【Java 二维码】生成二维码

package utils;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.InputStream;
import java.util.EnumMap;

import javax.imageio.ImageIO;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

/**
 * 生成二维码
 */
public class ZXingCodeEncodeUtils {

    public static void main(String[] args) {
        //        createZXingCodeSaveToDisk("kikyo", 400, 400, "D:/kikyo.gif", "JPEG");
        InputStream logoStream = ZXingCodeEncodeUtils.class.getClassLoader().getResourceAsStream("image/logo.jpg");
        createZxingCodeUseLogoSaveToDisk("kikyo", 400, 400, "D:/kikyo.jpg", "JPEG", logoStream);
        System.out.println("生成成功");
    }

    // 二维码颜色
    private static final int BLACK = 0xFF000000;
    // 二维码背景颜色
    private static final int WHITE = 0xFFFFFFFF;

    // 二维码格式参数
    private static final EnumMap<EncodeHintType, Object> hints = new EnumMap<EncodeHintType, Object>(EncodeHintType.class);

    static {
        /*
         * 二维码的纠错级别(排错率),4个级别： L (7%)、 M (15%)、 Q (25%)、 H (30%)(最高H)
         * 纠错信息同样存储在二维码中，纠错级别越高，纠错信息占用的空间越多，那么能存储的有用讯息就越少；共有四级； 选择M，扫描速度快。
         */
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        // 二维码边界空白大小 1,2,3,4 (4为默认,最大)
        hints.put(EncodeHintType.MARGIN, 1);
        hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");// 设置放入的字符的编码
    }

    /**
     * 生成二维码保存到目标路径
     */
    public static void createZXingCodeSaveToDisk(String content, int width, int height, String savePath, String imageType) {
        try {
            BufferedImage image = createZXingCodeNormal(content, width, height);
            // 保存图片到硬盘
            File file = new File(savePath);
            if (!file.exists()) {
                file.createNewFile();
            }
            ImageIO.write(image, imageType, file);
            System.out.println("生成成功");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 生成二维码返回图片对象
     */
    public static BufferedImage createZXingCodeNormal(String content, int width, int height) {
        try {
            BitMatrix encode = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, width, height, hints);
            // 得到二维码的宽度
            int code_width = encode.getWidth();
            int code_height = encode.getHeight();
            // 创建图片
            BufferedImage image = new BufferedImage(code_width, code_height, BufferedImage.TYPE_INT_RGB);
            // 把二维码里面的信息写到图片里面
            for (int i = 0; i < code_width; i++) {
                for (int j = 0; j < code_height; j++) {
                    image.setRGB(i, j, encode.get(i, j) ? BLACK : WHITE);
                }
            }
            return image;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }


    /**
     * 生成一张带logo的二维码
     *
     * @param logoStream logo的流对象
     */
    public static void createZxingCodeUseLogoSaveToDisk(String content, int width, int height, String savePath,
                                                        String imageType, InputStream logoStream) {
        try {
            BufferedImage codeImage = createZxingCodeUseLogo(content, width, height, logoStream);
            // 保存图片到硬盘
            File file = new File(savePath);
            if (!file.exists()) {
                file.createNewFile();
            }
            ImageIO.write(codeImage, imageType, file);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 生成一张带logo的二维码  返回BuffredeImage
     *
     * @param logoStream logo的流对象
     */
    public static BufferedImage createZxingCodeUseLogo(String content, int width, int height, InputStream logoStream) {
        try {
            //生成二维码图片
            BufferedImage codeNormal = createZXingCodeNormal(content, width, height);
            //判断logoStream是否为空
            if (null == codeNormal || null == logoStream) {
                System.out.println("codeNormal or logoStream is null");
                return null;
            }
            //拿到可以操作当前图片的画笔
            Graphics2D graphics = codeNormal.createGraphics();
            //得到logo图片的对象
            BufferedImage logoImage = ImageIO.read(logoStream);
            //得到logo的原始宽高
            int old_logo_width = logoImage.getWidth();
            int old_logo_height = logoImage.getHeight();

            //得到二维码的宽高
            int code_width = codeNormal.getWidth();
            int code_height = codeNormal.getHeight();

            //算出logo在二维码里面能存在的最大值
            int logo_max_width = code_width / 5;
            int logo_max_height = code_height / 5;

