Java 验证码
生成验证码
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
import org.springframework.stereotype.Component;
/**
* CheckCode.java
*
* @author King<br/>
*
* @Description 验证码生成类
* @since 1.0.0
* @Date 2012-2-29下午1:50:25
*/
@Component
public class CheckCode {
private int width = 102;
private int height = 28;
private int codeCount = 4;
private Random random = new Random();
/**
* 验证码图片
*/
private BufferedImage buffImg;
/**
* 验证码字符串
*/
private String checkCodeStr;
/**
*
* @Description:创建验证码对象
* @since 1.0.0
* @Date:2012-3-1 上午10:26:20
* @return CheckCode
*/
public CheckCode createCheckCode() {
CheckCode checkCode = new CheckCode();
checkCode.setCheckCodeStr(createRandomCode());
checkCode.setBuffImg(disturb());
return checkCode;
}
/**
*
* @Description:随机产生的验证码
* @since 1.0.0
* @Date:2012-3-1 上午10:20:05
* @return String
*/
private String createRandomCode() {
StringBuffer randomCode = new StringBuffer();
String strRand = null;
int xx = width / (codeCount + 1);
int codeY = height - 4;
char[] codeSequence = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J',
'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
'X', 'Y', 'Z', '2', '3', '4', '5', '6', '7', '8', '9' };
Graphics2D graphics = graphicsInit();
graphics.setColor(createColor());
for (int i = 0; i < codeCount; i++) {
strRand = String.valueOf(codeSequence[random.nextInt(32)]);
randomCode.append(strRand);
graphics.drawString(strRand, (i + 1) * xx, codeY);
}
return randomCode.toString();
}
/**
*
* @Description:创建颜色
* @since 1.0.0
* @Date:2012-2-29 下午4:47:14
* @return Color
*/
private Color createColor() {
Color color[] = new Color[10];
color[0] = new Color(113, 31, 71);
color[1] = new Color(37, 0, 37);
color[2] = new Color(111, 33, 36);
color[3] = new Color(0, 0, 112);
color[4] = new Color(14, 51, 16);
color[5] = new Color(1, 1, 1);
color[6] = new Color(72, 14, 73);
color[7] = new Color(65, 67, 29);
color[8] = new Color(116, 86, 88);
color[9] = new Color(41, 75, 71);
return color[random.nextInt(10)];
}
/**
*
* @Description:绘制类初始化
* @since 1.0.0
* @Date:2012-3-1 上午10:17:52
* @return Graphics2D
*/
private Graphics2D graphicsInit() {
Graphics2D graphics = buffImgInit().createGraphics();
graphics.setColor(Color.WHITE);
graphics.fillRect(0, 0, width, height);
graphics.setFont(new Font("Fixedsys", Font.BOLD, height - 2));
graphics.drawRect(0, 0, width - 1, height - 1);
return graphics;
}
/**
*
* @Description:BufferedImage初始化
* @since 1.0.0
* @Date:2012-3-1 上午11:07:18
* @return BufferedImage
*/
private BufferedImage buffImgInit() {
buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
return buffImg;
}
/**
*
* @Description:绘制干扰特性
* @since 1.0.0
* @Date:2012-3-1 上午11:45:32
* @return BufferedImage
*/
private BufferedImage disturb() {
drawDisturbLine(buffImg.createGraphics());
return twistImage();
}
/**
*
* @Description:画干扰线使图象中的认证码不易被其它程序探测到
* @since 1.0.0
* @Date:2012-2-29 下午4:28:23
* @param graphics
* void
*/
private void drawDisturbLine(Graphics2D graphics) {
graphics.setColor(Color.BLACK);
int x = 0;
int y = 0;
int xl = 0;
int yl = 0;
for (int i = 0; i < 15; i++) {
x = random.nextInt(width);
y = random.nextInt(height);
xl = random.nextInt(20);
yl = random.nextInt(10);
graphics.drawLine(x, y, x + xl, y + yl);
}
}
/**
*
* @Description:正弦曲线Wave扭曲图片
* @since 1.0.0
* @Date:2012-3-1 下午12:49:47
* @return BufferedImage
*/
private BufferedImage twistImage() {
