Java中的BaseDao怎么用？

你好，我写的BaseDao:

package dao

import java.sql.*

/**

*

* @author Administrator

*数据库连接

*/

public class BaseDao {

//连接字符串

public String driver="oracle.jdbc.driver.OracleDriver"//数据库驱动

public String url="jdbc:oracle:thin:@localhost:1521:hfaccp"//建立到给定数据库 URL 的连接。

public String username="system"//数据库用户

public String password="system"//数据库密码

//声明接口

public Connection con

public PreparedStatement pstmt

public ResultSet rs

//获得数据库连接

public Connection getConnection()

{

try {

Class.forName(driver)

con=DriverManager.getConnection(url,username,password)

} catch (ClassNotFoundException e) {

e.printStackTrace()

} catch (SQLException e) {

e.printStackTrace()

}

return con

}

//释放数据库资源

public void CloseAll()

{

if(rs!=null)

{

try {

rs.close()

} catch (SQLException e) {

e.printStackTrace()

}

}

if(pstmt!=null)

{

try {

pstmt.close()

} catch (SQLException e) {

e.printStackTrace()

}

}

if(con!=null)

{

try {

con.close()

} catch (SQLException e) {

e.printStackTrace()

}

}

}

}

public static int executeSQL(String preparedSql, Object[] param) {

Connection conn = null

PreparedStatement pstmt = null

int num = 0

try {

conn = getConnectionForJndi()

pstmt = conn.prepareStatement(preparedSql)

if (param != null) {

for (int i = 0i <param.lengthi++) {

pstmt.setObject(i + 1, param[i])

}

num = pstmt.executeUpdate()

}

} catch (SQLException e) {

e.printStackTrace()

} catch (DBAccessException e) {

e.printStackTrace()

} finally {

closeAll(conn, pstmt, null)//释放资源

}

return num

}

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