java 验证码 背景

java 验证码 背景

不说什么，代码能为我解释。透明的背景重要的一点就是只能在于png格式，而不是jpg格式。

package b.yzmcode.web;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.image.BufferedImage;

import java.io.IOException;

import java.util.Random;

import javax.imageio.ImageIO;

import org.vention.annotation.Action;

import org.springframework.stereotype.Controller;

import com.shengdai.base.support.struts.BaseStrutsAction;

@Controller

public class YzmCodeAction extends BaseStrutsAction{

/**

*

*/

private static final long serialVersionUID = 1L;

private static final int WIDTH=120;

private static final int HEIGHT = 30;

public YzmCodeAction() {

super();

}

@Action

public void validate() {

BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_ARGB);

Graphics2D g = ateGraphics();

//1.设置背景颜色

setBackground(g);

//2.设置边框

setBorder(g);

//3.画干扰线

drawRandomLine(g);

//4.生成随机数

String codes = drawRandomNum((Graphics2D)g);