java输出扭曲验证码
来源:互联网 发布:淘宝客做爆款 编辑:程序博客网 时间:2024/05/21 17:03
- import java.awt.Color;
- import java.awt.Font;
- import java.awt.Graphics;
- import java.awt.Graphics2D;
- import java.awt.font.FontRenderContext;
- import java.awt.font.TextLayout;
- import java.awt.geom.AffineTransform;
- import java.awt.image.BufferedImage;
- import java.io.IOException;
- import java.text.AttributedString;
- import java.util.Random;
-
- import javax.servlet.ServletException;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
-
- import com.sun.image.codec.jpeg.JPEGCodec;
- import com.sun.image.codec.jpeg.JPEGImageEncoder;
-
-
-
- public class SimpleCaptcha extends HttpServlet {
- private Random generator = new Random();
- private final static String SIMPLE_CAPCHA_SESSION_KEY = "SIMPLE_CAPCHA_SESSION_KEY";
-
- private static char[] captchars = new char[] { 'a', 'b', 'c', 'd', 'e',
- '2', '3', '4', '5', '6', '7', '8', 'g', 'f', 'y', 'n', 'm', 'n',
- 'p', 'w', 'x' };
-
-
-
-
-
-
- private Font getFont() {
- Random random = new Random();
- Font font[] = new Font[5];
- font[0] = new Font("Ravie", Font.PLAIN, 45);
- font[1] = new Font("Antique Olive Compact", Font.PLAIN, 45);
- font[2] = new Font("Forte", Font.PLAIN, 45);
- font[3] = new Font("Wide Latin", Font.PLAIN, 40);
- font[4] = new Font("Gill Sans Ultra Bold", Font.PLAIN, 45);
- return font[random.nextInt(5)];
- }
-
-
-
-
-
-
- private Color getRandColor() {
- Random random = new Random();
- Color color[] = new Color[10];
- color[0] = new Color(32, 158, 25);
- color[1] = new Color(218, 42, 19);
- color[2] = new Color(31, 75, 208);
- return color[random.nextInt(3)];
- }
-
-
-
-
-
-
- public void doGet(HttpServletRequest req, HttpServletResponse resp)
- throws ServletException, IOException {
-
- int ImageWidth = 200;
- int ImageHeight = 100;
-
- int car = captchars.length - 1;
-
-
-
- String test = "";
- for (int i = 0; i < 4; i++) {
- test += captchars[generator.nextInt(car) + 1];
- }
-
-
-
- req.getSession().setAttribute(SimpleCaptcha.SIMPLE_CAPCHA_SESSION_KEY,
- test);
-
-
-
- JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(resp
- .getOutputStream());
-
- BufferedImage bi = new BufferedImage(ImageWidth + 10, ImageHeight,
- BufferedImage.TYPE_BYTE_INDEXED);
-
- Graphics2D graphics = bi.createGraphics();
-
-
-
-
- graphics.setColor(Color.white);
-
- graphics.fillRect(0, 0, bi.getWidth(), bi.getHeight());
-
- graphics.setColor(Color.black);
- AttributedString attstr = new AttributedString(test);
-
- TextLayout textTl = new TextLayout(test, new Font("Courier", Font.BOLD,
- 70), new FontRenderContext(null, true, false));
- AffineTransform textAt = graphics.getTransform();
- graphics.setFont(new Font("Courier", Font.BOLD,70));
- graphics.setColor(this.getRandColor());
- graphics.drawString(test, 10,70);
-
- int w = bi.getWidth();
- int h = bi.getHeight();
- shear(graphics, w, h, Color.white);
-
-
-
- resp.setContentType("image/jpg");
-
- encoder.encode(bi);
-
- }
-
- private void shear(Graphics g, int w1, int h1, Color color) {
-
- shearX(g, w1, h1, color);
- shearY(g, w1, h1, color);
- }
-
- public void shearX(Graphics g, int w1, int h1, Color color) {
-
- int period = generator.nextInt(2);
-
- boolean borderGap = true;
- int frames = 1;
- int phase = generator.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);
- }
- }
-
- }
-
- public void shearY(Graphics g, int w1, int h1, Color color) {
-
- int period = generator.nextInt(40) + 10;
-
- 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);
- }
-
- }
-
- }
-
- private void drawThickLine(Graphics g, int x1, int y1, int x2, int y2,
- int thickness, Color c) {
-
-
- g.setColor(c);
- int dX = x2 - x1;
- int dY = y2 - y1;
-
- double lineLength = Math.sqrt(dX * dX + dY * dY);
-
- double scale = (double) (thickness) / (2 * lineLength);
-
-
-
- double ddx = -scale * (double) dY;
- double ddy = scale * (double) dX;
- ddx += (ddx > 0) ? 0.5 : -0.5;
- ddy += (ddy > 0) ? 0.5 : -0.5;
- int dx = (int) ddx;
- int dy = (int) ddy;
-
-
- int xPoints[] = new int[4];
- int yPoints[] = new int[4];
-
- xPoints[0] = x1 + dx;
- yPoints[0] = y1 + dy;
- xPoints[1] = x1 - dx;
- yPoints[1] = y1 - dy;
- xPoints[2] = x2 - dx;
- yPoints[2] = y2 - dy;
- xPoints[3] = x2 + dx;
- yPoints[3] = y2 + dy;
-
- g.fillPolygon(xPoints, yPoints, 4);
- }
-
- }