二维码如何用Java语言生成
1.1首先引入对应的工具包。
<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>core</artifactId>
<version>3.3.3</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.10</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>javase</artifactId>
<version>3.3.3</version>
</dependency>
1.2 基础的图片生成类，没有时间研究，就照抄了
package com.nchu.common.core.utils.qrcode;
import com.google.zxing.LuminanceSource;
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
/**
* @Author LiuLaoLao
* @Date 2021/12/3 15:34
* @Version 1.0
*/
public class BufferedImageLuminanceSource extends LuminanceSource {
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);
}
}
1.3 二维码生成的工具类
/**
* @Author LiuLaoLao
* @Date 2021/12/3 15:34
* @Version 1.0
*/
@Slf4j
public class QRCodeUtil {
/**
* 创建二维码
* @param charSet 编码方式
* @param content 二维码内容
* @param qrWidth 二维码长度
* @param qrHeight 二维码高度
* @return
*/
public static BufferedImage createImage(String charSet,String content,int qrWidth,int qrHeight){
Hashtable hints = new Hashtable();
hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
hints.put(EncodeHintType.CHARACTER_SET, charSet);
hints.put(EncodeHintType.MARGIN, 1);
BitMatrix bitMatrix = null;
try {
bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE,qrWidth , qrHeight, // 修改二维码底部高度
hints);
} catch (WriterException e) {
e.printStackTrace();
}
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);
}
}
return image;
}
/**
* 对已经生成好的二维码设置logo
* @param source 二维码
* @param logo logo图片
* @param logoWidth logo宽度
* @param logoHeight logo高度
*/
public static void insertLogoImage(BufferedImage source,Image logo,int logoWidth,int logoHeight){
Graphics2D graph = source.createGraphics();
int qrWidth = source.getWidth();
int qrHeight = source.getHeight();
int x = (qrWidth - logoWidth) / 2;
int y = (qrHeight - logoHeight) / 2;
graph.drawImage(logo, x, y, logoWidth, logoHeight, null);
Shape shape = new RoundRectangle2D.Float(x, y, logoWidth, logoHeight, 6, 6);
graph.setStroke(new BasicStroke(3f));
graph.draw(shape);
graph.dispose();
}
/**
* 缩小logo图片
* @param logoPath
* @param logoWidth
* @param logoHeight
* @return
*/
public static Image compressLogo(String logoPath, int logoWidth, int logoHeight){
File file = new File(logoPath);
if (!file.exists()) {
System.err.println("" + logoPath + " 该文件不存在！");
return null;
}
Image original = null;
try {
original = ImageIO.read(new File(logoPath));
} catch (IOException e) {
e.printStackTrace();
}
int width = original.getWidth(null);
int height = original.getHeight(null);
if (width > logoWidth) {
width = logoWidth;
}
if (height > logoHeight) {
height = logoHeight;
}
Image image = original.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();
return image;
}
/**
* 增加底部的说明文字
* @param source 二维码
* @param text 说明内容
* @param step
*/
public static BufferedImage addBottomFont(BufferedImage source, String text,int step) {
int qrWidth = source.getWidth();
log.debug("二维码的宽度{}",qrWidth);
int qrHeight = source.getHeight();
log.debug("二维码的高度{}",qrHeight);
BufferedImage textImage = textToImage(text, qrWidth, 20,16);
Graphics2D graph = source.createGraphics();
//开启文字抗锯齿
graph.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
int width = textImage.getWidth(null);
int height = textImage.getHeight(null);
Image src = textImage;
graph.drawImage(src, 0, qrHeight - (20 * step) - 10, width, height, null);
graph.dispose();
return source;
}
/**
* 将文明说明增加到二维码上
* @param str
* @param width
* @param height
* @param fontSize 字体大小
* @return
*/
public static BufferedImage textToImage(String str, int width, int height,int fontSize) {
BufferedImage textImage = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = (Graphics2D)textImage.getGraphics();
//开启文字抗锯齿
g2.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
g2.setBackground(Color.WHITE);
g2.clearRect(0, 0, width, height);
g2.setPaint(Color.BLACK);
FontRenderContext context = g2.getFontRenderContext();
Font font = new Font("微软雅黑", Font.BOLD, fontSize);
g2.setFont(font);
LineMetrics lineMetrics = font.getLineMetrics(str, context);
FontMetrics fontMetrics = FontDesignMetrics.getMetrics(font);
float offset = (width - fontMetrics.stringWidth(str)) / 2;
float y = (height + lineMetrics.getAscent() - lineMetrics.getDescent() - lineMetrics.getLeading()) / 2;
g2.drawString(str, (int)offset, (int)y);
return textImage;
}
/**
* 顶部增加说明文字
* @param source
* @param text
* @param step
*/
public static void addUpFont(BufferedImage source, String text) {
int qrWidth = source.getWidth();
int qrHeight = source.getHeight();
BufferedImage textImage = textToImage(text, qrWidth, 30,24);
Graphics2D graph = source.createGraphics();
//开启文字抗锯齿
graph.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
int width = textImage.getWidth(null);
int height = textImage.getHeight(null);
Image src = textImage;
graph.drawImage(src, 0, 30, width, height, null);
graph.dispose();
}
/**
* 生成二维码图片
* @param charSet 二维码编码方式
* @param content 内容
* @param qrWidth 宽度
* @param qrHeight 长度
* @param formatName jpg等图片格式
* @param imgPath 二维码存放路径
*/
public static void encode(String charSet,String content,int qrWidth,int qrHeight,String formatName,String imgPath){
BufferedImage image = QRCodeUtil.createImage(charSet,content,qrWidth,qrHeight);
try {
ImageIO.write(image, formatName, new File(imgPath));
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 生成二维码图片流
* @param charSet 二维码编码方式
* @param content 内容
* @param qrWidth 宽度
* @param qrHeight 长度
* @return
*/
public static BufferedImage encode(String charSet,String content,int qrWidth,int qrHeight) {
BufferedImage image = QRCodeUtil.createImage(charSet,content,qrWidth,qrHeight);
return image;
}
public static void encode( BufferedImage image,String formatName,String imgPath){
try {
ImageIO.write(image, formatName, new File(imgPath));
} catch (IOException e) {
e.printStackTrace();
}
}
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();
}
}
/*
* 解析二维码
*/
public static String decode(File file,String cherSet) 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 hints = new Hashtable();
hints.put(DecodeHintType.CHARACTER_SET, cherSet);
result = new MultiFormatReader().decode(bitmap, hints);
String resultStr = result.getText();
return resultStr;
}
}
全部评论