java验证码工具类（自己编写的，仅供参考）

package com.chenb.test;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.swing.ButtonGroup;

public class VerifyCodeUtils {
//验证码
private String codeText;
//验证码的宽（默认110）
private Integer codeImgWidth;
//验证码图片的高（默认25）
private Integer codeImgHeight;
//验证码的个数（默认4）
private Integer codeSize;
//验证码的字体大小
private Integer fontSize;
//干扰线的条数(默认为5)
private Integer lineSize;
//干扰线的透明度(100)alpha 值为 255 则意味着颜色完全是不透明的，alpha 值为 0意味着颜色是完全透明的
private Integer lineAlpha;
//噪点(干扰点)的个数
private Integer randomPointSize;
//背景色
private Color backgroundColor;
//纯数字验证码
private final static Integer MODE_FULL_NUMBER=1;
//纯字母验证码
private final static Integer MODE_FULL_CHAR=2;
//数字和字母组合验证码
private final  static Integer MODE_NUMBER_AND_CHAE=3;
//验证码的类型
private  Integer modeType;
//验证码图片
private  BufferedImage codeImage;

//构造方法
public VerifyCodeUtils(Integer codeImgWidth,Integer codeImgHeight,Integer codeSize,Integer fontSize,Integer lineSize,Integer lineAlpha,Integer randomPointSize,Color backgroundColor,Integer modeType){
this.codeImgHeight=codeImgWidth;
this.codeImgHeight=codeImgHeight;
this.codeSize=codeSize;
this.fontSize=fontSize;
this.lineSize=lineSize;
this.lineAlpha=lineAlpha;
this.randomPointSize=randomPointSize;
this.backgroundColor=backgroundColor;
this.modeType=modeType;
this.codeImage=createCodeImage();
}
//构造方法
public VerifyCodeUtils(Integer codeImgWidth,Integer codeImgHeight,Integer codeSize,Integer fontSize,Integer lineSize,Integer lineAlpha,Integer randomPointSize,Color backgroundColor){
this(codeImgWidth,codeImgHeight,codeSize,fontSize,lineSize,lineAlpha,randomPointSize,backgroundColor,null);
}
public VerifyCodeUtils(Integer codeImgWidth,Integer codeImgHeight,Integer codeSize,Integer fontSize,Integer lineSize,Integer lineAlpha,Integer randomPointSize){
this(codeImgWidth,codeImgHeight,codeSize,fontSize,lineSize,lineAlpha,randomPointSize,null);
}
public VerifyCodeUtils(Integer codeImgWidth,Integer codeImgHeight,Integer codeSize,Integer fontSize,Integer lineSize,Integer lineAlpha){
this(codeImgWidth,codeImgHeight,codeSize,fontSize,lineSize,lineAlpha,null);
}
public VerifyCodeUtils(Integer codeImgWidth,Integer codeImgHeight,Integer codeSize,Integer fontSize,Integer lineSize){
this(codeImgWidth,codeImgHeight,codeSize,fontSize,lineSize,null);
}
public VerifyCodeUtils(Integer codeImgWidth,Integer codeImgHeight,Integer codeSize,Integer fontSize){
this(codeImgWidth,codeImgHeight,codeSize,fontSize,null);
}
public VerifyCodeUtils(Integer codeImgWidth,Integer codeImgHeight,Integer codeSize){
this(codeImgWidth,codeImgHeight,codeSize,null);
}
public VerifyCodeUtils(Integer codeImgWidth,Integer codeImgHeight){
this(codeImgWidth,codeImgHeight,null);
}
public VerifyCodeUtils(){
this(null,null);
}

