我们在开发的时候,有的时候需要将很多数据类型(如图片或者excel)导出去,这个时候就需要将很多数据导出到zip压缩文件中。

我们以将url转换成图片然后存储到zip上为里。

逻辑比较简单,先将url链接转换成图片,然后将图片合并到zip中,最后导出去。

一:首先引用jar包

<dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>core</artifactId>
            <version>3.3.0</version>
        </dependency>
        <dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>javase</artifactId>
            <version>3.3.0</version>
        </dependency>

二:准备将url链接转换成图片的工具类util。

import com.google.zxing.*;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.OutputStream;
import java.util.Hashtable;
import java.util.Random;

/**
 * 转换图片类
 */

public class QRCodeUtil {
    private static final String CHARSET = "utf-8";
    private static final String FORMAT_NAME = "JPG";
    // 二维码尺寸
    private static final int QRCODE_SIZE = 300;
    // LOGO宽度
    private static final int WIDTH = 60;
    // LOGO高度
    private static final int HEIGHT = 60;

    private static BufferedImage createImage(String content, String imgPath,
                                             boolean needCompress) throws Exception {
        Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
        hints.put(EncodeHintType.MARGIN, 1);
        BitMatrix bitMatrix = new MultiFormatWriter().encode(content,
                BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE, hints);
        int width = bitMatrix.getWidth();
        int height = bitMatrix.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, bitMatrix.get(x, y) ? 0xFF000000
                        : 0xFFFFFFFF);
            }
        }
        if (imgPath == null || "".equals(imgPath)) {
            return image;
        }
        // 插入图片
        QRCodeUtil.insertImage(image, imgPath, needCompress);
        return image;
    }

    /**
     * 插入LOGO
     *
     * @param source       二维码图片
     * @param imgPath      LOGO图片地址
     * @param needCompress 是否压缩
     * @throws Exception
     */
    private static void insertImage(BufferedImage source, String imgPath,
                                    boolean needCompress) throws Exception {
        File file = new File(imgPath);
        if (!file.exists()) {
            System.err.println("" + imgPath + "   该文件不存在!");
            return;
        }
        Image src = ImageIO.read(new File(imgPath));
        int width = src.getWidth(null);
        int height = src.getHeight(null);
        if (needCompress) { // 压缩LOGO
            if (width > WIDTH) {
                width = WIDTH;
            }
            if (height > HEIGHT) {
                height = HEIGHT;
            }
            Image image = src.getScaledInstance(width, height,
                    Image.SCALE_SMOOTH);
            BufferedImage tag = new BufferedImage(width, height,
                    BufferedImage.TYPE_INT_RGB);
            Graphics g = tag.getGraphics();
            g.drawImage(image, 0, 0, null); // 绘制缩小后的图
            g.dispose();
            src = image;
        }
        // 插入LOGO
        Graphics2D graph = source.createGraphics();
        int x = (QRCODE_SIZE - width) / 2;
        int y = (QRCODE_SIZE - height) / 2;
        graph.drawImage(src, x, y, width, height, null);
        Shape shape = new RoundRectangle2D.Float(x, y, width, width, 6, 6);
        graph.setStroke(new BasicStroke(3f));
        graph.draw(shape);
        graph.dispose();
    }

    /**
     * 生成二维码(内嵌LOGO)
     *
     * @param content      内容
     * @param imgPath      LOGO地址
     * @param destPath     存放目录
     * @param needCompress 是否压缩LOGO
     * @throws Exception
     */
    public static String encode(String content, String imgPath, String destPath,
                                boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, imgPath,
                needCompress);
        mkdirs(destPath);
        String file = new Random().nextInt(99999999) + ".jpg";
        ImageIO.write(image, FORMAT_NAME, new File(destPath + "/" + file));
        return destPath + "/" + file;
    }


    public static String encodeName(String content, String imgPath, String destPath, String name,
                                    boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, imgPath,
                needCompress);
        mkdirs(destPath);
        String file = name + ".jpg";
        ImageIO.write(image, FORMAT_NAME, new File(destPath + "/" + file));
        return destPath + "/" + file;
    }

    /**
     * 当文件夹不存在时,mkdirs会自动创建多层目录,区别于mkdir.(mkdir如果父目录不存在则会抛出异常)
     *
     * @param destPath 存放目录
     */
    public static void mkdirs(String destPath) {
        File file = new File(destPath);
        //当文件夹不存在时,mkdirs会自动创建多层目录,区别于mkdir.(mkdir如果父目录不存在则会抛出异常)
        if (!file.exists() && !file.isDirectory()) {
            file.mkdirs();
        }
    }

    /**
     * 生成二维码(内嵌LOGO)
     *
     * @param content  内容
     * @param imgPath  LOGO地址
     * @param destPath 存储地址
     * @throws Exception
     */
    public static void encode(String content, String imgPath, String destPath)
            throws Exception {
        QRCodeUtil.encode(content, imgPath, destPath, false);
    }

    /**
     * 生成二维码
     *
     * @param content      内容
     * @param destPath     存储地址
     * @param needCompress 是否压缩LOGO
     * @throws Exception
     */
    public static void encode(String content, String destPath,
                              boolean needCompress) throws Exception {
        QRCodeUtil.encode(content, null, destPath, needCompress);
    }

    /**
     * 生成二维码
     *
     * @param content  内容
     * @param destPath 存储地址
     * @throws Exception
     */
    public static void encode(String content, String destPath) throws Exception {
        QRCodeUtil.encode(content, null, destPath, false);
    }

