java+servlet+jsp 将数据库信息回显到页面中

1.在javaBean中首先实例化

private String bmmc ; //实例化部门名称
private String ygjs;  //实例化员工角色

public String getBmmc() {
	return bmmc;
}

public void setBmmc(String bmmc) {
	this.bmmc = bmmc;
}



public String getYgjs() {
	return ygjs;
}

	public void setYgjs(String ygjs) {
		this.ygjs = ygjs;
	}

2.在Dao中写查询方法

//查询部门名称
public List selectBmmc() throws SQLException {
	String sql = "select ID,BM_MC from task_dept";
	conn = getConn();
	stmt = conn.prepareStatement(sql);
	ResultSet rs = stmt.executeQuery(sql);
	List bmmclist= new ArrayList();
	while(rs.next()) {
		Select bmmc = new Select();
		bmmc.setBmid(rs.getInt("ID"));
		bmmc.setBmmc(rs.getString("BM_MC"));
		bmmclist.add(bmmc);
	}
	return bmmclist;
}
//查询员工角色
public List selectygjs() throws SQLException {
	String sql = "select JS_MC from task_role";
	conn = getConn();
	stmt = conn.prepareStatement(sql);
	ResultSet rs = stmt.executeQuery(sql);
	List ygjslist= new ArrayList();
	while(rs.next()) {
		Select ygjs = new Select();
		ygjs.setYgjs(rs.getString(1));
		ygjslist.add(ygjs);
	}
	return ygjslist;
}
	

3.在servlet中调用Dao中的方法

else if(action != null && action.equals("selOne")) {
	int id=Integer.valueOf(request.getParameter("id"));  //得到jsp传过来的ID值
	EmployeeDao employeeDao = new EmployeeDao();
	try {
		List employeeOne = employeeDao.getOne(id);  //调用的查询一条信息的方法
		SelectOptionDao sDao = new SelectOptionDao();
	    	List bmmclist = new ArrayList();
	    	List ygjslist = new ArrayList();
		bmmclist = sDao.selectBmmc();    //调用在Dao中写的方法，查询部门
		ygjslist = sDao.selectygjs();    //调用查询员工角色的方法
         	for(int i = 0;i

4.jsp在前台页面用下拉框的方式显示

    
	  selected>${e.bmmc}