Java Tools Class--Verification code (VERIFYCODE)

import java.awt.BasicStroke; import java.awt.Color; import Java.awt.Font; import
Java.awt.Graphics2D;
Import Java.awt.image.BufferedImage;
Import java.io.FileNotFoundException;
Import java.io.IOException;
Import Java.io.OutputStream;

Import Java.util.Random;

Import Javax.imageio.ImageIO; public class Verifycode {

	private int w = 70;

	private int h = 35;
	Private Random R = new Random ();
	Definition has those fonts private string[] FontNames = {"XXFarEastFont-Arial", "XXFarEastFont-Arial", "Boldface", "Microsoft Ya-hei", "italics _gb2312"};
	Define random characters with those captcha code private String codes = "23456789abcdefghjkmnopqrstuvwxyzABCDEFGHJKLMNOPQRSTUVWXYZ";
	Generate background color private color bgcolor = new color (250, 250, 250);

	Used for the GetText method to obtain the generated CAPTCHA text private String text;
		Generate random color private color randomcolor () {int red = R.nextint (150);
		int green = R.nextint (150);
		int blue = R.nextint (150);
	return new Color (red, green, blue);
		//Generate random Font private font randomfont () {int index = R.nextint (fontnames.length);
		String fontname = Fontnames[index];
		int style = R.nextint (4);

		int size = R.nextint (5) + 24;
	return new Font (FontName, style, size);
		///Draw interference line private void DrawLine (bufferedimage image) {int num = 3;
		graphics2d g2 = (graphics2d) image.getgraphics ();
			for (int i = 0; i < num i++) {int x1 = r.nextint (w);
			int y1 = R.nextint (h); int x2= R.nextint (w);
			int y2 = r.nextint (h);
			G2.setstroke (New Basicstroke (1.5F));/Do not know G2.setcolor (Color.Blue);
		G2.drawline (x1, y1, x2, y2); }///Get the random number within the length of the codes and use Charat to get the character of the codes in the random number position private char Randomchar () {int index = R.nextint (Codes.length ()
		);
	Return Codes.charat (index); //Create a CAPTCHA picture public bufferedimage createimage () {bufferedimage image = new BufferedImage (W, H, BufferedImage.)
		TYPE_INT_RGB);
		graphics2d g2 = (graphics2d) image.getgraphics ();
		StringBuilder sb = new StringBuilder ();
			Draw four characters for (int i = 0; i < 4; i++) {String s = Randomchar () + "";
			Sb.append (s);
			float x = i * 1.0F * W/4;
			G2.setfont (Randomfont ());
			G2.setcolor (Randomcolor ());

		G2.drawstring (S, x, h-5);
		} This.text = Sb.tostring ();

		DrawLine (image);

	Returns the picture return image;
	///Get the verification code of the text is used to check with the user input authentication code with public String GetText () {return text; }//Define output object and direction of output public static void output (BufferedImage bi, OutputStream fos) throws FileNotFoundException, IOException {imageio.write (bi, "JPEG", FOS); }
}

Above, a verification code is generated.

Write a test to generate the specified captcha image jpg

public class Test {public
	static void Main (string[] args) throws IOException {
		Verifycode code = new Verifycode () ;
		BufferedImage image = Code.createimage ();
		Imageio.write (image, "JPG", New File ("f:/image.jpg"));
	}

Of course, it can also be generated in the servlet.

@WebServlet (urlpatterns= "/verifycodeservlet.do") public
class Verifycodeservlet extends HttpServlet {

	@ Override
	protected Void Service (HttpServletRequest request, httpservletresponse response)
			throws Servletexception, IOException {
		Verifycode code = new Verifycode ();
		BufferedImage image = Code.createimage ();
		Imageio.write (image, "JPG", Response.getoutputstream ());
	}

And then show it in. html or. jsp