//生成0~9随机数
private Integer getRandomNumber(){
Random random=new Random();
return random.nextInt(10);
}
//生成a-z和A-Z随机字符
private char getRandomChar() {
Random random=new Random();
int randomNum=random.nextInt(26);
int Lower_Or_UpperCase=random.nextInt(2);
if(Lower_Or_UpperCase==0){
return (char)(randomNum+65);
}
return (char)(randomNum+97);
}
//生成随机颜色 alpha 值为 255 则意味着颜色完全是不透明的，alpha 值为 0意味着颜色是完全透明的
private Color getRandomColor(Integer alpha){
Random random=new Random();
int red=random.nextInt(150);
int green=random.nextInt(150);
int blue=random.nextInt(150);
if(alpha==null){
alpha=255;
}
return new Color(red,green,blue,alpha);
}
//创建BufferImage
private BufferedImage createBufferedImage(){
if(this.codeImgWidth==null){
this.codeImgWidth=110;
}
if(this.codeImgHeight==null){
this.codeImgHeight=25;
}
BufferedImage bufferedImage=new BufferedImage(this.codeImgWidth,this.codeImgHeight,BufferedImage.TYPE_INT_RGB);
Graphics2D graphics2D=(Graphics2D)bufferedImage.getGraphics();
if(this.backgroundColor==null){
backgroundColor=new Color(255,255,255);
}
graphics2D.setBackground(this.backgroundColor);
graphics2D.fillRect(0,0,codeImgWidth,codeImgHeight);
return bufferedImage;
}
//画干扰线
private BufferedImage drawLine(BufferedImage bufferedImage){
Random random=new Random();
if(this.lineSize==null){
lineSize=5;
}
Graphics2D graphics2D=(Graphics2D)bufferedImage.getGraphics();
for(int i=0;i<lineSize;i++){
//直线起点的x坐标
int startX=random.nextInt(bufferedImage.getWidth()-1);
//直线起点的y坐标
int startY=random.nextInt(bufferedImage.getHeight()-1);
//直线结束点的x坐标
int endX=random.nextInt(bufferedImage.getWidth()-1);
//直线结束点的y坐标
int endY=random.nextInt(bufferedImage.getHeight()-1);
if(this.lineAlpha==null){
this.lineAlpha=100;
}
//直线的颜色
graphics2D.setColor(getRandomColor(lineAlpha));
// 处理干扰线与边框的交界（1f为线条的宽度）
graphics2D.setStroke(new BasicStroke(1f));
graphics2D.drawLine(startX,startY,endX,endY);
}
return bufferedImage;
}
//添加噪声点
//画干扰线
private BufferedImage drawRandomPoint(BufferedImage bufferedImage){
Random random=new Random();
if(this.randomPointSize==null){
randomPointSize=20;
}
for(int i=0;i<randomPointSize;i++){
int x=random.nextInt(bufferedImage.getWidth()-1);
int y=random.nextInt(bufferedImage.getHeight()-1);
int rgb=getRandomColor(100).getRGB();
bufferedImage.setRGB(x, y, rgb);
}
return bufferedImage;
}
//根据模式生成验证码字符
private String careateCode(){
String result="";
if(this.modeType==null){
this.modeType=MODE_NUMBER_AND_CHAE;
}
if(modeType==MODE_FULL_NUMBER){
result=getRandomNumber()+"";
}
if(modeType==MODE_FULL_CHAR){
result=getRandomChar()+"";
}
if(modeType==MODE_NUMBER_AND_CHAE){
Random random=new Random();
int randomChoseNum=random.nextInt(2);
if(randomChoseNum==0){
result=getRandomNumber()+"";
}else{
result=getRandomChar()+"";
}
}
return result;
}
//得到验证码
public String getCodeText(){
return this.codeText;
}

//输出验证码到HttpResponse
public void writeOut(OutputStream os){
try{
ImageIO.write(this.codeImage,"PNG",os);
}catch (Exception e){
e.printStackTrace();
}
}
//输出验证码图片BufferedImage
public BufferedImage getBufferedImage(){
return this.codeImage;
}
//设置字体
private Font getFont() {
if(this.fontSize==null){
fontSize=19;
}
return new Font("Fixedsys", Font.CENTER_BASELINE, fontSize);
}
//生成验证码图片
private BufferedImage createCodeImage(){
BufferedImage image = createBufferedImage();//创建图片缓冲区
image=drawLine(image);
image=drawRandomPoint(image);
Graphics2D g2 = (Graphics2D)image.getGraphics();//得到绘制环境
g2.setStroke(new BasicStroke(1.5f));
g2.setFont(getFont());
if(this.codeSize==null){
this.codeSize=4;
}
//用来装验证码
StringBuilder sb=new StringBuilder();
for(int i=0;i<codeSize;i++) {
g2.setColor(getRandomColor(null));
String codeChar=careateCode();
sb.append(codeChar);
//平移或旋转变换
Random random=new Random(System.nanoTime());
AffineTransform affine = new AffineTransform();
affine.setToRotation(Math.PI / 4 * random.nextDouble() * (random.nextBoolean() ? 1 : -1), (codeImgWidth/ codeSize) * i + 18/2, codeImgHeight/2);
g2.setTransform(affine);
// 首字符的基线位于用户空间中的 (x,y) 位置处
g2.drawString(codeChar, 6 + i * (codeImgWidth/codeSize), Math.round(codeImgHeight*0.8));
}
this.codeText=sb.toString();//验证码文本
return image;
}
public static void main(String[] args) throws FileNotFoundException {
VerifyCodeUtils verifyCodeUtils = new VerifyCodeUtils(200,40,null,25);
//验证码
String verifyCode=verifyCodeUtils.getCodeText();
//本地测试输出到桌面，保存为图片（在项目中使用response.getOutputStream()）
OutputStream oStream=new FileOutputStream(new File("C:\\Users\\hasee\\Desktop","verifyCodeImg.jpg"));
verifyCodeUtils.writeOut(oStream);
System.out.println("验证码为:"+verifyCode);
}
}