querytag.java

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package mytag;
import java.io.IOException;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;

import java.sql.*;
import java.io.*;
/**
 * @author  yeeku.H.lee [e-mail]
 * @version  1.0
 * <br>Copyright (C), 2005-2008, yeeku.H.Lee
 * <br>This program is protected by copyright laws.
 * <br>Program Name:
 * <br>Date: 
 */
public class QueryTag extends TagSupport
{
    private String driver;
    private String url;
    private String user;
    private String pass;
    private String sql;

    private Connection conn = null;
    private Statement stmt = null;
    private ResultSet rs = null;
    private ResultSetMetaData rsmd = null;
    
	public void setDriver(String driver) {
		this.driver = driver; 
	}

	public void setUrl(String url) {
		this.url = url; 
	}

	public void setUser(String user) {
		this.user = user; 
	}

	public void setPass(String pass) {
		this.pass = pass; 
	}

	public String getDriver() {
		return (this.driver); 
	}

	public String getUrl() {
		return (this.url); 
	}

	public String getUser() {
		return (this.user); 
	}

	public String getPass() {
		return (this.pass); 
	}

	public String getSql() {
		return (this.sql); 
	}

	public void setSql(String sql) {
		this.sql = sql; 
	}

    public int doEndTag() throws JspTagException
    {
        try
        {
            Class.forName(driver);
            conn = DriverManager.getConnection(url,user,pass);
            stmt = conn.createStatement();
            rs = stmt.executeQuery(sql);
            rsmd = rs.getMetaData();
            int columnCount = rsmd.getColumnCount();
            
            Writer out = pageContext.getOut();
            out.write("<table border='1' bgColor='9999cc'>");
            while (rs.next())
            {
                out.write("<tr>");
                for (int i = 1 ; i <= columnCount ; i++ )
                {
                    out.write("<td>");
                    out.write(rs.getString(i));
                    out.write("</td>");
                }
                out.write("</tr>");
            }
        }
        catch (Exception ex)
        {
            ex.printStackTrace();
            throw new JspTagException("错误");
        }
        return EVAL_PAGE;
    }

    public void destroy()
    {
        if (rs != null)
        try
        {
        	rs.close();
        }
        catch (SQLException sqle)
        {
            sqle.printStackTrace();
        }
        if (stmt != null)
        try
        {
        	stmt.close();
        }
        catch (SQLException sqle)
        {
            sqle.printStackTrace();
        } 
        if (conn != null)
        try
        {
        	conn.close();
        }
        catch (SQLException sqle)
        {
            sqle.printStackTrace();
        } 
    }
}