captchaservlet.java

基于Java平台的、功能强大的验证码图片生成工具

package nl.captcha.servlet;
import java.io.IOException;
import java.util.Enumeration;
import java.util.Properties;

import javax.servlet.Servlet;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import nl.captcha.util.Helper;
import nl.captcha.servlet.CaptchaProducer;

/**
 * @version 	0.1
 * @author		[e-mail]
 */
public class CaptchaServlet extends HttpServlet implements Servlet {
	
	
	private Properties props = null;
	
	private CaptchaProducer captchaProducer = null;

	

	public void doGet(HttpServletRequest req, HttpServletResponse resp)
		throws ServletException, IOException {
			

			
		// this key can be read from any controller to check wether user
		// is a computer or human..
		String capText = captchaProducer.createText();
		req.getSession().setAttribute(Constants.SIMPLE_CAPCHA_SESSION_KEY, capText);
		
		String simpleC =(String) req.getSession().getAttribute(Constants.SIMPLE_CAPCHA_SESSION_KEY);
		
		// notice we don't store the captext in the producer. This is because
		// the thing is not thread safe and we do use the producer as an instance
		// variable in the servlet.
		captchaProducer.createImage(resp.getOutputStream(), capText);

	}

	/* (non-Javadoc)
	 * @see javax.servlet.Servlet#init(javax.servlet.ServletConfig)
	 */
	public void init(ServletConfig conf) throws ServletException {
		super.init(conf);
		// init method should be thread safe so no
		// worries here...
		props = new Properties();
		Enumeration enum = conf.getInitParameterNames();
		while (enum.hasMoreElements()) {
			String key = (String)enum.nextElement();
			String value = conf.getInitParameter(key);
			props.put(key, value);
		}
		
		
		this.captchaProducer = (CaptchaProducer) Helper.ThingFactory.loadImpl(Helper.ThingFactory.CPROD, props);
		
		
		
		
	}
	
 

}