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Java后台生成二维码

發布時間：2024/1/18 java 24 豆豆

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今天做了一下生成二維碼的兩種方式
第一種就是前臺調用接口去生成二維碼，第二種就是后臺生成二維碼
既然我們是后臺開發人員，我這里就寫后臺代碼了，后臺代碼實現很簡單，說白了大家調用一個工具類就OK啦。
工具類只需要繼承LuminanceSource類，重寫其中的方法，話不多說上代碼。
package com.zx.controller;

import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Map;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletResponse;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.Binarizer;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.EncodeHintType;
import com.google.zxing.LuminanceSource;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.Result;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

/**

Title:QRCodeUtil
Description: 二維碼生成工具類
@author Administrator
@version
@since
*/
public final class QRCodeUtil extends LuminanceSource {

private static final Logger logger = LoggerFactory.getLogger(QRCodeUtil.class);

// 二維碼顏色
private static final int BLACK = 0xFF000000;
// 二維碼顏色
private static final int WHITE = 0xFFFFFFFF;

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

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

public QRCodeUtil(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 QRCodeUtil(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 QRCodeUtil(rotatedImage, top, sourceWidth - (left + width), getHeight(), width);
}

/**
- @param matrix
- @return
  */
  private static BufferedImage toBufferedImage(BitMatrix matrix) {
  int width = matrix.getWidth();
  int height = matrix.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, matrix.get(x, y) ? BLACK : WHITE);
  }
  }
  return image;
  }
/**
- 生成二維碼圖片
- @param matrix
- @param format
- @param file
- @throws IOException
  */
  public static void writeToFile(BitMatrix matrix, String format, File file) throws IOException {
  BufferedImage image = toBufferedImage(matrix);
  if (!ImageIO.write(image, format, file)) {
  throw new IOException("Could not write an image of format " + format + " to " + file);
  }
  }
/**
- 生成二維碼圖片流
- @param matrix
- @param format
- @param stream
- @throws IOException
  */
  public static void writeToStream(BitMatrix matrix, String format, OutputStream stream) throws IOException {
  BufferedImage image = toBufferedImage(matrix);
  if (!ImageIO.write(image, format, stream)) {
  throw new IOException("Could not write an image of format " + format);
  }
  }
/**
- 根據內容，生成指定寬高、指定格式的二維碼圖片
- @param text 內容
- @param width 寬
- @param height 高
- @param format 圖片格式
- @return 生成的二維碼圖片路徑
- @throws Exception
  */
  private static String generateQRCode(String text, int width, int height, String format, String pathName)
  throws Exception {
  Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
  hints.put(EncodeHintType.CHARACTER_SET, “utf-8”);// 指定編碼格式
  hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.L);// 指定糾錯等級
  hints.put(EncodeHintType.MARGIN, 1); // 白邊大小，取值范圍0~4
  BitMatrix bitMatrix = new MultiFormatWriter().encode(text, BarcodeFormat.QR_CODE, width, height, hints);
  File outputFile = new File(pathName);
  writeToFile(bitMatrix, format, outputFile);
  return pathName;
  }
/**
- 輸出二維碼圖片流
- @param text 二維碼內容
- @param width 二維碼寬
- @param height 二維碼高
- @param format 圖片格式eg: png, jpg, gif
- @param response HttpServletResponse
- @throws Exception
  */
  public static void generateQRCode(String text, int width, int height, String format, HttpServletResponse response)
  throws Exception {
  Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
  hints.put(EncodeHintType.CHARACTER_SET, “utf-8”);// 指定編碼格式
  hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.L);// 指定糾錯等級
  hints.put(EncodeHintType.MARGIN, 1); // 白邊大小，取值范圍0~4
  BitMatrix bitMatrix = new MultiFormatWriter().encode(text, BarcodeFormat.QR_CODE, width, height, hints);
  writeToStream(bitMatrix, format, response.getOutputStream());
  }
/**
- 解析指定路徑下的二維碼圖片
- @param filePath 二維碼圖片路徑
- @return
  */
  public static String parseQRCode(String filePath) {
  String content = “”;
  try {
  File file = new File(filePath);
  BufferedImage image = ImageIO.read(file);
  LuminanceSource source = new QRCodeUtil(image);
  Binarizer binarizer = new HybridBinarizer(source);
  BinaryBitmap binaryBitmap = new BinaryBitmap(binarizer);
  Map<DecodeHintType, Object> hints = new HashMap<DecodeHintType, Object>();
  hints.put(DecodeHintType.CHARACTER_SET, “UTF-8”);
  MultiFormatReader formatReader = new MultiFormatReader();
  Result result = formatReader.decode(binaryBitmap, hints);
  logger.info("result 為：" + result.toString());logger.info("resultFormat 為：" + result.getBarcodeFormat());logger.info("resultText 為：" + result.getText());// 設置返回值content = result.getText();
  } catch (Exception e) {
  logger.error(e.getMessage());
  }
  return content;
  }
public static void main(String[] args) {
String text = “hello world!”; // 隨機生成驗證碼
System.out.println("隨機碼： " + text);
int width = 100; // 二維碼圖片的寬
int height = 100; // 二維碼圖片的高
String format = “png”; // 二維碼圖片的格式
try {// 生成二維碼圖片，并返回圖片路徑String pathName = generateQRCode(text, width, height, format, "D:/new.png");System.out.println("生成二維碼的圖片路徑： " + pathName);String content = parseQRCode(pathName);System.out.println("解析出二維碼的圖片的內容為： " + content);} catch (Exception e) {e.printStackTrace();}
}

}

main方法直接運行，會在你的d盤生成一個png文件，二維碼自動生成，內容就寫到text里面就可以，是不是很簡單。
就說這么多啦，大家自己消化一下吧。

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