com.yupaits.yutool.file.core.DownloadTemplate Maven / Gradle / Ivy
package com.yupaits.yutool.file.core;
import com.google.common.net.HttpHeaders;
import com.yupaits.yutool.file.core.executor.IDownloadExecutor;
import com.yupaits.yutool.file.exception.DownloadException;
import com.yupaits.yutool.file.support.DownloadProps;
import com.yupaits.yutool.file.utils.WatermarkUtils;
import net.coobird.thumbnailator.Thumbnails;
import net.coobird.thumbnailator.filters.Watermark;
import org.apache.commons.io.FilenameUtils;
import org.springframework.http.MediaType;
import org.springframework.util.FileCopyUtils;
import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletResponse;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
/**
* 文件下载工具类
* @author yupaits
* @date 2019/7/22
*/
public class DownloadTemplate {
private final IDownloadExecutor downloadExecutor;
public DownloadTemplate(IDownloadExecutor downloadExecutor) {
this.downloadExecutor = downloadExecutor;
}
/**
* 下载文件
* @param response Response响应体
* @param fullPath fastdfs文件路径
* @throws IOException 抛出IOException
*/
public void downloadFile(HttpServletResponse response, String fullPath, DownloadProps downloadProps) throws IOException, DownloadException {
checkDownloadProps(downloadProps);
InputStream inputStream = downloadExecutor.downloadFile(fullPath);
if (downloadProps.isThumb() || downloadProps.isWithWatermark()) {
Thumbnails.Builder builder = Thumbnails.of(inputStream);
if (downloadProps.isThumb()) {
if (downloadProps.getWidth() > 0 && downloadProps.getHeight() > 0) {
builder.size(downloadProps.getWidth(), downloadProps.getHeight());
} else {
builder.scale(downloadProps.getScale());
}
builder.outputQuality(downloadProps.getQuality());
}
if (downloadProps.isWithWatermark()) {
BufferedImage bufferedImage;
switch (downloadProps.getWatermarkType()) {
case TEXT:
bufferedImage = WatermarkUtils.textToBufferedImage(downloadProps.getWatermarkText());
break;
case PICTURE:
bufferedImage = ImageIO.read(new File(downloadProps.getWatermarkPic()));
break;
default:
throw new DownloadException(String.format("不支持的图片水印类型，参数：%s", downloadProps.getWatermarkType()));
}
Watermark watermark = new Watermark(downloadProps.getWatermarkPos(), bufferedImage, downloadProps.getWatermarkOpacity());
builder.watermark(watermark);
if (!downloadProps.isThumb()) {
builder.scale(1.0);
}
}
sendFile(response, builder, FilenameUtils.getName(fullPath));
} else {
sendFile(response, inputStream, FilenameUtils.getName(fullPath));
}
}
/**
* 发送文件
* @param response Response响应体
* @param inputStream 输入流
* @param filename 文件名
*/
private void sendFile(HttpServletResponse response, InputStream inputStream, String filename) throws IOException {
response.setContentType(MediaType.APPLICATION_OCTET_STREAM_VALUE);
response.setHeader(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" +
URLEncoder.encode(filename, StandardCharsets.UTF_8.name())+ "\"");
FileCopyUtils.copy(inputStream, response.getOutputStream());
}
/**
* 发送文件
* @param response Response响应体
* @param builder ThumbnailBuilder
* @param filename 文件名
*/
private void sendFile(HttpServletResponse response, Thumbnails.Builder builder, String filename) throws IOException {
response.setContentType(MediaType.APPLICATION_OCTET_STREAM_VALUE);
response.setHeader(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" +
URLEncoder.encode(filename, StandardCharsets.UTF_8.name())+ "\"");
builder.toOutputStream(response.getOutputStream());
}
/**
* 校验DownloadProps参数
* @param downloadProps DownloadProps参数
*/
private void checkDownloadProps(DownloadProps downloadProps) throws DownloadException {
if (downloadProps == null || !downloadProps.isValid()) {
throw new DownloadException(String.format("下载配置校验失败，配置信息：%s", downloadProps));
}
}
}