优化下载文件

src/main/java/com/ruoyi/common/utils/FileUtils.java

+package com.ruoyi.common.utils;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.OutputStream;
+
+/**
+ * 文件处理工具类
+ * 
+ * @author ruoyi
+ */
+public class FileUtils
+{
+
+    /**
+     * 输出指定文件的byte数组
+     * 
+     * @param filename 文件
+     * @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
+        {
+            if (os != null)
+            {
+                try
+                {
+                    os.close();
+                }
+                catch (IOException e1)
+                {
+                    e1.printStackTrace();
+                }
+            }
+            if (fis != null)
+            {
+                try
+                {
+                    fis.close();
+                }
+                catch (IOException e1)
+                {
+                    e1.printStackTrace();
+                }
+            }
+        }
+    }
+
+    /**
+     * @Desc 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())
+        {
+            file.delete();
+            flag = true;
+        }
+        return flag;
+    }
+
+}