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+package org.jeecg.modules.erp.utils;
+
+import java.io.*;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import org.apache.commons.io.IOUtils;
+import org.apache.commons.lang3.ArrayUtils;
+import org.apache.commons.io.FilenameUtils;
+
+/**
+ * 文件处理工具类
+ * 
+ * @author ruoyi
+ */
+public class FileUtils
+{
+    public static String FILENAME_PATTERN = "[a-zA-Z0-9_\\-\\|\\.\\u4e00-\\u9fa5]+";
+
+    /**
+     * 输出指定文件的byte数组
+     * 
+     * @param filePath 文件路径
+     * @param os 输出流
+     * @return
+     */
+    public static void writeBytes(String filePath, OutputStream os) throws IOException
+    {
+        FileInputStream fis = null;
+        try
+        {
+            File file = new File(filePath);
+            if (!file.exists())
+            {
+                throw new FileNotFoundException(filePath);
+            }
+            fis = new FileInputStream(file);
+            byte[] b = new byte[1024];
+            int length;
+            while ((length = fis.read(b)) > 0)
+            {
+                os.write(b, 0, length);
+            }
+        }
+        catch (IOException e)
+        {
+            throw e;
+        }
+        finally
+        {
+            os.close();
+            fis.close();
+        }
+    }
+
+
+
+    /**
+     * 删除文件
+     * 
+     * @param filePath 文件
+     * @return
+     */
+    public static boolean deleteFile(String filePath)
+    {
+        boolean flag = false;
+        File file = new File(filePath);
+        // 路径为文件且不为空则进行删除
+        if (file.isFile() && file.exists())
+        {
+            flag = file.delete();
+        }
+        return flag;
+    }
+
+    /**
+     * 文件名称验证
+     * 
+     * @param filename 文件名称
+     * @return true 正常 false 非法
+     */
+    public static boolean isValidFilename(String filename)
+    {
+        return filename.matches(FILENAME_PATTERN);
+    }
+
+
+    /**
+     * 下载文件名重新编码
+     * 
+     * @param request 请求对象
+     * @param fileName 文件名
+     * @return 编码后的文件名
+     */
+    public static String setFileDownloadHeader(HttpServletRequest request, String fileName) throws UnsupportedEncodingException
+    {
+        final String agent = request.getHeader("USER-AGENT");
+        String filename = fileName;
+        if (agent.contains("MSIE"))
+        {
+            // IE浏览器
+            filename = URLEncoder.encode(filename, "utf-8");
+            filename = filename.replace("+", " ");
+        }
+        else if (agent.contains("Firefox"))
+        {
+            // 火狐浏览器
+            filename = new String(fileName.getBytes(), "ISO8859-1");
+        }
+        else if (agent.contains("Chrome"))
+        {
+            // google浏览器
+            filename = URLEncoder.encode(filename, "utf-8");
+        }
+        else
+        {
+            // 其它浏览器
+            filename = URLEncoder.encode(filename, "utf-8");
+        }
+        return filename;
+    }
+
+    /**
+     * 下载文件名重新编码
+     *
+     * @param response 响应对象
+     * @param realFileName 真实文件名
+     */
+    public static void setAttachmentResponseHeader(HttpServletResponse response, String realFileName) throws UnsupportedEncodingException
+    {
+        String percentEncodedFileName = percentEncode(realFileName);
+
+        StringBuilder contentDispositionValue = new StringBuilder();
+        contentDispositionValue.append("attachment; filename=")
+                .append(percentEncodedFileName)
+                .append(";")
+                .append("filename*=")
+                .append("utf-8''")
+                .append(percentEncodedFileName);
+
+        response.addHeader("Access-Control-Expose-Headers", "Content-Disposition,download-filename");
+        response.setHeader("Content-disposition", contentDispositionValue.toString());
+        response.setHeader("download-filename", percentEncodedFileName);
+    }
+
+    /**
+     * 百分号编码工具方法
+     *
+     * @param s 需要百分号编码的字符串
+     * @return 百分号编码后的字符串
+     */
+    public static String percentEncode(String s) throws UnsupportedEncodingException
+    {
+        String encode = URLEncoder.encode(s, StandardCharsets.UTF_8.toString());
+        return encode.replaceAll("\\+", "%20");
+    }
+
+    /**
+     * 获取图像后缀
+     * 
+     * @param photoByte 图像数据
+     * @return 后缀名
+     */
+    public static String getFileExtendName(byte[] photoByte)
+    {
+        String strFileExtendName = "jpg";
+        if ((photoByte[0] == 71) && (photoByte[1] == 73) && (photoByte[2] == 70) && (photoByte[3] == 56)
+                && ((photoByte[4] == 55) || (photoByte[4] == 57)) && (photoByte[5] == 97))
+        {
+            strFileExtendName = "gif";
+        }
+        else if ((photoByte[6] == 74) && (photoByte[7] == 70) && (photoByte[8] == 73) && (photoByte[9] == 70))
+        {
+            strFileExtendName = "jpg";
+        }
+        else if ((photoByte[0] == 66) && (photoByte[1] == 77))
+        {
+            strFileExtendName = "bmp";
+        }
+        else if ((photoByte[1] == 80) && (photoByte[2] == 78) && (photoByte[3] == 71))
+        {
+            strFileExtendName = "png";
+        }
+        return strFileExtendName;
+    }
+
+    /**
+     * 获取文件名称 /profile/upload/2022/04/16/ruoyi.png -- ruoyi.png
+     * 
+     * @param fileName 路径名称
+     * @return 没有文件路径的名称
+     */
+    public static String getName(String fileName)
+    {
+        if (fileName == null)
+        {
+            return null;
+        }
+        int lastUnixPos = fileName.lastIndexOf('/');
+        int lastWindowsPos = fileName.lastIndexOf('\\');
+        int index = Math.max(lastUnixPos, lastWindowsPos);
+        return fileName.substring(index + 1);
+    }
+
+    /**
+     * 获取不带后缀文件名称 /profile/upload/2022/04/16/ruoyi.png -- ruoyi
+     * 
+     * @param fileName 路径名称
+     * @return 没有文件路径和后缀的名称
+     */
+    public static String getNameNotSuffix(String fileName)
+    {
+        if (fileName == null)
+        {
+            return null;
+        }
+        String baseName = FilenameUtils.getBaseName(fileName);
+        return baseName;
+    }
+}