servlet产生验证码的代码
来源:百度文库 编辑:神马文学网 时间:2024/05/26 16:10:00
package com.mapabc.servlet.login;import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.OutputStream;
import java.util.Random;import javax.imageio.ImageIO;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class ImageGenerator extends HttpServlet { private static Color getRandColor(int fc, int bc) {
Random random = new Random();
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);
} private static String charsLong = "23456789abcdefghjklmnpqrstuvwxyzABCDEFGHIJKLMNPQRSTUVWXYZ"; private static String charsShort = "0123456789"; private static String chars = charsLong; @Override
public void service(HttpServletRequest request, HttpServletResponse response) {
try {
int charsLength = chars.length(); response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0); int width = 70, height = 20;
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB); Graphics g = image.getGraphics(); Random random = new Random(); g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height); g.setFont(new Font("Times New Roman", Font.ITALIC, height)); /*g.setColor(getRandColor(160, 200));
for (int i = 0; i < 35; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x, y, x + xl, y + yl);
}*/ StringBuilder sRand = new StringBuilder();
String[] fontNames = { "Times New Roman", "Arial", "Book antiqua",
"" }; for (int i = 0; i < 4; i++) {
g.setFont(new Font(fontNames[random.nextInt(3)], Font.ITALIC,
height));
char rand = chars.charAt(random.nextInt(charsLength));
sRand.append(rand); g.setColor(new Color(20 + random.nextInt(110), 20 + random
.nextInt(110), 20 + random.nextInt(110)));
g.drawString(String.valueOf(rand), 16 * i + random.nextInt(6)
+ 3, height - random.nextInt(4));
} /*g.setColor(getRandColor(160, 200));
for (int i = 0; i < 30; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(width);
int yl = random.nextInt(width);
g.drawLine(x, y, x + xl, y + yl);
}*/ request.getSession().setAttribute("Login_Image_Code",
sRand.toString()); g.dispose(); OutputStream os = response.getOutputStream();
ImageIO.write(image, "JPEG", os);
os.flush();
os.close();
} catch (Exception ex) {
ex.printStackTrace();
// TODO
}
}
}
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.OutputStream;
import java.util.Random;import javax.imageio.ImageIO;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class ImageGenerator extends HttpServlet { private static Color getRandColor(int fc, int bc) {
Random random = new Random();
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);
} private static String charsLong = "23456789abcdefghjklmnpqrstuvwxyzABCDEFGHIJKLMNPQRSTUVWXYZ"; private static String charsShort = "0123456789"; private static String chars = charsLong; @Override
public void service(HttpServletRequest request, HttpServletResponse response) {
try {
int charsLength = chars.length(); response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0); int width = 70, height = 20;
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB); Graphics g = image.getGraphics(); Random random = new Random(); g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height); g.setFont(new Font("Times New Roman", Font.ITALIC, height)); /*g.setColor(getRandColor(160, 200));
for (int i = 0; i < 35; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x, y, x + xl, y + yl);
}*/ StringBuilder sRand = new StringBuilder();
String[] fontNames = { "Times New Roman", "Arial", "Book antiqua",
"" }; for (int i = 0; i < 4; i++) {
g.setFont(new Font(fontNames[random.nextInt(3)], Font.ITALIC,
height));
char rand = chars.charAt(random.nextInt(charsLength));
sRand.append(rand); g.setColor(new Color(20 + random.nextInt(110), 20 + random
.nextInt(110), 20 + random.nextInt(110)));
g.drawString(String.valueOf(rand), 16 * i + random.nextInt(6)
+ 3, height - random.nextInt(4));
} /*g.setColor(getRandColor(160, 200));
for (int i = 0; i < 30; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(width);
int yl = random.nextInt(width);
g.drawLine(x, y, x + xl, y + yl);
}*/ request.getSession().setAttribute("Login_Image_Code",
sRand.toString()); g.dispose(); OutputStream os = response.getOutputStream();
ImageIO.write(image, "JPEG", os);
os.flush();
os.close();
} catch (Exception ex) {
ex.printStackTrace();
// TODO
}
}
}