Optimize FileHandler's logic (#639)

* optimize FileHandler's logic

* fix code style

* fix: maybe happen OOM when file upload, see #529

* refactor: HashMap -> ConcurrentHashMap

* remove unused class

src/main/java/run/halo/app/exception/RepeatTypeException.java

@@ -0,0 +1,15 @@
+package run.halo.app.exception;
+
+/**
+ * repeat type exception
+ * @author bestsort
+ * @date 3/13/20 5:03 PM
+ */
+public class RepeatTypeException extends ServiceException {
+    public RepeatTypeException(String message) {
+        super(message);
+    }
+    public RepeatTypeException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/run/halo/app/handler/file/AliOssFileHandler.java

@@ -148,7 +148,8 @@ public class AliOssFileHandler implements FileHandler {
     }
 
     @Override
-    public boolean supportType(String type) {
-        return AttachmentType.ALIOSS.name().equalsIgnoreCase(type);
+    public AttachmentType getAttachmentType() {
+        return AttachmentType.ALIOSS;
     }
+
 }

src/main/java/run/halo/app/handler/file/BaiduBosFileHandler.java

@@ -132,7 +132,7 @@ public class BaiduBosFileHandler implements FileHandler {
     }
 
     @Override
-    public boolean supportType(String type) {
-        return AttachmentType.BAIDUBOS.name().equalsIgnoreCase(type);
+    public AttachmentType getAttachmentType() {
+        return AttachmentType.BAIDUBOS;
     }
 }

src/main/java/run/halo/app/handler/file/FileHandler.java

@@ -7,6 +7,7 @@ import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.web.multipart.MultipartFile;
 import run.halo.app.exception.FileOperationException;
+import run.halo.app.model.enums.AttachmentType;
 import run.halo.app.model.support.UploadResult;
 
 import static run.halo.app.model.support.HaloConst.FILE_SEPARATOR;
@@ -73,10 +74,8 @@ public interface FileHandler {
     void delete(@NonNull String key);
 
     /**
-     * Checks if the given type is supported.
-     *
-     * @param type attachment type
-     * @return true if supported; false otherwise
+     * Get attachment type is supported.
+     * @return attachment type
      */
-    boolean supportType(@Nullable String type);
-}
+    AttachmentType getAttachmentType();
+}

src/main/java/run/halo/app/handler/file/FileHandlers.java

@@ -9,12 +9,13 @@ import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
 import org.springframework.web.multipart.MultipartFile;
 import run.halo.app.exception.FileOperationException;
+import run.halo.app.exception.RepeatTypeException;
 import run.halo.app.model.entity.Attachment;
 import run.halo.app.model.enums.AttachmentType;
 import run.halo.app.model.support.UploadResult;
 
 import java.util.Collection;
-import java.util.LinkedList;
+import java.util.concurrent.ConcurrentHashMap;
 
 /**
  * File handler manager.
@@ -29,7 +30,7 @@ public class FileHandlers {
     /**
      * File handler container.
      */
-    private final Collection<FileHandler> fileHandlers = new LinkedList<>();
+    private final ConcurrentHashMap<AttachmentType, FileHandler> fileHandlers = new ConcurrentHashMap<>(16);
 
     public FileHandlers(ApplicationContext applicationContext) {
         // Add all file handler
@@ -47,31 +48,9 @@ public class FileHandlers {
      */
     @NonNull
     public UploadResult upload(@NonNull MultipartFile file, @NonNull AttachmentType attachmentType) {
-        Assert.notNull(attachmentType, "Attachment type must not be null");
-
-        return upload(file, attachmentType.name());
+        return getSupportedType(attachmentType).upload(file);
     }
 
-    /**
-     * Uploads files.
-     *
-     * @param file multipart file must not be null
-     * @param type store type
-     * @return upload result
-     * @throws FileOperationException throws when fail to delete attachment or no available file handler to upload it
-     */
-    @NonNull
-    public UploadResult upload(@NonNull MultipartFile file, @Nullable String type) {
-        Assert.notNull(file, "Multipart file must not be null");
-
-        for (FileHandler fileHandler : fileHandlers) {
-            if (fileHandler.supportType(type)) {
-                return fileHandler.upload(file);
-            }
-        }
-
-        throw new FileOperationException("No available file handlers to upload the file").setErrorData(type);
-    }
 