double dMultValue = random.nextInt(7) + 3;// 波形的幅度倍数，越大扭曲的程序越高，一般为3
double dPhase = random.nextInt(6);// 波形的起始相位，取值区间（0-2＊PI）
BufferedImage destBi = new BufferedImage(buffImg.getWidth(),
buffImg.getHeight(), BufferedImage.TYPE_INT_RGB);
for (int i = 0; i < destBi.getWidth(); i++) {
for (int j = 0; j < destBi.getHeight(); j++) {
int nOldX = getXPosition4Twist(dPhase, dMultValue,
destBi.getHeight(), i, j);
int nOldY = j;
if (nOldX >= 0 && nOldX < destBi.getWidth() && nOldY >= 0
&& nOldY < destBi.getHeight()) {
destBi.setRGB(nOldX, nOldY, buffImg.getRGB(i, j));
}
}
}
return destBi;
}
/**
*
* @Description:获取扭曲后的x轴位置
* @since 1.0.0
* @Date:2012-3-1 下午3:17:53
* @param dPhase
* @param dMultValue
* @param height
* @param xPosition
* @param yPosition
* @return int
*/
private int getXPosition4Twist(double dPhase, double dMultValue,
int height, int xPosition, int yPosition) {
double PI = 3.1415926535897932384626433832799; // 此值越大，扭曲程度越大
double dx = (double) (PI * yPosition) / height + dPhase;
double dy = Math.sin(dx);
return xPosition + (int) (dy * dMultValue);
}
/**
*
* @Description:将图像进行输出到文件
* @since 1.0.0
* @Date:2012-3-1 上午11:56:19
* @param pathName
* @return String
*/
public String createImgFile(String pathName) {
File file = new File(pathName);
if (file.isFile() && file.exists()) {
file.delete();
}
try {
ImageIO.write(buffImg, "jpeg", file);
} catch (IOException e) {
e.printStackTrace();
}
return pathName;
}
public BufferedImage getBuffImg() {
return buffImg;
}
public void setBuffImg(BufferedImage buffImg) {
this.buffImg = buffImg;
}
public String getCheckCodeStr() {
return checkCodeStr;
}
public void setCheckCodeStr(String checkCodeStr) {
this.checkCodeStr = checkCodeStr;
}
public int getWidth() {
return width;
}
public void setWidth(int width) {
this.width = width;
}
public int getHeight() {
return height;
}
public void setHeight(int height) {
this.height = height;
}
public int getCodeCount() {
return codeCount;
}
public void setCodeCount(int codeCount) {
this.codeCount = codeCount;
}
}
测试：
import org.junit.Assert;
import org.junit.Test;
/**
* CheckCodeTest.java
* @author King<br/>
*
* @Description 描述一下这个文件
* @since 1.0.0
* @Date 2012-2-29下午1:51:13
*/
public class CheckCodeTest {
@Test
public void testCheckCodeCreate(){
CheckCode checkCode=new CheckCode();
checkCode=checkCode.createCheckCode();
String checkCodeStr=checkCode.getCheckCodeStr();
System.out.println(checkCodeStr);
Assert.assertNotNull(checkCodeStr);
Assert.assertEquals(4, checkCodeStr.length());
Assert.assertNotNull(checkCode.getBuffImg());
// for (int i = 0; i < 10; i++) {
// checkCode=checkCode.createCheckCode();
// String checkCodeStr=checkCode.getCheckCodeStr();
// System.out.println(checkCodeStr);
// Assert.assertNotNull(checkCodeStr);
// Assert.assertEquals(4, checkCodeStr.length());
//
// String filePathName="C:\\test"+i+".jpg";
// checkCode.createImgFile(filePathName);
// File file=new File(filePathName);
//
// Assert.assertTrue(file.exists());
// }
}
}
第三方库kaptcha 实现验证码
kaptcha的作者很反感maven，他们不信任中央库。所以不支持maven。要自己搞maven包。
官网：https://code.google.com/p/kaptcha/
依赖：
<dependency> <groupId>com.jhlabs</groupId> <artifactId>filters</artifactId> <version>2.0.235-1</version> </dependency>
kaptcha需要使用classifier指定JDK版本：
<dependency> <groupId>com.google.code.kaptcha</groupId> <artifactId>kaptcha</artifactId> <version>2.3</version> <classifier>jdk15</classifier> </dependency>
