java代碼解析二維碼一般步驟

本文采用的是google的zxing技術進行解析二維碼技術，解析二維碼的一般步驟如下：

一、下載zxing-core的jar包：

二、創建一個BufferedImageLuminanceSource類繼承LuminanceSource，此類在google的源碼中有，但是為了使用方便，下面有此類的源碼，可以直接復制使用：

	private final BufferedImage image;
	private final int left;
	private final int top;

	public BufferedImageLuminanceSource(BufferedImage image) {
		this(image, 0, 0, image.getWidth(), image.getHeight());
	}

	public BufferedImageLuminanceSource(BufferedImage image, int left, int top, int width, int height) {
		super(width, height);

		int sourceWidth = image.getWidth();
		int sourceHeight = image.getHeight();
		if (left + width > sourceWidth || top + height > sourceHeight) {
			throw new IllegalArgumentException("Crop rectangle does not fit within image data.");
		}

		for (int y = top; y < top + height; y++) {
			for (int x = left; x < left + width; x++) {
				if ((image.getRGB(x, y) & 0xFF000000) == 0) {
					image.setRGB(x, y, 0xFFFFFFFF); // = white
				}
			}
		}

		this.image = new BufferedImage(sourceWidth, sourceHeight, BufferedImage.TYPE_BYTE_GRAY);
		this.image.getGraphics().drawImage(image, 0, 0, null);
		this.left = left;
		this.top = top;
	}

	@Override
	public byte[] getRow(int y, byte[] row) {
		if (y < 0 || y >= getHeight()) {
			throw new IllegalArgumentException("Requested row is outside the image: " + y);
		}
		int width = getWidth();
		if (row == null || row.length < width) {
			row = new byte[width];
		}
		image.getRaster().getDataElements(left, top + y, width, 1, row);
		return row;
	}

	@Override
	public byte[] getMatrix() {
		int width = getWidth();
		int height = getHeight();
		int area = width * height;
		byte[] matrix = new byte[area];
		image.getRaster().getDataElements(left, top, width, height, matrix);
		return matrix;
	}

	@Override
	public boolean isCropSupported() {
		return true;
	}

	@Override
	public LuminanceSource crop(int left, int top, int width, int height) {
		return new BufferedImageLuminanceSource(image, this.left + left, this.top + top, width, height);
	}

	@Override
	public boolean isRotateSupported() {
		return true;
	}

	@Override
	public LuminanceSource rotateCounterClockwise() {

		int sourceWidth = image.getWidth();
		int sourceHeight = image.getHeight();

		AffineTransform transform = new AffineTransform(0.0, -1.0, 1.0, 0.0, 0.0, sourceWidth);

		BufferedImage rotatedImage = new BufferedImage(sourceHeight, sourceWidth, BufferedImage.TYPE_BYTE_GRAY);

		Graphics2D g = rotatedImage.createGraphics();
		g.drawImage(image, transform, null);
		g.dispose();

		int width = getWidth();
		return new BufferedImageLuminanceSource(rotatedImage, top, sourceWidth - (left + width), getHeight(), width);
	}

三、創建一個啟動類，用來解析二維碼：

	public static void main(String[] args) {
		try {
	        MultiFormatReader formatReader = new MultiFormatReader();
	        String filePath = "D:/test/博客.jpg";
	        File file = new File(filePath);
	        BufferedImage image = ImageIO.read(file);
	        LuminanceSource source = new BufferedImageLuminanceSource(image);
	        Binarizer  binarizer = new HybridBinarizer(source);
	        BinaryBitmap binaryBitmap = new BinaryBitmap(binarizer);
	        Map hints = new HashMap();
	        //解碼設置為UTF-8
	        hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
	        //優化精度
	        hints.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
	        //復雜模式，開啟PURE_BARCODE模式
	        hints.put(DecodeHintType.PURE_BARCODE, Boolean.TRUE);
	        Result result = formatReader.decode(binaryBitmap,hints);
	        System.out.println("result = "+ result.toString());
	        System.out.println("resultFormat = "+ result.getBarcodeFormat());
	        System.out.println("resultText = "+ result.getText());
	        
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

四、經過親自測試可以實現對二維碼的解析，可以獲取二維碼的url等信息；

java代碼解析二維碼