** 2019-12-05 17:19:50 **
今天改需求看到之前写的zxing二维码，记录一下。
Maven仓库
<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>core</artifactId>
<version>3.2.1</version>
</dependency>
<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>javase</artifactId>
<version>3.0.0</version>
</dependency>
简单下载单张
/**
* 下载二维码
*
* @param roomId 二维码中存放的的数据
* @param request
* @param response
* @throws IOException
*/
@GetMapping("/code/download/{roomId}")
@ApiOperation("二维码下载")
public void downloadCode(@PathVariable String roomId, HttpServletRequest request, HttpServletResponse response) throws IOException {
if (roomId == null) {
return;
}
// ---------加密内容------------
// log.info("------------>要加密的数据roomId:{}", roomId);
String content = Base64.getEncoder().encodeToString(roomId.toString().getBytes("UTF-8"));
if (content != null && !"".equals(content)) {
// ----------二维码设置----------
// 图像宽度
int width = 300;
// 图像高度
int height = 300;
// 图像类型
String format = "png";
Map<EncodeHintType, Object> hints = new HashMap<EncodeHintType, Object>(3);
// 编码格式
hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
// 设置容错等级
hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M);
// 设置边距默认是5
hints.put(EncodeHintType.MARGIN, 2);
BitMatrix bitMatrix = null;
OutputStream outputStream = null;
InputStream inputStream = null;
try {
bitMatrix = new QRCodeWriter().encode(content, BarcodeFormat.QR_CODE, width, height, hints);
BufferedImage image = MatrixToImageWriter.toBufferedImage(bitMatrix);
// 二维码图片转化成字节数组
ByteArrayOutputStream out = new ByteArrayOutputStream();
boolean write = ImageIO.write(image, format, out);
inputStream = new ByteArrayInputStream(out.toByteArray());
outputStream = response.getOutputStream();
response.reset();
// 设置文件头编码方式和文件名
String date = LocalDate.now().toString();
String fileName = "二维码" + date + ".png";
response.setCharacterEncoding("UTF-8");
// 如果是IE,通过URLEncoder对filename进行UTF8编码。而其他的浏览器（firefox、chrome、safari、opera），则要通过字节转换成ISO8859-1。
if (request.getHeader("User-Agent").toUpperCase().indexOf("MSIE") > 0) {
fileName = URLEncoder.encode(fileName, "UTF-8");
} else {
fileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1");
}
response.setContentType("application/octet-stream");
response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
byte[] bf = new byte[1024];
int len = 0;
while ((len = inputStream.read(bf)) > 0) {
outputStream.write(bf, 0, len);
}
} catch (WriterException e) {
e.printStackTrace();
} finally {
if (outputStream != null) {
outputStream.flush();
outputStream.close();
}
if (inputStream != null) {
inputStream.close();
}
}
}
}
注意
一般项目中请求接口需要带token的，下载时如果是直接请求下载接口，需要暴露接口。在配置文件中暴露
下载多个二维码，打包.zip包
/**
* 获取到宿舍dormId --下载二维码zip包
*
* @param dormId 业务查询的楼栋id
* @param request
* @param response
* @return
* @throws IOException
*/
@GetMapping("/download/{dormId}")
@ApiOperation("二维码下载")
public R downloadCode(@PathVariable String dormId, HttpServletRequest request, HttpServletResponse response) throws IOException {
try {
Dormitory dormitory=dormitoryService.getById(dormId);
//按宿舍楼id查询所有宿舍
List<Room> roomIdList = roomService.getbyDormIdRoomAll(dormId);
//按宿舍楼id查询所有床位
List<Bunk> bunkList = bunkService.getByDormIdBunkAll(dormId);
String realPath = request.getSession().getServletContext().getRealPath("/");
//1 生成二维码
String path = realPath + dormitory.getTowerName();
File file = new File(path);
if (!file.exists()) {
file.mkdirs();
}
///////////////每条线程的数据数量
int threadSize = 200;
// 总数据条数
int dataSize2=bunkList.size();
// 线程数
int threadNum = dataSize2 / threadSize + 1;
// 定义标记,过滤threadNum为整数
boolean special = dataSize2 % threadSize == 0;
// 创建一个线程池
ExecutorService exec = Executors.newFixedThreadPool(threadNum);
// 定义一个任务集合
List<Callable<Integer>> tasks = new ArrayList<Callable<Integer>>();
Callable<Integer> task = null;
List<Bunk> bunkCall = null;
///////////////////////
// 确定每条线程的数据
for (int i = 0; i < threadNum; i++) {
if (i == threadNum - 1) {
if (special) {
break;
}
bunkCall = bunkList.subList(threadSize * i, dataSize2);
} else {
bunkCall = bunkList.subList(threadSize * i, threadSize * (i + 1));
}
final List<Bunk> bunkListStr = bunkCall;
task = new Callable<Integer>() {
Integer count = 0;
@Override
public Integer call() throws Exception {
for (Bunk bunk : bunkListStr) {
QRCodeUtil.generateQRImage(
InspectionConstant.inspectionType.DORM_BED.toString() + "|" + bunk.getId(),
path + "/" + bunk.getRoomId() + "号宿舍" + bunk.getNumber() + "床位" + ".jpg",
null,bunk.getNumber()
);//生成二维码的方法
}
count++;
return 1;
}
};
// 这里提交的任务容器列表和返回的Future列表存在顺序对应的关系
tasks.add(task);
}
//生成二维码
QRCodeUtil.generateQRImage(
InspectionConstant.inspectionType.DORM_TOWER.toString() + "|" + dormId,
path + "/宿舍楼" + dormitory.getTowerName() + ".jpg",
null,dormitory.getTowerName());
for (Room x : roomIdList) {
//生成二维码的方法
QRCodeUtil.generateQRImage(
InspectionConstant.inspectionType.DORM_ROOM.toString() + "|" + x.getId(),
path + "/宿舍" + x.getNumber() + ".jpg",
null,x.getNumber()
);
}
//开始执行线程任务
List<Future<Integer>> results = exec.invokeAll(tasks);
// 关闭线程池
exec.shutdown();
//2 生成zip文件
ZipHelper.zipCompress(path, path + ".zip");
//3 下载
String zipFileName = path + ".zip";
String filename = dormitory.getTowerName()+ ".zip";
//设置文件MIME类型
response.setContentType("application/octet-stream");
response.setCharacterEncoding("UTF-8");
//设置Content-Disposition
response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(filename, "utf-8"));
InputStream in = new FileInputStream(zipFileName);
OutputStream out = response.getOutputStream();
//写文件
int b;
while ((b = in.read()) != -1) {
out.write(b);
}
out.flush();
//4 删除多余文件
ZipHelper.deleteDir(new File(path));
in.close();//先关闭输入流才能删除
ZipHelper.deleteDir(new File(zipFileName));
out.close();
} catch (Exception e) {
R.failed("下载二维码错误"+e);
e.printStackTrace();
}
return null;
}
