手把手教你生成二维码-google.zxing

时间:2024-03-05 16:55:50

一、目标

输入网址,生成网址的二维码

二、概况

1.效果:UI丑,但功能实现了

 

2.项目目录

 

三、用到的第三方资源

1.google的扫码包zxing

2.JQuery

四、步骤(用myEclipse)

1.新建工程,选择web project

2.加入第三方资源(zxing包和jQuery)

2.1

2.1.1复制,粘贴,加入zxing的jar包(所有文件在附件中下载)

2.2.2右键jar包加入buildpath

2.2加入jQuery文件

2.2.1在WebRoot下新建文件夹js

复制粘贴jQuery文件到此文件夹

3.按需求修改webroot下的index.jsp页面如下:

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    <title>二维码</title>
    <script src="js/jquery.min.js"></script>
    <script>
    	$(function(){
    		$("input[type=submit]").click(function(e){
    			e.preventDefault();
    			$("#qrcode_div").empty().append("<img id=\'qrImg\' />");
    			$("#qrImg").attr("src", "qrcode?website="+$("input[type=text][name=website]").val());//此处会访问servlet
    		});
    	});
    </script>
  </head>
  
  <body>
    <form>
    	网址<input type="text" name="website" />
    	<input type="submit" value="生成二维码" />
    	<div id="qrcode_div"></div>
    </form>
  </body>
</html>

4.新建servlet文件

4.1右键工程文件夹--》new ---->servlet(myEclipse会自动配置servlet到web.xml文件)

QRCode.java servlet文件的代码如下:

package servlet;
import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import util.QRCodeUtil;

import com.google.zxing.WriterException;


public class QRCode extends HttpServlet {
	
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		
		request.setCharacterEncoding("utf-8");
		response.setCharacterEncoding("utf-8");
		String website = request.getParameter("website");
		try {
			QRCodeUtil.genGR(website, response.getOutputStream());
		} catch (WriterException e) {
			e.printStackTrace();
		}
		//String website = request.getAttribute("website").toString();
	}

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

}

5.新建辅助类文件,作用是生成二维码(QRCodeUtil.java)

5.1右键工程文件夹--》new--->class,如下图

 

QRCodeUtil.java的代码如下:

package util2;

import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Hashtable;

import javax.imageio.ImageIO;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;

public class QRCodeUtil {
	
	private static final int BLACK = 0xFF000000;
	private static final int WHITE = 0xFFFFFFFF;
	
	public static void genGR(String website, OutputStream output) throws WriterException, IOException {
		int width = 300;
		int height = 300;
		String format = "jpg";
        Hashtable<EncodeHintType, String> hints = new Hashtable<EncodeHintType, String>(); 
        //Hashtable hints = new Hashtable();
        hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
		BitMatrix bm = new MultiFormatWriter().encode(website, BarcodeFormat.QR_CODE, width, height, hints);
		
		BufferedImage image = toImage(bm);
		ImageIO.write(image, format, output);	//把二维码写到response的输出流
	}

	private static BufferedImage toImage(BitMatrix bm) {
		int width = bm.getWidth();
		int height = bm.getHeight();
		BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
		for(int x = 0;x < width; x++){
			for(int y = 0; y < height; y++ ){
				image.setRGB(x, y, bm.get(x, y) ? BLACK : WHITE);
			}
		}
		return image;
	}

}

6.至此,所有文件已完成,接下来布置项目,启动tomcat,访问文件,如下图

布置完成后,点击debug启动项目

启动成功后,在浏览器中访问文件

PS:

可以修改QRCodeUtil.java文件中的颜色配置,以生成彩色的二维码,例如:

private static final int BLACK = 0xff0000ff;//0xFF000000;
private static final int WHITE = 0xffffff00;//0xFFFFFFFF;

常见颜色代码如下:

这些颜色常数是定义在android.graphics.Color里的:

类型

常数

色码

int

BLACK

-16777216

0xff000000

int

BLUE

-16776961

0xff0000ff

int

CYAN

-16711681

0xff00ffff

int

DKGRAY

-12303292

0xff444444

int

GRAY

-7829368

0xff888888

int

GREEN

-16711936

0xff00ff00

int

LTGRAY

-3355444

0xffcccccc

int

MAGENTA

-65281

0xffff00ff

int

RED

-65536

0xffff0000

int

TRANSPARENT

0

0x00000000

int

WHITE

-1

0xffffffff

int

YELLOW

-256

0xffffff00

 

项目附件:

https://files.cnblogs.com/files/shamgod/QRCode.zip