            //计算logo的可用宽高
            int logo_width = logo_max_width < old_logo_width ? logo_max_width : old_logo_width;
            int logo_height = logo_max_height < old_logo_height ? logo_max_height : old_logo_height;

            //计算logo的开始点的坐标
            int x = (code_width - logo_width) / 2;
            int y = (code_height - logo_height) / 2;

            /**
             * logoImage logo图片对象
             * x 开始画的x轴坐标
             * y 开始画的y轴的坐
             * logo_width 要画的x轴的长度
             * logo_height 要画的y车的长度
             * arg5  null
             */
            graphics.drawImage(logoImage, x, y, logo_width, logo_height, null);

            graphics.setStroke(new BasicStroke(2));
            graphics.setColor(Color.WHITE);
            //画白色边框
            graphics.drawRoundRect(x, y, logo_width, logo_height, 15, 15);
            graphics.dispose();//让画上的去的内容生效
            return codeNormal;
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("生成失败  " + e.getMessage());
            return null;
        }
    }
}

package utils;

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.util.EnumMap;

import javax.imageio.ImageIO;

import com.google.zxing.Binarizer;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.LuminanceSource;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.Result;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.common.HybridBinarizer;

/**
 * 解析二维码
 */
public class ZXingCodeDecodeUtils {

    public static void main(String[] args) throws FileNotFoundException {
        //  String string = decodeCodeFile("D:/kikyo.gif");
        String string = decodeCodeStream(new FileInputStream(new File("D:/kikyo.jpg")));
        System.out.println(string);
    }

    // 二维码格式参数
    private static final EnumMap<DecodeHintType, Object> decodeHints = new EnumMap<DecodeHintType, Object>(DecodeHintType.class);

    static {
        decodeHints.put(DecodeHintType.CHARACTER_SET, "UTF-8");
    }

    /**
     * 解析文件
     */
    public static String decodeCodeFile(String path) {
        File file = new File(path);
        if (!file.exists())
            return null;
        // 把文件转成图片对象
        try {
            String content = decodeCodeStream(new FileInputStream(file));
            return content;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 解析流
     */
    public static String decodeCodeStream(InputStream inputStream) {
        if (null == inputStream)
            return null;
        try {
            BufferedImage image = ImageIO.read(inputStream);
            LuminanceSource source = new BufferedImageLuminanceSource(image);
            Binarizer binarizer = new HybridBinarizer(source);
            BinaryBitmap binaryBitmap = new BinaryBitmap(binarizer);
            MultiFormatReader reader = new MultiFormatReader();
            Result result = reader.decode(binaryBitmap, decodeHints);
            String content = result.getText();
            return content;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

@WebServlet("/code.action")
public class CodeServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

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

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //生成图片
//        BufferedImage codeImage=ZXingCodeEncodeUtils.createZXingCodeNormal("kikyo", 300, 300);
        InputStream logoStream = this.getClass().getClassLoader().getResourceAsStream("/image/logo.jpg");
        BufferedImage codeImage = ZXingCodeEncodeUtils.createZxingCodeUseLogo("kikyo", 300, 300, logoStream);

        ServletOutputStream outputStream = response.getOutputStream();
        ImageIO.write(codeImage, "JPEG", outputStream);
        outputStream.close();
    }
}

@WebServlet("/decode.action")
@MultipartConfig
public class DeCodeServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

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

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        Part part = request.getPart("mf");
        request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8");
        String string = ZXingCodeDecodeUtils.decodeCodeStream(part.getInputStream());
        PrintWriter out = response.getWriter();
        out.write(string);
        out.flush();
        out.close();
    }
}

<img alt="" src="code.action" >
<form action="decode.action" method="post" enctype="multipart/form-data">
    <input type="file" name="mf">
    <input type="submit" value="解析">
</form>

        <!-- servlet -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.0.1</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.annotation</groupId>
            <artifactId>javax.annotation-api</artifactId>
            <version>1.2</version>
        </dependency>
        <dependency>
            <groupId>jstl</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>

        <!-- ZXing -->
        <dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>core</artifactId>
            <version>3.3.3</version>
        </dependency>
        <dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>javase</artifactId>
            <version>3.3.3</version>
        </dependency>