Java implementation Verification Code specific code (pictures, Chinese characters) _java

This article for everyone to share two examples, I believe you will love.

Example 1: Randomly generating a captcha picture and outputting it as a PNG file

Effect Chart:

Import Java.awt.Color;
Import Java.awt.Font;
Import Java.awt.Graphics;
Import Java.awt.image.BufferedImage;
Import Java.io.File;
Import java.io.IOException;
 
Import Java.util.Random;
 
Import Javax.imageio.ImageIO;
  public class Mytest10 {public static Random Random = new Random ();
    public static int R (int min,int max) {int num=0;
    Num=random.nextint (max-min) +min;
  return num;
    public static void Main (string[] args) throws IOException {//TODO auto-generated stub//create a picture in memory
    int w=120;
    int h=50;
    BufferedImage img = new BufferedImage (W, H, Bufferedimage.type_int_rgb);
    Draw a rectangle on the picture when the background Graphics g = img.getgraphics ();
    G.setcolor (New Color (R (50,250), R (50,250), R (50,250)));
     
    G.fillrect (0, 0, W, h);
    String str = "aqzxswedcfrvgtbhyujklp23456789";
      for (int i=0;i<4;i++) {G.setcolor (new Color (R (50,180), R (50,180), R (50,180)));
      G.setfont (New Font ("bold", font.plain,40)); char C = Str.charat (R (0,str.length ()));
    g.DrawString (String.valueof (c), 10+i*30, R (h-30,h));
      ///Draw random line for (int i=0;i<25;i++) {G.setcolor (new Color (R (50,180), R (50,180), R (50,180)));
    G.drawline (R (0,w), R (0,h), R (0,w), R (0,h));
    ////Output the image created in memory to the file ("Vcode.png") in Files ("=new");
    Imageio.write (IMG, "PNG", file);
     
