創建隨機驗證碼

<pre name="code" class="java">package image;


import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.GradientPaint;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.security.cert.Certificate;
import java.util.Random;


import javax.imageio.ImageIO;


import org.hibernate.validator.constraints.Length;
import org.junit.Test;


public class VerrifyCode {
	private int w=70;
	private int h=35;
	private Random r = new Random();
	//設置字體
	private String[] fontNames= {"宋體","華文楷體","黑體","微軟雅黑","楷體_GB2312"};
	//可選字母
	private String codes="23456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ";
	//背景色
	private Color bgColor = new Color(255,255,255);
	//驗證碼上的文字
	private String text;
	
	// 生成隨機的顏色
	private Color randomColor(){
		int red =r.nextInt(150);
		int green =r.nextInt(150);
		int blue = r.nextInt(150);
		return new Color(red,green,blue);
	}
	
	//生成隨機的字體
	private Font randomFont(){
		int index = r.nextInt(fontNames.length);
		String fontName = fontNames[index];// 生成隨機的字體名稱	
		int style = r.nextInt(4);//生成隨機樣式 0(無樣式),1(粗體),2(斜體),3(粗+斜體)
		int size = r.nextInt(5)+24;// 生成隨機字號  24~28
		return new Font(fontName,style,size);
	}
	
	//畫干擾線
	private void drawLine(BufferedImage image){
		int num =3;//總共三條線
		Graphics2D g2 = (Graphics2D)image.getGraphics();
		for(int i=0;i<num;i++){//生成兩個點的座標，四個值
			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));
			g2.setColor(Color.BLUE);// 線是藍色
			g2.drawLine(x1, y1, x2, y2);// 劃線
		}
	}
	
	//隨機生成一個字符
	private char randomChar(){
		int index = r.nextInt(codes.length());
		return codes.charAt(index);
	}
	//創建BufferedImage
	private BufferedImage createImage(){
		BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
		Graphics2D g2 = (Graphics2D)image.getGraphics();
		g2.setColor(this.bgColor);
		g2.fillRect(0, 0, w, h);
		return image;
	}
	
	//調用這個方法獲取驗證碼
	public BufferedImage getImage(){
		BufferedImage image = createImage();// 創建圖片緩衝區
		Graphics2D g2 = (Graphics2D)image.getGraphics();//得到繪製環境
		StringBuilder sb = new StringBuilder();//用來裝載生成的驗證碼文本
		//像圖片中畫4個字符
		for(int i=0;i<4;i++){//循環4次，每次生成一個字符
			String s = randomChar()+"";//隨機生成一個字符
			sb.append(s);//把字符添加到sd中
			float x=i*1.0F*w/4;//設置當前座標的x軸
			g2.setFont(randomFont());//設置隨機字體
			g2.setColor(randomColor());//設置隨機顏色
			g2.drawString(s, x, h-5);//畫圖
		}
		this.text=sb.toString();// 把生成的字符串給了this.text
		drawLine(image);//添加干擾線
		return image;
	}
	
	// 返回驗證碼上的文字
	public String getText(){
		return text;
	}
	
	// 保存圖片到指定的輸出流
	public static void output (BufferedImage image,OutputStream out)
		throws IOException{
		ImageIO.write(image, "JPEG", out);
		
		
	}
	@Test
	//運行~
	public void fun() throws FileNotFoundException,IOException{
		VerrifyCode vc = new VerrifyCode();
		BufferedImage bi =vc.getImage();
		VerrifyCode.output(bi,new FileOutputStream("F:/xxx.jpg") );
		
		System.out.println(vc.getText());
	}
}