqlserverSQLServerDriver");
con = DriverManagergetConnection(getConnectionUrl(), userName,
password);//这里就是连接数据库 url连起来一般都是 jdbc:microsoft:sqlserver://localhost:1433;databaseName=数据库名;
if (con != null) {
Systemoutprintln("连接成功");
}
} catch (Exception e) {
eprintStackTrace();
}
return con;
}
void display() {
try {
con = getConnection();
sql = "select from student";
PreparedStatement pst = conprepareStatement(sql);
ResultSet rs = pstexecuteQuery();//执行sql语句
while (rsnext()) {
Systemoutprint(rsgetString(1) + "\t");//rsgetString(1) 就是得到第一列
}
} catch (SQLException ce) {
Systemoutprintln(ce);
}
}
public static void main(String[] args) {
SQLServer jdbctest1 = new SQLServer();
jdbctest1display();
}
}
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