     /**
      * Deletes attachment.
@@ -81,26 +60,8 @@ public class FileHandlers {
      */
     public void delete(@NonNull Attachment attachment) {
         Assert.notNull(attachment, "Attachment must not be null");
-
-        delete(attachment.getType().name(), attachment.getFileKey());
-    }
-
-    /**
-     * Deletes attachment.
-     *
-     * @param key file key
-     * @throws FileOperationException throws when fail to delete attachment or no available file handler to delete it
-     */
-    public void delete(@Nullable String type, @NonNull String key) {
-        for (FileHandler fileHandler : fileHandlers) {
-            if (fileHandler.supportType(type)) {
-                // Delete the file
-                fileHandler.delete(key);
-                return;
-            }
-        }
-
-        throw new FileOperationException("No available file handlers to delete the file").setErrorData(type);
+        getSupportedType(attachment.getType())
+                .delete(attachment.getFileKey());
     }
 
     /**
@@ -112,8 +73,21 @@ public class FileHandlers {
     @NonNull
     public FileHandlers addFileHandlers(@Nullable Collection<FileHandler> fileHandlers) {
         if (!CollectionUtils.isEmpty(fileHandlers)) {
-            this.fileHandlers.addAll(fileHandlers);
+            for (FileHandler handler : fileHandlers) {
+                if (this.fileHandlers.containsKey(handler.getAttachmentType())) {
+                    throw new RepeatTypeException("Same attachment type implements must be unique");
+                }
+                this.fileHandlers.put(handler.getAttachmentType(), handler);
+            }
         }
         return this;
     }
+
+    private FileHandler getSupportedType(AttachmentType type) {
+        FileHandler handler = fileHandlers.getOrDefault(type, fileHandlers.get(AttachmentType.LOCAL));
+        if (handler == null) {
+            throw new FileOperationException("No available file handlers to operate the file").setErrorData(type);
+        }
+        return handler;
+    }
 }

src/main/java/run/halo/app/handler/file/LocalFileHandler.java

@@ -214,8 +214,8 @@ public class LocalFileHandler implements FileHandler {
     }
 
     @Override
-    public boolean supportType(String type) {
-        return AttachmentType.LOCAL.name().equalsIgnoreCase(type);
+    public AttachmentType getAttachmentType() {
+        return AttachmentType.LOCAL;
     }
 
     private boolean generateThumbnail(BufferedImage originalImage, Path thumbPath, String extension) {
@@ -234,6 +234,9 @@ public class LocalFileHandler implements FileHandler {
             result = true;
         } catch (Throwable t) {
             log.warn("Failed to generate thumbnail: " + thumbPath, t);
+        } finally {
+            // Disposes of this graphics context and releases any system resources that it is using.
+            originalImage.getGraphics().dispose();
         }
         return result;
     }

src/main/java/run/halo/app/handler/file/QiniuOssFileHandler.java

@@ -177,7 +177,7 @@ public class QiniuOssFileHandler implements FileHandler {
     }
 
     @Override
-    public boolean supportType(String type) {
-        return AttachmentType.QINIUOSS.name().equalsIgnoreCase(type);
+    public AttachmentType getAttachmentType() {
+        return AttachmentType.QINIUOSS;
     }
 }

src/main/java/run/halo/app/handler/file/SmmsFileHandler.java

@@ -165,8 +165,8 @@ public class SmmsFileHandler implements FileHandler {
     }
 
     @Override
-    public boolean supportType(String type) {
-        return AttachmentType.SMMS.name().equalsIgnoreCase(type);
+    public AttachmentType getAttachmentType() {
+        return AttachmentType.SMMS;
     }
 
     /**

src/main/java/run/halo/app/handler/file/TencentCosFileHandler.java

@@ -163,7 +163,7 @@ public class TencentCosFileHandler implements FileHandler {
     }
 
     @Override
-    public boolean supportType(String type) {
-        return AttachmentType.TENCENTCOS.name().equalsIgnoreCase(type);
+    public AttachmentType getAttachmentType() {
+        return AttachmentType.TENCENTCOS;
     }
 }

src/main/java/run/halo/app/handler/file/UpOssFileHandler.java

@@ -128,7 +128,7 @@ public class UpOssFileHandler implements FileHandler {
     }
 
     @Override
-    public boolean supportType(String type) {
-        return AttachmentType.UPOSS.name().equalsIgnoreCase(type);
+    public AttachmentType getAttachmentType() {
+        return AttachmentType.UPOSS;
     }
 }

src/main/java/run/halo/app/service/impl/ThemeServiceImpl.java

@@ -934,7 +934,6 @@ public class ThemeServiceImpl implements ThemeService {
                 return true;
             }
         }
-
         return false;
     }
 }