2009-03-16技术学习：Wicket框架下从数据库读取数据

研究了一下Wicket框架中从数据库取数据并显示在表格中，数据库中表（cataLog）有两个字段：CataLogSN，CataInfo，现在使用用JDBC从数据库中取出数据显示了html页面的表格中：

1.连接数据库：

下载mysql-connector-java-5.1.7-bin.jar拷贝至系统环境变量classpath所指的目录下，类代码如下：

import java.sql.*;
public class DBConnect {
private Connection connection;
public DBConnect() {
try {
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/eshop";
this.connection = DriverManager.getConnection(url, "root", "");
} catch (Exception e) {
e.printStackTrace();
}
}
public ResultSet getAll() {
String sql = "SELECT * FROM catalog";
try {
Statement stmt = connection.createStatement();
return stmt.executeQuery(sql);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}

2.建立一个表数据的类：

public class list {
private String log;
private String info;
public list(String log, String info) {
this.log = log;
this.info = info;
}
public String getLog() {
return log;
}
public String getInfo() {
return info;
}

3.建立Wicket页面，DBTest.html主要代码：

<table border="1">
<tr>
<td>CataLog</td>
<td>CataInfo</td>
</tr>
<tr wicket:id="each">
<td wicket:id="log"></td>
<td wicket:id="info"></td>
</tr>
</table>

DBTest.java代码：

import org.apache.wicket.PageParameters;
import org.apache.wicket.markup.html.WebPage;
import org.apache.wicket.markup.html.basic.Label;
import org.apache.wicket.markup.html.list.ListView;
import org.apache.wicket.markup.html.list.ListItem;
import java.util.*;
import java.sql.*;
public final class DBTest extends WebPage {
public DBTest() {
DBConnect conn = new DBConnect();
ResultSet rs = conn.getAll();
List lists = new ArrayList();
try {
while (rs.next()) { //循环获取记录
lists.add(new list(rs.getString("CatalogSN"), rs.getString("CataInfo")));
}
} catch (Exception e) {
e.printStackTrace();
}
ListView each = new ListView("each", lists) {
protected void populateItem(ListItem item) {
list li = (list) item.getModelObject();
item.add(new Label("log", li.getLog()));
item.add(new Label("info", li.getInfo()));
}
};
add(each);
}
}

4.修改Application.java，设置GetHomePage方法：

public Class getHomePage() {
return DBTest.class;
}

5.运行后效果