DefaultKaptcha productor = new DefaultKaptcha();
productor.setConfig(new Config(new Properties()));
BufferedImage image = productor.createImage("Hello World");
ByteArrayOutputStream out = new ByteArrayOutputStream();
ImageIO.write(image, "jpg", out);
byte[] imageData = out.toByteArray();
File imageFile = new File(this.imgTag + "kaptcha.jpg");
OutputStream os = null;
try {
os = new FileOutputStream(imageFile);
os.write(imageData);
} catch (Exception e) {
throw e;
} finally {
if (null != os) {
os.close();
}
}
配置参数
Configuration is done through web.xml. All values can be left blank and a default value will be chosen.
Below is an example of the init-param you would add to your web.xml. If you want to set other variables, then you would add more init-param blocks.
<init-param>
<param-name>kaptcha.border</param-name>
<param-value>yes</param-value>
</init-param>
Note: This only works with the KaptchaServlet. SimpleServlet does not pay attention to the web.xml parameters.
Details
These values are stored in the com.google.code.kaptcha.Constants class.
| Constant | Description | Default |
|---|---|---|
| kaptcha.border | Border around kaptcha. Legal values are yes or no. | yes |
| kaptcha.border.color | Color of the border. Legal values are r,g,b (and optional alpha) or white,black,blue. | black |
| kaptcha.border.thickness | Thickness of the border around kaptcha. Legal values are > 0. | 1 |
| kaptcha.image.width | Width in pixels of the kaptcha image. | 200 |
| kaptcha.image.height | Height in pixels of the kaptcha image. | 50 |
| kaptcha.producer.impl | The image producer. | com.google.code.kaptcha.impl.DefaultKaptcha |
| kaptcha.textproducer.impl | The text producer. | com.google.code.kaptcha.text.impl.DefaultTextCreator |
| kaptcha.textproducer.char.string | The characters that will create the kaptcha. | abcde2345678gfynmnpwx |
| kaptcha.textproducer.char.length | The number of characters to display. | 5 |
| kaptcha.textproducer.font.names | A list of comma separated font names | Arial, Courier |
| kaptcha.textproducer.font.size | The size of the font to use. | 40px. |
| kaptcha.textproducer.font.color | The color to use for the font. Legal values are r,g,b. | black |
| kaptcha.textproducer.char.space | The space between the characters | 2 |
| kaptcha.noise.impl | The noise producer. | com.google.code.kaptcha.impl.DefaultNoise |
| kaptcha.noise.color | The noise color. Legal values are r,g,b. | black |
| kaptcha.obscurificator.impl | The obscurificator implementation. | com.google.code.kaptcha.impl.WaterRipple |
| kaptcha.background.impl | The background implementation. | com.google.code.kaptcha.impl.DefaultBackground |
| kaptcha.background.clear.from | Starting background color. Legal values are r,g,b. | light grey |
| kaptcha.background.clear.to | Ending background color. Legal values are r,g,b. | white |
| kaptcha.word.impl | The word renderer implementation. | com.google.code.kaptcha.text.impl.DefaultWordRenderer |
| kaptcha.session.key | The value for the kaptcha is generated and is put into the HttpSession. This is the key value for that item in the session. | KAPTCHA_SESSION_KEY |
| kaptcha.session.date | The date the kaptcha is generated is put into the HttpSession. This is the key value for that item in the session. | KAPTCHA_SESSION_DATE |