近期做的一個專案，其中有一個批量生成一維碼，然後將多個一維碼放到一個圖片輸出的功能。自己做了一個小Demo，在這裡記錄一下。

生成一維碼的功能使用的是barcode，一下是程式碼，程式碼很簡單,就一下帖處理，不在每塊做詳細描述了：

import com.google.common.collect.Lists;
import org.krysalis.barcode4j.HumanReadablePlacement;
import org.krysalis.barcode4j.impl.code39.Code39Bean;
import org.krysalis.barcode4j.output.bitmap.BitmapCanvasProvider;
import
 
 org.krysalis.barcode4j.tools.UnitConv;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.*;
import java.util.List;

/**
 * 在這裡編寫類的功能描述
 *
 * @author yangbin
 * @created 2017/6/20
 */
public class BarCodeTest {

    static String FILE_PATH = "/tmp/barcode/"
 
;

    static int clowns = 5;
    /**
     * 行間距
     */
    static int LineSpacing = 20;


    public static void main(String[] args) {


        int code = 1234567890;
        List<String> barCodeFileNames = Lists.newArrayList();
        //需要生成的一維碼code
        for(int i=0;i<10;i++) {
            String barCode = (code + i) + ""
 
;
            barCodeFileNames.add(generateImg(barCode));
        }
        System.out.println(barCodeFileNames);
        //講多個一維碼合成到一個圖片上
        boolean result = mergeImg(barCodeFileNames, FILE_PATH+Thread.currentThread().getName() + System.currentTimeMillis() + ".png");

        System.out.println(result);

    }

    /**
     * 合併圖片
     * @param barCodeFileNames
     * @param imgName
     * @return
     */
    public static boolean mergeImg(List<String> barCodeFileNames,String imgName) {
        int size = barCodeFileNames.size();
        File[] barCodeFiles = new File[size];
        BufferedImage[] bufferedImages = new BufferedImage[size];
        for(int i = 0;i<size;i++) {
            try {
                barCodeFiles[i] = new File(barCodeFileNames.get(i));
                bufferedImages[i] = ImageIO.read(barCodeFiles[i]);
            } catch (IOException e) {
                e.printStackTrace();
                return false;
            }
        }

        int singleImgWidth = bufferedImages[0].getWidth();
        int singleImgHeight = bufferedImages[0].getHeight();

        int rows = size % clowns == 0 ? size / clowns : (size / clowns + 1);

        int combinImgWidth = singleImgWidth * clowns ;


        int combinImgHeight = singleImgHeight * rows + LineSpacing * rows;
        try {
            //合成圖
            BufferedImage combinedImg = new BufferedImage(combinImgWidth, combinImgHeight, BufferedImage.TYPE_INT_RGB);
            Graphics2D g2 = (Graphics2D) combinedImg.getGraphics();
            //設定背景色為白色，預設為黑色
            g2.setBackground(Color.WHITE);
            g2.clearRect(0, 0, combinImgWidth, combinImgHeight);


            for(int i = 0;i<size;i++) {
                int startX = (i % clowns) * singleImgWidth;
                int startY = (i / clowns) * (singleImgHeight + LineSpacing);

                int[] imageRGB = new int[singleImgWidth * singleImgHeight];
                imageRGB = bufferedImages[i].getRGB(0, 0, singleImgWidth, singleImgHeight,imageRGB, 0, singleImgWidth);
                //講單個圖片的RGB值寫入合成圖中
                combinedImg.setRGB(startX, startY, singleImgWidth, singleImgHeight, imageRGB, 0, singleImgWidth);

            }

            File outFile = new File(imgName);

            ImageIO.write(combinedImg, "png", outFile);

        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
        //清理單個圖片
        for(int i = 0;i<size;i++) {
            barCodeFiles[i].delete();
        }

        return true;
    }


    /**
     * 生成二維碼
     * @param barcode
     * @return
     */
    public static String generateImg(String barcode) {
        OutputStream out = null;
        String fileName = null;
        try {
            Code39Bean bean = new Code39Bean();
            final int dpi = 150;
            bean.setModuleWidth(UnitConv.in2mm(1.0f / dpi));
            // 寬度
            bean.setWideFactor(4);
            // 高度
            bean.setHeight(10);
            // 條形碼左右兩邊是否留空白，預設為true
            bean.doQuietZone(true);
            // 設定條碼號字型的大小
            bean.setFontSize(3);
            // 設定條碼號顯示的位置
            bean.setMsgPosition(HumanReadablePlacement.HRP_BOTTOM);
            // 獲取檔案的儲存位置
            fileName = FILE_PATH + barcode + ".png";
            File outputFile = new File(fileName);
            out = new FileOutputStream(outputFile);
            BitmapCanvasProvider canvas = new BitmapCanvasProvider(out, "image/png", dpi,
                    BufferedImage.TYPE_BYTE_BINARY, false, 0);
            bean.generateBarcode(canvas, barcode);
            canvas.finish();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            return null;
        } catch (IOException e) {
            e.printStackTrace();
            return null;
        } finally {
            try {
                out.flush();
                out.close();
            } catch (IOException e) {
                e.printStackTrace();
                return null;
            }
        }
        return fileName;
    }
}