jsp自定义标签下拉框

package com.soft.test;

import java.sql.*;

import sun.jdbc.odbc.ee.ConnectionPool;

public class BaseDao {
	//定义数据源驱动
	private static final String drive="oracle.jdbc.driver.OracleDriver";
	//定义连接字符串
	private static final String url="jdbc:oracle:thin:@10.72.240.34:1522:ffv2dev2";
	//用户名
	private static final String uid="produsr";
	//密码
	private static final String pwd="prod_123";
	//获得连接
	public static Connection getConnection()
	{ 
		Connection con=null;
		try {
			//加载驱动
			Class.forName(drive);
			//建立连接
			con=DriverManager.getConnection(url,uid,pwd);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return con;
	}
	//运行有结果，没有参数的sql语句
	public static ResultSet ResultrunSelectSql(String sql)
	{
		Connection con=null;
		PreparedStatement ps=null;
		ResultSet res=null;
		try
		{
	    con=getConnection();
	    ps=con.prepareStatement(sql);
		res=ps.executeQuery();	
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		return res;
	}
	//执行有结果有参数的sql语句
	public static ResultSet runSelectSql(String sql,Object[] params)
	{
		Connection con=null;
		PreparedStatement pre=null;
		ResultSet res=null;
		
		try {
			con=getConnection();
			pre=con.prepareStatement(sql);
		  for(int i=0;i<params.length;i++)
		  {
			  pre.setObject(i+1, params[i]);
			  
		  }
		  res=pre.executeQuery();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return res;
	}
	
	//运行没有结果，没有参数的sql语句
	public static boolean runUpdateSql(String sql)
	
	{
		Connection con=null;
		PreparedStatement ps=null;
		ResultSet res=null;
		try
		{
			con=getConnection();
			ps=con.prepareStatement(sql);
			
		ps.executeUpdate();
		return true;
			
		}
		catch(Exception e)
		{
			e.printStackTrace();
			return false;
		}
		
		
	}
	//执行有结果有参数的sql语句
	public static boolean runUpdateSql(String sql,Object[] params)
	{
		Connection con=null;
		PreparedStatement pre=null;
	
		
		try {
			con=getConnection();
			pre=con.prepareStatement(sql);
		  for(int i=0;i<params.length;i++)
		  {
			  pre.setObject(i+1, params[i]);
			  
		  }
		  pre.executeUpdate();
		  return true;
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return false;
		}	
	}
}
           

package com.soft.test;

import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.TagSupport;

public class MyTag extends TagSupport{
	private String tableName;//表明
	private String label;//下拉框要显示的名称
	private String value;//下拉框的值
	private String where;//条件
	private String selectName;//下拉框的名称
	private String selectId;//下拉款的ID
@Override
public int doEndTag() throws JspException {
	// TODO Auto-generated method stub
	JspWriter out=this.pageContext.getOut();
	String sql="select "+label+","+value+" from "+tableName+" "+where+"";//定义sql语句
	Connection conn=BaseDao.getConnection();
	try {
		PreparedStatement ps=conn.prepareStatement(sql);
		ResultSet res=ps.executeQuery();
		out.print("<select id=\""+selectId+"\" name=\""+selectName+"\">");
		out.print("<option value=\"\">请选择</option>");
	    while(res.next()){
	    	Object values=res.getObject(value);
	    	Object labels=res.getObject(label);
	    	out.print("<option value=\""+values+"\">"+labels+"</option>");
	    }
	    out.print("</select>");
	} catch (SQLException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	} catch (IOException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}finally{
	
	}
	return super.doEndTag();
}
public String getTableName() {
	return tableName;
}
public void setTableName(String tableName) {
	this.tableName = tableName;
}
public String getLabel() {
	return label;
}
public void setLabel(String label) {
	this.label = label;
}
public String getValue() {
	return value;
}
public void setValue(String value) {
	this.value = value;
}
public String getWhere() {
	return where;
}
public void setWhere(String where) {
	this.where = where;
}
public String getSelectName() {
	return selectName;
}
public void setSelectName(String selectName) {
	this.selectName = selectName;
}
public String getSelectId() {
	return selectId;
}
public void setSelectId(String selectId) {
	this.selectId = selectId;
}

}
           

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE taglib PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.2//EN"
                        "http://java.sun.com/dtd/web-jsptaglibrary_1_2.dtd">
<taglib>
 <tlib-version>1.0</tlib-version>
 <jsp-version>1.2</jsp-version>
 <short-name>s</short-name>
 <uri>http://www.574394550.com</uri>
 
 <tag>
 <name>Select</name>
 <tag-class>com.soft.test.MyTag</tag-class>
 <body-content>empty</body-content>
 <attribute>
 <name>tableName</name>
 <required>true</required>
 </attribute>
 
  <attribute>
 <name>label</name>
 <required>true</required>
 </attribute>
 
   <attribute>
 <name>value</name>
 <required>true</required>
 </attribute>
 
  <attribute>
 <name>where</name>
 <required>true</required>
 </attribute>
 
  <attribute>
 <name>selectName</name>
 <required>true</required>
 </attribute>
 
  <attribute>
 <name>selectId</name>
 <required>true</required>
 </attribute>
 </tag>
</taglib>
           

<%@ page language="java"  pageEncoding="gbk"%>
<%@ taglib uri="http://www.574394550.com" prefix="s" %>
<%
String path = request.getContextPath();
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <title>My JSP 'index.jsp' starting page</title>
  </head>
  
  <body>
    This is my JSP page. <br>
    <s:Select selectName="select" selectId="select" label="user_name" value="user_id" tableName="tu_oaf_users" where="where 1=1"/>
  </body>
</html>