  System.out.println ("Picture output complete");
 }
 
}

Instance 2:java randomly generates common Chinese character verification code

Import Java.awt.Color;
Import Java.awt.Font;
Import Java.awt.Graphics;
Import Java.awt.Graphics2D;
Import Java.awt.image.BufferedImage;
Import java.io.IOException;
Import Java.util.Random;
Import Javax.imageio.ImageIO;
Import javax.servlet.ServletException;
Import Javax.servlet.http.HttpServlet;
Import Javax.servlet.http.HttpServletRequest;
Import Javax.servlet.http.HttpServletResponse; /** * generates random Chinese characters * * */public class DrawImage extends HttpServlet {public static final int WIDTH = n; public static final
int HEIGHT = 30;
public void doget (HttpServletRequest request, httpservletresponse response) throws Servletexception, IOException {
This.dopost (request, response); public void DoPost (HttpServletRequest request, httpservletresponse response) throws Servletexception, IOException {req
Uest.setcharacterencoding ("Utf-8");
Response.setcontenttype ("Text/html;charset=utf-8");
Create cache BufferedImage bi = new BufferedImage (WIDTH, HEIGHT, Bufferedimage.type_int_rgb); Get the canvas Graphics g = BI.GEtgraphics ();
Set the background color setbackground (g);
Set the Border SetBorder (g);
Draw Disturbing line drawrandomline (g);
Write random number String random = Drawrandomnum ((graphics2d) g);
The existence of random Chinese characters in the session request.getsession (). setattribute ("Checkcode", random);
Write the graph to the browser response.setcontenttype ("Image/jpeg");
Hair Head Control browser do not cache Response.setdateheader ("Expries",-1);
Response.setheader ("Cache-control", "No-cache");
Response.setheader ("Pragma", "No-cache");
Write the picture to the browser imageio.write (bi, "JPG", Response.getoutputstream ()); /** * Set Background color * * @param g */private void SetBackground (Graphics g) {//Set color G.setcolor (color.white);//Fill Area G.fillrect
(0, 0, WIDTH, HEIGHT); /** * Set Border * * @param g/private void SetBorder (Graphics g) {//Set Border color G.setcolor (color.blue);//Border area g.drawrect (1,
1, WIDTH-2, HEIGHT-2); /** * Draw Random lines * * @param g/private void Drawrandomline (Graphics g) {//Set color G.setcolor (color.green);//Set number of lines and draw line for (int i = 0; i < 5; i++) {int x1 = new Random (). Nextint (WIDTH); int y1 = new Random (). Nextint (HeighT);
int x2 = new Random (). Nextint (WIDTH);
int y2 = new Random (). Nextint (HEIGHT);
G.drawline (x1, y1, x2, y2); }/** * Draw random Kanji * * @param g * @return/private String Drawrandomnum (graphics2d g) {StringBuffer sb = new StringBuffer (
);
Set color G.setcolor (color.red);
Sets the font g.setfont (new font ("Arial", Font.Bold, 20)); Prepare common Chinese Character set String base = "\u7684\u4e00\u4e86\u662f\u6211\u4e0d\u5728\u4eba\u4eec\u6709\u6765\u4ed6\u8fd9\u4e0a\ U7740\u4e2a\u5730\u5230\u5927\u91cc\u8bf4\u5c31\u53bb\u5b50\u5f97\u4e5f\u548c\u90a3\u8981\u4e0b\u770b\u5929\ U65f6\u8fc7\u51fa\u5c0f\u4e48\u8d77\u4f60\u90fd\u628a\u597d\u8fd8\u591a\u6ca1\u4e3a\u53c8\u53ef\u5bb6\u5b66\ U53ea\u4ee5\u4e3b\u4f1a\u6837\u5e74\u60f3\u751f\u540c\u8001\u4e2d\u5341\u4ece\u81ea\u9762\u524d\u5934\u9053\ U5b83\u540e\u7136\u8d70\u5f88\u50cf\u89c1\u4e24\u7528\u5979\u56fd\u52a8\u8fdb\u6210\u56de\u4ec0\u8fb9\u4f5c\ U5bf9\u5f00\u800c\u5df1\u4e9b\u73b0\u5c71\u6c11\u5019\u7ecf\u53d1\u5de5\u5411\u4e8b\u547d\u7ed9\u957f\u6c34\ U51e0\u4e49\u4e09\u58f0\u4e8e\u9ad8\u624b\u77e5\u7406\u773c\u5fd7\u70b9\u5fc3\u6218\u4e8c\u95ee\u4f46\u8eab\u65b9\u5b9e\u5403\u505a\u53eb\u5f53\ u4f4f\u542c\u9769\u6253\u5462\u771f\u5168\u624d\u56db\u5df2\u6240\u654c\u4e4b\u6700\u5149\u4ea7\u60c5\u8def\ U5206\u603b\u6761\u767d\u8bdd\u4e1c\u5e2d\u6b21\u4eb2\u5982\u88ab\u82b1\u53e3\u653e\u513f\u5e38\u6c14\u4e94\ U7b2c\u4f7f\u5199\u519b\u5427\u6587\u8fd0\u518d\u679c\u600e\u5b9a\u8bb8\u5feb\u660e\u884c\u56e0\u522b\u98de\ U5916\u6811\u7269\u6d3b\u90e8\u95e8\u65e0\u5f80\u8239\u671b\u65b0\u5e26\u961f\u5148\u529b\u5b8c\u5374\u7ad9\ U4ee3\u5458\u673a\u66f4\u4e5d\u60a8\u6bcf\u98ce\u7ea7\u8ddf\u7b11\u554a\u5b69\u4e07\u5c11\u76f4\u610f\u591c\ U6bd4\u9636\u8fde\u8f66\u91cd\u4fbf\u6597\u9a6c\u54ea\u5316\u592a\u6307\u53d8\u793e\u4f3c\u58eb\u8005\u5e72\ U77f3\u6ee1\u65e5\u51b3\u767e\u539f\u62ff\u7fa4\u7a76\u5404\u516d\u672c\u601d\u89e3\u7acb\u6cb3\u6751\u516b\ U96be\u65e9\u8bba\u5417\u6839\u5171\u8ba9\u76f8\u7814\u4eca\u5176\u4e66\u5750\u63a5\u5e94\u5173\u4fe1\u89c9\ U6b65\u53cd\u5904\u8bb0\u5C06\u5343\u627e\u4e89\u9886\u6216\u5e08\u7ed3\u5757\u8dd1\u8c01\u8349\u8d8a\u5b57\u52a0\u811a\u7d27\u7231\ U7b49\u4e60\u9635\u6015\u6708\u9752\u534a\u706b\u6cd5\u9898\u5efa\u8d76\u4f4d\u5531\u6d77\u4e03\u5973\u4efb\ U4ef6\u611f\u51c6\u5f20\u56e2\u5c4b\u79bb\u8272\u8138\u7247\u79d1\u5012\u775b\u5229\u4e16\u521a\u4e14\u7531\ U9001\u5207\u661f\u5bfc\u665a\u8868\u591f\u6574\u8ba4\u54cd\u96ea\u6d41\u672a\u573a\u8be5\u5e76\u5e95\u6df1\ U523b\u5e73\u4f1f\u5fd9\u63d0\u786e\u8fd1\u4eae\u8f7b\u8bb2\u519c\u53e4\u9ed1\u544a\u754c\u62c9\u540d\u5440\ U571f\u6e05\u9633\u7167\u529e\u53f2\u6539\u5386\u8f6c\u753b\u9020\u5634\u6b64\u6cbb\u5317\u5fc5\u670d\u96e8\ U7a7f\u5185\u8bc6\u9a8c\u4f20\u4e1a\u83dc\u722c\u7761\u5174\u5f62\u91cf\u54b1\u89c2\u82e6\u4f53\u4f17\u901a\ U51b2\u5408\u7834\u53cb\u5ea6\u672f\u996d\u516c\u65c1\u623f\u6781\u5357\u67aa\u8bfb\u6c99\u5c81\u7ebf\u91ce\ U575a\u7a7a\u6536\u7b97\u81f3\u653f\u57ce\u52b3\u843d\u94b1\u7279\u56f4\u5f1f\u80dc\u6559\u70ed\u5c55\u5305\ U6b4c\u7c7b\u6e10\u5f3a\u6570\U4e61\u547c\u6027\u97f3\u7b54\u54e5\u9645\u65e7\u795e\u5ea7\u7ae0\u5e2e\u5566\u53d7\u7cfb\u4ee4\u8df3\u975e\ U4f55\u725b\u53d6\u5165\u5cb8\u6562\u6389\u5ffd\u79cd\u88c5\u9876\u6025\u6797\u505c\u606f\u53e5\u533a\u8863\
U822c\u62a5\u53f6\u538b\u6162\u53d4\u80cc\u7ec6 ";
int x = 5; Control word for (int i = 0; i < 4; i++) {//Set font rotation angle int degree = new Random (). Nextint ()% 30;//intercept kanji String ch = base.ch
Arat (New Random (). Nextint (Base.length ())) + "";
Sb.append (CH);
Forward angle g.rotate (degree * math.pi/180, X, 20);
g.DrawString (CH, x, 20);
Reverse Angle g.rotate (-degree * math.pi/180, X, 20);
x + 30;
return sb.tostring ();

 }
}

Above is the Java generated picture verification code, Chinese character verification Code related code, I hope to help you learn.