2、随机生成几位字符串
3、把这个字符串生成图片
4、将图片随机做一下改颜色、扭曲等操作
5、有服务端传到客户端，客户端填写验证码后传到服务端验证
import java.awt.Colorimport java.awt.Font
import java.awt.Graphics
import java.awt.image.BufferedImage
import java.io.IOException
import java.io.OutputStream
import java.util.Random
import javax.imageio.ImageIO
public class Code {
// 图片的宽度。
private int width = 160
// 图片的高度。
private int height = 38
// 验证码字符个数
private int codeCount = 4
// 验证码干扰线数
private int lineCount = 20
// 验证码
private String code = null
// 验证码图片Buffer
private BufferedImage buffImg = null
Random random = new Random()
private boolean type = false
public Code() {
}
public Code(int width, int height) {
this.width = width
this.height = height
}
public Code(int width, int height, int codeCount) {
this.width = width
this.height = height
this.codeCount = codeCount
}
public Code(int width, int height, int codeCount, int lineCount) {
this.width = width
this.height = height
this.codeCount = codeCount
this.lineCount = lineCount
}
public void init(boolean type){
this.type = type
}
// 生成图片
private void creatImage(boolean type) {
int fontWidth = width / codeCount// 字体的宽度
int fontHeight = height - 5// 字体的高度
int codeY = height - 8
// 图像buffer
buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB)
Graphics g = buffImg.getGraphics()
//Graphics2D g = buffImg.createGraphics()
// 设置背景色
g.setColor(getRandColor(200, 250))
g.fillRect(0, 0, width, height)
// 设置字体
Font font = null
if(!type) font = new Font("Fixedsys", Font.BOLD, fontHeight)
else font = getFont(fontHeight)
g.setFont(font)
// 设置干扰线
for (int i = 0 i < lineCount/2 i++) {
int xs = random.nextInt(width)
int ys = random.nextInt(height)
int xe = xs + random.nextInt(width)
int ye = ys + random.nextInt(height)
g.setColor(getRandColor(1, 255))
if(!type) g.drawLine(xs, ys, xe, ye)
else shear(g, width, height, getRandColor(1, 255))
}
// 添加噪点
float yawpRate = 0.01f// 噪声率
int area = (int) (yawpRate * width * height)
for (int i = 0 i < area i++) {
int x = random.nextInt(width)
int y = random.nextInt(height)
buffImg.setRGB(x, y, random.nextInt(255))
}
String str1 = randomStr(codeCount)// 得到随机字符
this.code = str1
for (int i = 0 i < codeCount i++) {
String strRand = str1.substring(i, i + 1)
g.setColor(getRandColor(1, 255))
// g.drawString(a,x,y)
// a为要画出来的东西，x和y表示要画的东西最左侧字符的基线位于此图形上下文坐标系的 (x, y) 位置处
g.drawString(strRand, i*fontWidth+3, codeY)
}
}
// 得到随机字符
private String randomStr(int n) {
String str1 = "ABCDEFGHJKLMNOPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz1234567890"//I和l不要
String str2 = ""
int len = str1.length() - 1
double r
for (int i = 0 i < n i++) {
r = (Math.random()) * len
str2 = str2 + str1.charAt((int) r)
}
return str2
}
// 得到随机颜色
private Color getRandColor(int fc, int bc) {// 给定范围获得随机颜色
if (fc > 255)
fc = 255
if (bc > 255)
bc = 255
int r = fc + random.nextInt(bc - fc)
int g = fc + random.nextInt(bc - fc)
int b = fc + random.nextInt(bc - fc)
return new Color(r, g, b)
}
/**
* 产生随机字体
*/
private Font getFont(int size) {
Random random = new Random()
Font font[] = new Font[5]
font[0] = new Font("Ravie", Font.PLAIN, size)
font[1] = new Font("Antique Olive Compact", Font.PLAIN, size)
font[2] = new Font("Fixedsys", Font.PLAIN, size)
font[3] = new Font("Wide Latin", Font.PLAIN, size)
font[4] = new Font("Gill Sans Ultra Bold", Font.PLAIN, size)
return font[random.nextInt(5)]
}
// 扭曲方法
private void shear(Graphics g, int w1, int h1, Color color) {
shearX(g, w1, h1, color)
shearY(g, w1, h1, color)
}
private void shearX(Graphics g, int w1, int h1, Color color) {
int period = random.nextInt(2)
boolean borderGap = true
int frames = 1
int phase = random.nextInt(2)
for (int i = 0 i < h1 i++) {
double d = (double) (period >> 1)
* Math.sin((double) i / (double) period
+ (6.2831853071795862D * (double) phase)
/ (double) frames)
g.copyArea(0, i, w1, 1, (int) d, 0)
if (borderGap) {
g.setColor(color)
g.drawLine((int) d, i, 0, i)
g.drawLine((int) d + w1, i, w1, i)
}
}
}
private void shearY(Graphics g, int w1, int h1, Color color) {
int period = random.nextInt(40) + 10 // 50
boolean borderGap = true
int frames = 20
int phase = 7
for (int i = 0 i < w1 i++) {
double d = (double) (period >> 1)
* Math.sin((double) i / (double) period
+ (6.2831853071795862D * (double) phase)
/ (double) frames)
g.copyArea(i, 0, 1, h1, 0, (int) d)
if (borderGap) {
g.setColor(color)
g.drawLine(i, (int) d, i, 0)
g.drawLine(i, (int) d + h1, i, h1)
}
}
}
public void write(OutputStream sos) throws IOException {
if(buffImg == null) creatImage(type)
ImageIO.write(buffImg, "png", sos)
// JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(sos)
// encoder.encode(buffImg)
sos.close()
}
public BufferedImage getBuffImg() {
if(buffImg == null) creatImage(type)
return buffImg
}
public String getCode() {
return code.toLowerCase()
}
//使用方法
/*public void getCode3(HttpServletRequest req, HttpServletResponse response,HttpSession session) throws IOException{
// 设置响应的类型格式为图片格式
response.setContentType("image/jpeg")
//禁止图像缓存。
response.setHeader("Pragma", "no-cache")
response.setHeader("Cache-Control", "no-cache")
response.setDateHeader("Expires", 0)
CreateImageCode vCode = new CreateImageCode(100,30,5,10)
session.setAttribute("code", vCode.getCode())
vCode.write(response.getOutputStream())
response.flushBuffer()
}*/
}
