在注册页面上我们通常需要要做一个图片验证码来防止恶意注册。class="action.accounts.ValidateImageAction">
* Login Page
* @author Michael Zheng 2008-11-18
*/
public class ValidateImageAction {
private InputStream inputStream;
private String randomString; //图片上的字符串
private int length; //图片上字符的个数
private int width; //图片的宽度
private int height; //图片的高度
public String getRandomString() {
if(randomString == null){
randomString =
"$0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
}
return randomString;
}
public void setRandomString(String randomString) {
this.randomString = randomString;
}
public int getLength() {
if(length == 0){
length = 6;
}
return length;
}
public void setLength(int length) {
this.length = length;
}
public int getWidth() {
if(width == 0){
width = 80;
}
return width;
}
public void setWidth(int width) {
this.width = width;
}
public int getHeight() {
if(height == 0){
height = 35;
}
return height;
}
public void setHeight(int height) {
this.height = height;
}
public InputStream getInputStream() {
return inputStream;
}
public void setInputStream(InputStream inputStream) {
this.inputStream = inputStream;
}
public String execute(){
RandomImage validateImage = new RandomImage(getRandomString(),
getLength(), getWidth(), getHeight());
ByteArrayOutputStream bos =new ByteArrayOutputStream();
try {
ImageOutputStream ios = ImageIO.createImageOutputStream(bos);
ImageIO.write(validateImage.getValidateImage(), "JPEG", ios);
inputStream = new ByteArrayInputStream(bos.toByteArray());
bos.close();
} catch (IOException e) {
e.printStackTrace();
}
Map session = ActionContext.getContext().getSession(); //获得
session
session.put("validateString", validateImage.getValidateString
().toLowerCase());
//将验证码转小写放入session
return "success";
}
}
4. function.RandomImage生成图片工厂类
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package function;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.util.Random;
public class RandomImage {
private String validateString; //生成的验证字符串
private BufferedImage validateImage; //生成的验证图片
private String randomString; //图片上的字符串
private int length; //图片上字符的个数
private int width; //图片的宽度
private int height; //图片的高度
public RandomImage(String randomString, int length, int width, int
height){
this.randomString = randomString;
this.length = length;
this.width = width;
this.height = height;
}
//获取生成的验证字符串
public String getValidateString() {
if(validateString==null){
getValidateImage();
}
return validateString;
}
//获取生成的验证图片
public BufferedImage getValidateImage(){
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);// 在内存中创建图象
Graphics2D raphics = (Graphics2D) image.getGraphics();// 获取图形上下
文
raphics.setColor(Color.WHITE);// 设定为白色背景色
raphics.fillRect(0, 0, width, height);
raphics.setFont(new Font("Times New Roman",Font.ITALIC,28));//设
定字体 style:HANGING_BASELINE
raphics.setColor(getRandColor(160,200));//给定范围获得随机颜色
Random random = new Random(); //生成随机类
//随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
for (int i=0;i<255;i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
//int xl = random.nextInt(12);
//int yl = random.nextInt(12);
raphics.drawLine(x,y,x,y);
}
// 取随机产生的认证码(length位数字)
String rand = "";
StringBuffer vString = new StringBuffer();
for (int i=0;i
