runquerytag.java

JSP学习的好东东

import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import java.io.*;
import java.sql.*;
import java.util.*;

public class RunQueryTag extends BodyTagSupport
{
	public int doStartTag() throws JspException
	{
		System.out.println("RunQueryTag.doStartTag()......");
		return EVAL_PAGE;
	}
	public int doEndTag() throws JspException
	{
		String sql = bodyContent.getString();
		
		if( sql == null){
			throw new JspException("No SQL statement found.");
		}
		sql.trim();
		if(sql.equals("")){
			throw new JspException("Empty SQL statement.");
		}
		ConnectTag ct = (ConnectTag)findAncestorWithClass(this,ConnectTag.class);
		if( ct == null){
			throw new JspException("No ConnectTag Object error.");
		}
		try{
			ct.runQuery( sql );
		}catch(SQLException e){
			throw new JspException( e.getMessage() );
		}
		System.out.println("RunQueryTag.doEndTag()......");
		return EVAL_PAGE;
	}
}