java生成验证码(支持中文)

PictureCheckCode.java    
   
import java.awt.BasicStroke;    
import java.awt.Color;    
import java.awt.Font;    
import java.awt.Graphics;    
import java.awt.Graphics2D;    
import java.awt.geom.AffineTransform;    
import java.awt.geom.Line2D;    
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;    
import javax.servlet.http.HttpSession;    
   
import com.tools.MD5;    
   
public class PictureCheckCode extends HttpServlet{    
   
 private static final long serialVersionUID = 1L;    
     
 private Random rand=new Random();    
     
     
 /**   
  * 生成随机颜色   
  *    
  * @param   start  [int]   
  * @param   end    [int]   
  * @return  Color  [object]   
  */   
 public Color getRandColor(int start,int end){    
  int randNum;    
  if(start>255) start=255;    
  if(end>255) end=255;    
  if(start>end) randNum=start-end;    
  else randNum=end-start;    
  int r=start+rand.nextInt(randNum);    
  int g=start+rand.nextInt(randNum);    
  int b=start+rand.nextInt(randNum);    
  return new Color(r,g,b);    
 }    
     
     
 /**   
  * 着色\旋转\缩放   
  *    
  * @param word 文字   
  * @param g    图片对象   
  */   
 public void coloredAndRotation(String word,int i,Graphics g){    
  /**着色**/   
  g.setColor(new Color(20+rand.nextInt(110),20+rand.nextInt(110),20+rand.nextInt(110)));    
  /**旋转**/   
  Graphics2D g2d=(Graphics2D)g;    
  AffineTransform trans=new AffineTransform();    
  trans.rotate(rand.nextInt(45)*3.14/180,15*i+8,7);    
  /**缩放**/   
  float scaleSize=rand.nextFloat()+0.8f;    
  if(scaleSize>1f) scaleSize=1f;    
  trans.scale(scaleSize, scaleSize);    
  g2d.setTransform(trans);    
  g.drawString(word,15*i+20,20);    
 }    
     
 /**   
  * 生成100条干扰线   
  *    
  * @param g2d   
  * @param width   
  * @param height   
  */   
 public void getRandLine(Graphics2D g2d,int width,int height){    
  for(int i=0;i<100;i++){    
   int x=rand.nextInt(width-1);    
   int y=rand.nextInt(height-1);    
   int z=rand.nextInt(6)+1;    
   int w=rand.nextInt(12)+1;    
       
   BasicStroke bs=new BasicStroke(2f,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL);    
   Line2D line=new Line2D.Double(x,y,x+z,y+w);    
   g2d.setStroke(bs);    
   g2d.draw(line);    
  }    
 }    
     
 /**   
  * 获取随机文字   
  *    
  * @param  length [int]        验证码长度   
  * @param  g      [Graphics]   图片对象   
  * @return String   
  * @case1:A-Z   
  * @case2:chinese   
  * @default:0-9   
  */   
 @SuppressWarnings("unused")    
 public String getRandWord(int length,Graphics g){    
  String finalWord="",firstWord="";    
  int tempInt=0;    
  String[] array={    
    "0","1","2","3",    
    "4","5","6","7",    
    "8","9","a","b",    
    "c","d","e","f"};    
      
  for(int i=0;i<length;i++){    
   switch(rand.nextInt(2)){    
    case 1:    
      tempInt=rand.nextInt(26)+65;    
      firstWord=String.valueOf((char)tempInt);    
      break;    
    /*case 2:   
      int r1,r2,r3,r4;   
      String strH,strL;//high&low   
      r1=rand.nextInt(3)+11; //前闭后开[11,14)   
      if(r1==13){   
       r2=rand.nextInt(7);   
      }else{   
       r2=rand.nextInt(16);   
      }   
         
      r3=rand.nextInt(6)+10;   
      if(r3==10){   
       r4=rand.nextInt(15)+1;   
      }else if(r3==15){   
       r4=rand.nextInt(15);   
      }else{   
       r4=rand.nextInt(16);   
      }   
         
      strH=array[r1]+array[r2];   
      strL=array[r3]+array[r4];   
         
      byte[] bytes=new byte[2];   
      bytes[0]=(byte)(Integer.parseInt(strH,16));   
      bytes[1]=(byte)(Integer.parseInt(strL,16));   
         
      firstWord=new String(bytes);   
      break;*/   
    default:    
      tempInt=rand.nextInt(10)+48;    
      firstWord=String.valueOf((char)tempInt);    
      break;    
   }    
   finalWord+=firstWord;    
   this.coloredAndRotation(firstWord,i, g);    
  }    
      
  return finalWord;    
 }    
   
 protected void service(HttpServletRequest request, HttpServletResponse response)    
   throws ServletException, IOException {    
      
  //设制不缓存图片    
  response.setHeader("Pragma","No-cache");    
  response.setHeader("Cache-Control","No-cache");    
  response.setDateHeader("Expires",0);    
      
  //生成图片    
  response.setContentType("image/jpeg");    
  int width=100;    
  int height=40;    
  BufferedImage image=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);    
      
  Graphics g=image.getGraphics();    
  Graphics2D g2d=(Graphics2D)g;    
  Font mFont=new Font("宋体",Font.BOLD,22);    
  g.setColor(this.getRandColor(200,250));    
  g.fillRect(0, 0, width, height);    
  g.setFont(mFont);    
  g.setColor(this.getRandColor(180,200));    
      
  this.getRandLine(g2d, width, height);    
      
  String randCode=this.getRandWord(4, g);    
      
  HttpSession session=request.getSession();    
  session.setAttribute("randCode",MD5.code(randCode.toLowerCase()));    
      
  g.dispose();    
      
  ImageIO.write(image,"JPEG",response.getOutputStream());    
      
 }    
}