    /**
     * 生成二维码(内嵌LOGO)
     *
     * @param content      内容
     * @param imgPath      LOGO地址
     * @param output       输出流
     * @param needCompress 是否压缩LOGO
     * @throws Exception
     */
    public static void encode(String content, String imgPath,
                              OutputStream output, boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, imgPath,
                needCompress);
        ImageIO.write(image, FORMAT_NAME, output);
    }

    /**
     * 生成二维码
     *
     * @param content 内容
     * @param output  输出流
     * @throws Exception
     */
    public static void encode(String content, OutputStream output)
            throws Exception {
        QRCodeUtil.encode(content, null, output, false);
    }

    /**
     * 解析二维码
     *
     * @param file 二维码图片
     * @return
     * @throws Exception
     */
    public static String decode(File file) throws Exception {
        BufferedImage image;
        image = ImageIO.read(file);
        if (image == null) {
            return null;
        }
        BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(
                image);
        BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
        Result result;
        Hashtable<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();
        hints.put(DecodeHintType.CHARACTER_SET, CHARSET);
        result = new MultiFormatReader().decode(bitmap, hints);
        String resultStr = result.getText();
        return resultStr;
    }

    /**
     * 解析二维码
     *
     * @param path 二维码图片地址
     * @return
     * @throws Exception
     */
    public static String decode(String path) throws Exception {
        return QRCodeUtil.decode(new File(path));
    }

    /**
     * @param content
     * @param imgPath
     * @param destPath
     * @param localUrl     当前环境的域名或者ip地址
     * @param needCompress
     * @return
     * @throws Exception
     */
    public static String encode(String content, String imgPath, String destPath, String localUrl,
                                boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, imgPath,
                needCompress);
        mkdirs(destPath);
        String file = new Random().nextInt(99999999) + ".jpg";
        ImageIO.write(image, FORMAT_NAME, new File(destPath + "/" + file));
        return localUrl + file;
    }

    public static String encodeDZ(String content, String imgPath, String destPath, String localUrl, int length, int width,
                                  boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImageDZ(content, imgPath, length, width,
                needCompress);
        mkdirs(destPath);
        String file = new Random().nextInt(99999999) + ".jpg";
        ImageIO.write(image, FORMAT_NAME, new File(destPath + "/" + file));
        return localUrl + file;
    }

    private static BufferedImage createImageDZ(String content, String imgPath, int newlength, int newWidth,
                                               boolean needCompress) throws Exception {
        Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
        hints.put(EncodeHintType.MARGIN, 1);
        BitMatrix bitMatrix = new MultiFormatWriter().encode(content,
                BarcodeFormat.QR_CODE, newlength, newWidth, hints);
        int width = bitMatrix.getWidth();
        int height = bitMatrix.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, bitMatrix.get(x, y) ? 0xFF000000
                        : 0xFFFFFFFF);
            }
        }
        if (imgPath == null || "".equals(imgPath)) {
            return image;
        }
        // 插入图片
        QRCodeUtil.insertImage(image, imgPath, needCompress);
        return image;
    }
    
}

三:将很多图片打包zip,并且到处去。

/**
     * 将文件导出去
     * @param response
     * @param list
     * @throws Exception
     */
    public void exportZip(HttpServletResponse response,List<Map> list)throws Exception{
        List<Map<String, String>> picUrls = new ArrayList<>();
        if(list!=null&list.size()>0){
            String destPath = environment.getProperty("pic.location.url");
            for(Map map:list){
                Map smap = new HashMap(8);
                String logoPath = null;
                //将链接url转换成图片
                String url = QRCodeUtil.encodeName(map.get("url").toString(), logoPath, destPath,  map.get("name").toString(), true);
                smap.put("name", map.get("name"));
                smap.put("url", url);
                picUrls.add(smap);

            }
            //将图片打包成zip并且导出去。
            downloadPic(response, picUrls);
        }
    }

    public void downloadPic(HttpServletResponse response, List<Map<String, String>> imgUrls) throws IOException {

        try {
            //文件的名称
            String downloadFilename = "channel.zip";
            //转换中文否则可能会产生乱码
            downloadFilename = URLEncoder.encode(downloadFilename, "UTF-8");
            // 指明response的返回对象是文件流
            response.setContentType("application/octet-stream");
            // 设置在下载框默认显示的文件名
            response.setHeader("Content-Disposition", "attachment;filename=" + downloadFilename);
            ZipOutputStream zos = new ZipOutputStream(response.getOutputStream());
            for (int i = 0; i < imgUrls.size(); i++) {
                Map<String, String> urlMap = imgUrls.get(i);
                zos.putNextEntry(new ZipEntry("二维码图片" + File.separator + urlMap.get("name") + ".jpg"));
                InputStream fis = getInputStreamByGet(urlMap.get("url"));
                byte[] buffer = new byte[1024];
                int r = 0;
                while ((r = fis.read(buffer)) != -1) {
                    zos.write(buffer, 0, r);
                }
                fis.close();
            }
            zos.flush();
            zos.close();
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

    public static InputStream getInputStreamByGet(String urlOrPath) throws IOException {
        File file = new File(urlOrPath);
        if (!file.isFile() || !file.exists() || !file.canRead()) {
            return null;
        }
        return new FileInputStream(file);
    }