java验证码生成方法(带中文哦)

效果图: 


代码:
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());
  
 }
}

转载地址：http://www.dukai168.cn/blog/5.html