java 線上圖檔驗證碼生成代碼_Java代碼生成圖檔驗證碼實作

介紹一個使用Java代碼生成随機圖檔驗證碼的示例 可以直接配置成Servlet，在頁面直接調用 Java代碼随機生成圖檔驗證碼 package com.rchm.util.images; import java.awt.Color; import java.awt.Font; import java.awt.Graphics2D; import java.awt.image.Buff

介紹一個使用Java代碼生成随機圖檔驗證碼的示例

可以直接配置成Servlet，在頁面直接調用

Java代碼随機生成圖檔驗證碼

package com.rchm.util.images;

import java.awt.Color;

import java.awt.Font;

import java.awt.Graphics2D;

import java.awt.image.BufferedImage;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Random;

import javax.imageio.ImageIO;

public class ValidateCode {

// 圖檔的寬度。

private int width = 160;

// 圖檔的高度。

private int height = 40;

// 驗證碼字元個數

private int codeCount = 5;

// 驗證碼幹擾線數

private int lineCount = 150;

// 驗證碼

private static String code = null;

// 驗證碼圖檔Buffer

private BufferedImage buffImg=null;

private char[] codeSequence = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J','K', 'L',

'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W','X', 'Y',

'Z', '1', '2', '3', '4', '5', '6', '7', '8', '9' };

public ValidateCode() {

this.createCode();

}

public ValidateCode(int width,int height) {

this.width=width;

this.height=height;

this.createCode();

}

public ValidateCode(int width,int height,int codeCount,int lineCount) {

this.width=width;

this.height=height;

this.codeCount=codeCount;

this.lineCount=lineCount;

this.createCode();

}

public void createCode() {

int x = 0,fontHeight=0,codeY=0;

int red = 0, green = 0, blue = 0;

x = width / (codeCount +2);//每個字元的寬度

fontHeight = height - 2;//字型的高度

codeY = height - 4;

// 圖像buffer

buffImg = new BufferedImage(width, height,BufferedImage.TYPE_INT_RGB);

Graphics2D g = buffImg.createGraphics();

// 生成随機數

Random random = new Random();

// 将圖像填充為白色

g.setColor(Color.WHITE);

g.fillRect(0, 0, width, height);

// 建立字型

ImgFontByte imgFont=new ImgFontByte();

Font font =imgFont.getFont(fontHeight);

g.setFont(font);

for (int i = 0; i

int xs = random.nextInt(width);

int ys = random.nextInt(height);

int xe = xs+random.nextInt(width/8);

int ye = ys+random.nextInt(height/8);

red = random.nextInt(255);

green = random.nextInt(255);

blue = random.nextInt(255);

g.setColor(new Color(red, green, blue));

g.drawLine(xs, ys, xe, ye);

}

// randomCode記錄随機産生的驗證碼

StringBuffer randomCode = new StringBuffer();

// 随機産生codeCount個字元的驗證碼。

for (int i = 0; i

String strRand = String.valueOf(codeSequence[random.nextInt(codeSequence.length)]);

// 産生随機的顔色值，，讓輸出的每個字元的顔色值都将不同。

red = random.nextInt(255);

green = random.nextInt(255);

blue = random.nextInt(255);

g.setColor(new Color(red, green, blue));

g.drawString(strRand, (i + 1) * x, codeY);

// 将産生的四個随機數組合在一起。

randomCode.append(strRand);

}

// 将四位數字的驗證碼儲存到Session中。

code = randomCode.toString();

}

public void write(String path) throws IOException {

OutputStream sos = new FileOutputStream(path);

this.write(sos);

}

public void write(OutputStream sos) throws IOException {

ImageIO.write(buffImg, "png", sos);

sos.close();

}

public BufferedImage getBuffImg() {

return buffImg;

}

public static String getCode() {

return code;

}

}

在 servlet 中使用該類：

package com.rchm.util.images;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

public class ValidateCodeServlet extends HttpServlet {

private static final long serialVersionUID = 1L;

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

response.setContentType("image/jpeg");

response.setHeader("Pragma", "no-cache");

response.setHeader("Cache-Control", "no-cache");

response.setDateHeader("Expires", 0);

ValidateCode vCode = new ValidateCode(100,30,4,100);

HttpSession session = request.getSession();

session.removeAttribute("validateCode");

vCode.write(response.getOutputStream());

session.setAttribute("validateCode", vCode.getCode());

vCode.write(response.getOutputStream());

}

}

在 web.xml配置Servlet通路路徑：

validateCodeServlet

class>com.rchm.util.images.ValidateCodeServletclass>

validateCodeServlet