我们在开发的时候,肯定有这样的需求。把一个url链接转成二维码图片。提供给用户扫描,然后跳转到相应的页面。
三个问题(前提:没有用统一的图片服务器如:fastdfs。)
(1):把url链接转成图片保存。这样只需要提供图片的地址就行。
(2):但是有的时候,需要提供base64图片流。这是因为,图片可能是在内网,不能通过ip转到外面。
(3):当使用分布式服务器的时候,生成的图片的地址不一样,如果查找的时候,就不利于管理。这个时候,可以用不需要生成图片的方式。
(1):需要使用生成二维码的jar包。zxing是比较通用的jar包。
com.google.zxing
core
3.3.0
com.google.zxing
javase
3.3.0
(2):编写生成二维码的util.也就是Qrcode.util
package com.iflytek.util;
import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Shape;
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;
import javax.imageio.ImageIO;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.Result;
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;
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 hints = new Hashtable();
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;
}
/**
* 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 hints = new Hashtable();
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 hints = new Hashtable();
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;
}
public static void main(String[] args) throws Exception {
String text = "https://www.yoyow.org/files/d2b3b82351bda9e70b92c6ee219a432b.png"; //这里设置自定义网站url
String logoPath =null;
String destPath = "d:\\pic\\";
String url=QRCodeUtil.encode(text, logoPath, destPath, true);
System.out.println(url);
/* String file="D:\\11.jpg";
String info=QRCodeUtil.decode(file);
System.out.println(info);*/
}
}
使用QRCodeUtil.encode("url链接地址","logo的地址","生成的图片放在的位置(jpg图片的物理地址如:opt/项目名/jpg/)")。
(3):访问生成的图片,需要在一个config即MvcConfig
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.env.Environment;
import org.springframework.web.filter.CommonsRequestLoggingFilter;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
@Configuration
public class MvcConfig extends WebMvcConfigurerAdapter {
private static Logger logger= LoggerFactory.getLogger(MvcConfig.class);
@Autowired
private Environment environment;
/**
*图片等地址映射
* @param registry
*/
@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
logger.info("pdfURL="+environment.getProperty("qr.location.url"));
registry.addResourceHandler("/pdf/**").addResourceLocations("file:"+environment.getProperty("qr.location.url"));
registry.addResourceHandler("/excel/**").addResourceLocations("file:"+environment.getProperty("excel.location.url"));
super.addResourceHandlers(registry);
}
@Bean
public CommonsRequestLoggingFilter requestLoggingFilter() {
CommonsRequestLoggingFilter loggingFilter = new CommonsRequestLoggingFilter();
loggingFilter.setMaxPayloadLength(2048);
loggingFilter.setIncludeClientInfo(true);
loggingFilter.setIncludeQueryString(true);
loggingFilter.setIncludePayload(true);
loggingFilter.setIncludeHeaders(true);
return loggingFilter;
}
@Override
public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
configurer.enable();
}
}
(4):在配置文件application.properties
#生成二维码物理地址
qr.location.url=D:/mnt/hmzhao/analytics/pic/
这样生成的图片就可以通过
ip+port+项目名称+/pdf/+生成图片名称+.jpg
如:http://192.168.171.219:8088/test/pdf/12345.jpg
解决了第一个问题。第二个问题就稍微简单些,只需要把生成的图片转成base64流就可以。
(1):将图片流转换成base64流的util.PicBaseUtil.java
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
import sun.misc.BASE64Encoder;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
public class PicBaseUtil {
/**
* 将本地图片转换成Base64编码字符串
*
* @param imgFile 图片目录路径
* @return
*/
public String getImgFileToBase64(String imgFile) {
//将图片文件转化为字节数组字符串,并对其进行Base64编码处理
InputStream inputStream = null;
byte[] buffer = null;
//读取图片字节数组
try {
inputStream = new FileInputStream(imgFile);
int count = 0;
while (count == 0) {
count = inputStream.available();
}
buffer = new byte[count];
inputStream.read(buffer);
} catch (IOException e) {
e.printStackTrace();
} finally {
if (inputStream != null) {
try {
// 关闭inputStream流
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
// 对字节数组Base64编码
return new BASE64Encoder().encode(buffer);
}
}
(2):由于第一个问题中生成的图片放在一个物理地址上,所以,第二个问题需要第一个问题的物理地址。
String localPic="图片的物理地址";
String base= (new PicBaseUtil()).getImgFileToBase64(localPic);
这样返回的base64就是提供给前端的base64流。
解决第三个问题,不需要使用第一,第二个问题的结果,直接调用方法就可以生成了。
(1)转换的代码块
/**
* 将图片url转换成base64流
* @param url
* @return
*/
public String getBase64(String url){
MultiFormatWriter multiFormatWriter = new MultiFormatWriter();
Map hints = new HashMap();
hints.put(EncodeHintType.CHARACTER_SET, "UTF-8"); //设置字符集编码类型
hints.put(EncodeHintType.MARGIN, 1); //设置白边
BitMatrix bitMatrix = null;
try {
bitMatrix = multiFormatWriter.encode(url, BarcodeFormat.QR_CODE, 300, 300,hints);
BufferedImage image = toBufferedImage(bitMatrix);
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
//输出二维码图片流
try {
ImageIO.write(image, "jpg",outputStream);
String base =new BASE64Encoder().encode(outputStream.toByteArray());
return base;
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (WriterException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
return null;
}
public 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) ? 0xFF000000 : 0xFFFFFFFF);//0xFF000000黑;0xFFFFFFFF白
}
}
return image;
}
(2):使用方法。直接将url链接转成base64流。
String url="url链接";
String base= (new PicBaseUtil()).getBase64(url);
这样返回的base64就是提供给前端的base64流。
参考:Java通过图片url地址获取图片base64位字符串的两种方式