package net.nyist.exam.web;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 final long serialVersionUID = 1L; 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 doGet(HttpServletRequest request, HttpServletResponse response) {
try {
int charsLength = chars.length(); response.setHeader("ragma", "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(); try {
Thread.sleep(100);
} catch (Exception ex) {
}
OutputStream os = response.getOutputStream();
ImageIO.write(image, "JPEG", os);
os.flush();
os.close();
} catch (Exception ex) { }
}
}
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 final long serialVersionUID = 1L; 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 doGet(HttpServletRequest request, HttpServletResponse response) {
try {
int charsLength = chars.length(); response.setHeader("ragma", "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(); try {
Thread.sleep(100);
} catch (Exception ex) {
}
OutputStream os = response.getOutputStream();
ImageIO.write(image, "JPEG", os);
os.flush();
os.close();
} catch (Exception ex) { }
}
}
package zzq.web.servlet;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 final long serialVersionUID = 1L; 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 doGet(HttpServletRequest request, HttpServletResponse response) {
try {
response.setContentType("image/jpeg");
response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0); int height = 22, width = 60;
BufferedImage bi = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
Graphics gs = bi.getGraphics();
gs.setColor(getRandColor(180, 250));
gs.fillRect(0, 0, width, height);
String base = "abcdefghijklmnopqrstuvwxyz0123456789";
Random rand = new Random();
int size = base.length();
StringBuffer str = new StringBuffer();
gs.setFont(new Font("黑体", Font.BOLD, 19));
for (int i = 0; i < 4; i++) {
int start = rand.nextInt(size);
String tmpStr = base.substring(start, start + 1);
str.append(tmpStr);
gs.setColor(getRandColor(10, 150));
gs.drawString(tmpStr, 13 * i + 6 + rand.nextInt(5), 14 + rand
.nextInt(6));
} String image = new String(str);
request.getSession().setAttribute("validate", image);
OutputStream os = response.getOutputStream();
com.sun.image.codec.jpeg.JPEGImageEncoder en = com.sun.image.codec.jpeg.JPEGCodec
.createJPEGEncoder(os);
en.encode(bi); ImageIO.write(bi, "JPEG", os);
os.flush();
os.close();
} catch (Exception e) {
}
}
}
呵呵,我觉得这个很清晰啦