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[java]代码库

package a;

import java.awt.Color;
import java.awt.Font;
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;

public class VerifyCode extends HttpServlet {
	
	private final int width = 120;
	private final int height = 30;

	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		BufferedImage img = new BufferedImage(width, height, BufferedImage.TYPE_INT_BGR);
		
		Graphics2D g = (Graphics2D) img.getGraphics();
		
		g.setColor(Color.white);
		g.fillRect(0, 0, width, height);
		
		g.setColor(Color.blue);
		g.drawRect(0, 0, width-1, height-1);
		
		String base = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
		
		Random ran = new Random();
		
		g.setFont(new Font("宋体",Font.BOLD,20));
		
		int x = 0, y = 20;
		String value="";
		for(int i = 1; i<=4; i++){
			
			int index = ran.nextInt(base.length());
			char ch = base.charAt(index);
			
			int degree = ran.nextInt(60) -30;
			double theta = degree*Math.PI;
			
			g.rotate(theta, x+20*i, 15);
			g.drawString(ch+"", x+20*i, y);
			g.rotate(-theta, x+20*i,15);
			
			value+=ch;
			
		}
		request.getSession().setAttribute("value",value); 
		
		g.setColor(Color.yellow);
		int x1,y1,x2,y2;
		for(int i = 1; i<=5; i++){
			
			x1 = ran.nextInt(width);
			y1 = ran.nextInt(height);
			x2 = ran.nextInt(width);
			y2 = ran.nextInt(height);
			g.drawLine(x1, y1, x2, y2);
			
		}
		
		
		g.dispose();
		
		ImageIO.write(img, "jpg", response.getOutputStream());
		
	}


	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		doGet(request, response);
		
	}

}

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