java代码完成验证码的生成

package cn.com.lx;

import java.awt.BasicStroke;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics2D;

import java.awt.image.BufferedImage;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.util.Random;

import javax.imageio.ImageIO;

import org.junit.Test;

public class Image {

    private int w=70;

    private int h=35;

private Random r=new Random();

    //1.RGB颜色

private Color col=new Color(255, 255, 255);//三个值要在这个区间内，怎么变成了都是255不就是一个颜色了么？

public Color setC(){

int red=r.nextInt(155);

int green=r.nextInt(155);

int blue=r.nextInt(155);

Color color=new Color(red,green,blue);

return color;    

}

//2.字体

public Font setF(){

//字体形式，大小，楷书等

int size=r.nextInt(4)+25;

int style=r.nextInt(4);

String [] string ={"宋体","楷体"};

int index=r.nextInt(string.length);

String name=string[index];

Font font=new Font(name,style,size);

return font;    

}

//3.字符

public char setCh(){

    String chars="1234567890qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBVNM";

    int index=r.nextInt(chars.length());

    char ch=chars.charAt(index);

    return ch;

}

//4.干扰线

public void DrawLine(BufferedImage bff){

 

Graphics2D gh=(Graphics2D) bff.getGraphics();

    for (int i = 0; i <3; i++) {

        //1.三条干扰线

        int x1=r.nextInt(w);

        int x2=r.nextInt(w);

        int y1=r.nextInt(h);

        int y2=r.nextInt(h);

        gh.setStroke(new BasicStroke(1.5F));

        gh.setColor(Color.blue);

        gh.drawLine(x1, y1, x2, y2);

    }

}

public BufferedImage bff(){

    //1.缓存区    

    BufferedImage img=new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);

    //2.设置颜色以及前期准备

    Graphics2D gh2=(Graphics2D) img.getGraphics();

    gh2.setColor(col);    

    gh2.fillRect(0, 0, w, h);

    return img;

}

//5.开始绘制

@Test

public void draw() throws FileNotFoundException, IOException{

BufferedImage img=bff();

Graphics2D gh2=(Graphics2D) img.getGraphics();

//StringBuilder sb=new StringBuilder();

//3.图形绘制

for (int i = 0; i <4; i++) {

    gh2.setFont(setF());

    gh2.setColor(setC());

    String c=setCh()+"";

  //  sb.append(c);

    float x=i*1.0F*w/4;

    

    gh2.drawString(c, x, h-5);

}

//4.添加干扰线

DrawLine(img);

ImageIO.write(img, "JPEG", new FileOutputStream("D:/g.jpg"));

}

}