dbconnection.java

数据库连接类。无需在每个类或者JSP文件里都写连接数据库的代码

package util;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DBConnection{
    private static String driverName="com.microsoft.jdbc.sqlserver.SQLServerDriver";
	private static String url="jdbc:sqlserver://localhost:1433:DataBaseName=jdbc_text";
	private static String user="sa";
	private static String password="";
	private DBConnection(){
	}
	static{
	     try{
		     Class.forName(driverName);
		 }catch(ClassNotFoundException e){
		     e.printStackTrace();
			 throw new ExceptionInInitializerError(e.getMessage());
		 }
	}
    public static Connection getConnection() throws SQLException{
	   return DriverManager.getConnection(url,user,password);
	}
	public static void close(ResultSet rs,Statement st,Connection conn){
	  try{
	      if(rs!=null){rs.close();}
	  }catch(SQLException e){
	     e.printStackTrace();
	  }finally{
	      try{
		       if(st!=null){st.close();}
		  }catch(SQLException e){
		      e.printStackTrace();
		  }finally{
		          if(conn!=null){
				        try{
						      conn.close();
							  }catch(SQLException e){
							     e.printStackTrace();
							  }
				  }
		  }
	  }
	}
public static void main(String []arg) throws SQLException{
    Connection conn=null;
  Statement st=null;
  ResultSet rs=null;
  try{
  conn=DBConnection.getConnection();
  String sql="insert into [user](name,password,email,age,birthday,money)"
         +
  "values('zhangsan','123','[e-mail]',21,'1988-1-24',500.0)";
  st=conn.createStatement();
  st.executeUpdate(sql);
  }finally{
  DBConnection.close(rs,st,conn);
}     
}
}