top.lshaci.framework.web.utils.DownloadUtils Maven / Gradle / Ivy

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package top.lshaci.framework.web.utils;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URLEncoder;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.lang3.StringUtils;

import lombok.extern.slf4j.Slf4j;
import top.lshaci.framework.common.exception.BaseException;
import top.lshaci.framework.utils.StreamUtils;
import top.lshaci.framework.web.enums.ResponseContentType;
import top.lshaci.framework.web.exception.WebBaseException;

/**
 * Download utils


 *
 * 1.0.2: 删除cache size配置，使用默认的2048
 * @author lshaci
 * @since 0.0.4
 * @version 1.0.2
 */
@Slf4j
public class DownloadUtils {

	/**
     * Download file
     *
     * @param downloadName the download file name(Must include suffixes)
     * @param contentType the http servlet response content type
     * @param outputStream the byte array output stream of the file
     * @param response the http servlet response
     */
    public static void download(String downloadName, ResponseContentType contentType,
            ByteArrayOutputStream outputStream, HttpServletResponse response) {
        try (
                InputStream is = new ByteArrayInputStream(outputStream.toByteArray());
                ServletOutputStream os = response.getOutputStream()
        ) {
            writeFile(downloadName, contentType, response, is, os);
        } catch (Exception e) {
            log.error("导出[" + downloadName + "]失败", e);
            throw new WebBaseException("导出[" + downloadName + "]失败", e);
        }
    }

    /**
     * Download file
     *
     * @param downloadName the download file name(Must include suffixes)
     * @param contentType the http servlet response content type
     * @param is the file input stream
     * @param response the http servlet response
     */
    public static void download(String downloadName, ResponseContentType contentType,
            FileInputStream is, HttpServletResponse response) {
        try (
                ServletOutputStream os = response.getOutputStream()
        ) {
            writeFile(downloadName, contentType, response, is, os);
        } catch (Exception e) {
            log.error("导出[" + downloadName + "]失败", e);
            throw new WebBaseException("导出[" + downloadName + "]失败", e);
        }
    }

    /**
     * Download file
     *
     * @param downloadName the download file name(Must include suffixes)
     * @param contentType the http servlet response content type
     * @param filePath the path of the file
     * @param response the http servlet response
     */
    public static void download(String downloadName, ResponseContentType contentType,
            String filePath, HttpServletResponse response) {
        try (
                InputStream is = new FileInputStream(filePath);
                ServletOutputStream os = response.getOutputStream()
        ) {
            writeFile(downloadName, contentType, response, is, os);
        } catch (Exception e) {
            log.error("导出[" + downloadName + "]失败", e);
            throw new WebBaseException("导出[" + downloadName + "]失败", e);
        }
    }

    /**
     * Write out file
     *
     * @param downloadName the download file name
     * @param contentType the http servlet response content type
     * @param response the http servlet response
     * @param is the input stream of the file
     * @param os the servlet output stream
     * @throws IOException
     */
    private static void writeFile(String downloadName, ResponseContentType contentType,
            HttpServletResponse response, InputStream is, ServletOutputStream os) throws IOException {
        response.setHeader("Content-disposition", "attachment;filename=" + URLEncoder.encode(downloadName, "UTF-8"));
        if (StringUtils.isBlank(downloadName)) {
            throw new BaseException("The download file name must not be empty!");
        }
        if (contentType != null) {
            response.setContentType(contentType.getName());
        }
        
        StreamUtils.write(is, os);
    }
}