feat: add exception handling

data/src/main/java/org/cryptomator/data/cloud/pcloud/PCloudApiError.java

@@ -0,0 +1,90 @@
+package org.cryptomator.data.cloud.pcloud;
+
+public class PCloudApiError {
+
+	public enum PCloudApiErrorCodes {
+		LOGIN_REQUIRED(1000),
+		NO_FULL_PATH_OR_NAME_FOLDER_ID_PROVIDED(1001),
+		NO_FULL_PATH_OR_FOLDER_ID_PROVIDED(1002),
+		NO_FILE_ID_OR_PATH_PROVIDED(1004),
+		INVALID_DATE_TIME_FORMAT(1013),
+		NO_DESTINATION_PROVIDED(1016),
+		INVALID_FOLDER_ID(1017),
+		INVALID_DESTINATION(1037),
+		PROVIDE_URL(1040),
+		UPLOAD_NOT_FOUND(1900),
+		TRANSFER_NOT_FOUND(1902),
+		LOGIN_FAILED(2000),
+		INVALID_FILE_OR_FOLDER_NAME(2001),
+		COMPONENT_OF_PARENT_DIRECTORY_DOES_NOT_EXIST(2002),
+		ACCESS_DENIED(2003),
+		FILE_OR_FOLDER_ALREADY_EXISTS(2004),
+		DIRECTORY_DOES_NOT_EXIST(2005),
+		FOLDER_NOT_EMPTY(2006),
+		CANNOT_DELETE_ROOT_FOLDER(2007),
+		USER_OVER_QUOTA(2008),
+		FILE_NOT_FOUND(2009),
+		INVALID_PATH(2010),
+		SHARED_FOLDER_IN_SHARED_FOLDER(2023),
+		ACTIVE_SHARES_OR_SHAREREQUESTS_PRESENT(2028),
+		CONNECTION_BROKE(2041),
+		CANNOT_RENAME_ROOT_FOLDER(2042),
+		CANNOT_MOVE_FOLDER_INTO_SUBFOLDER_OF_ITSELF(2043),
+		FILE_OR_FOLDER_NOT_FOUND(2055),
+		NO_FILE_UPLOAD_DETECTED(2088),
+		INVALID_ACCESS_TOKEN(2094),
+		ACCESS_TOKEN_REVOKED(2095),
+		TRANSFER_OVER_QUOTA(2097),
+		TARGET_FOLDER_DOES_NOT_EXIST(2208),
+		TOO_MANY_LOGIN_TRIES_FROM_IP(4000),
+		INTERNAL_ERROR(5000),
+		INTERNAL_UPLOAD_ERROR(5001);
+
+		private final int value;
+
+		PCloudApiErrorCodes(final int newValue) {
+			value = newValue;
+		}
+
+		public int getValue() {
+			return value;
+		}
+	}
+
+	public static boolean isCloudNodeAlreadyExistsException(int errorCode) {
+		return errorCode == PCloudApiErrorCodes.FILE_OR_FOLDER_ALREADY_EXISTS.getValue();
+	}
+
+	public static boolean isFatalBackendException(int errorCode) {
+		return errorCode == PCloudApiErrorCodes.INTERNAL_UPLOAD_ERROR.getValue()
+				|| errorCode == PCloudApiErrorCodes.INTERNAL_UPLOAD_ERROR.getValue()
+				|| errorCode == PCloudApiErrorCodes.UPLOAD_NOT_FOUND.getValue()
+				|| errorCode == PCloudApiErrorCodes.TRANSFER_NOT_FOUND.getValue();
+	}
+
+	public static boolean isForbiddenException(int errorCode) {
+		return errorCode == PCloudApiErrorCodes.ACCESS_DENIED.getValue();
+	}
+
+	public static boolean isNetworkConnectionException(int errorCode) {
+		return errorCode == PCloudApiErrorCodes.CONNECTION_BROKE.getValue();
+	}
+
+	public static boolean isNoSuchCloudFileException(int errorCode) {
+		return errorCode == PCloudApiErrorCodes.FILE_NOT_FOUND.getValue()
+				|| errorCode == PCloudApiErrorCodes.FILE_OR_FOLDER_NOT_FOUND.getValue()
+				|| errorCode == PCloudApiErrorCodes.DIRECTORY_DOES_NOT_EXIST.getValue();
+	}
+
+	public static boolean isWrongCredentialsException(int errorCode) {
+		return errorCode == PCloudApiErrorCodes.INVALID_ACCESS_TOKEN.getValue()
+				|| errorCode == PCloudApiErrorCodes.ACCESS_TOKEN_REVOKED.getValue();
+	}
+
+	public static boolean isUnauthorizedException(int errorCode) {
+		return errorCode == PCloudApiErrorCodes.LOGIN_FAILED.getValue()
+				|| errorCode == PCloudApiErrorCodes.LOGIN_REQUIRED.getValue()
+				|| errorCode == PCloudApiErrorCodes.TOO_MANY_LOGIN_TRIES_FROM_IP.getValue();
+	}
+
+}

data/src/main/java/org/cryptomator/data/cloud/pcloud/PCloudApiErrorCodes.java

@@ -1,39 +0,0 @@
-package org.cryptomator.data.cloud.pcloud;
-
-public enum PCloudApiErrorCodes {
-	LOGIN_REQUIRED(1000),
-	NO_FULL_PATH_OR_NAME_FOLDER_ID_PROVIDED(1001),
-	NO_FULL_PATH_OR_FOLDER_ID_PROVIDED(1002),
-	NO_DESTINATION_PROVIDED(1016),
-	INVALID_FOLDER_ID(1017),
-	INVALID_DESTINATION(1037),
-	PROVIDE_URL(1040),
-	LOGIN_FAILED(2000),
-	INVALID_FILE_OR_FOLDER_NAME(2001),
-	COMPONENT_OF_PARENT_DIRECTORY_DOES_NOT_EXIST(2002),
-	ACCESS_DENIED(2003),
-	FILE_OR_FOLDER_ALREADY_EXISTS(2004),
-	DIRECTORY_DOES_NOT_EXIST(2005),
-	FOLDER_NOT_EMPTY(2006),
-	CANNOT_DELETE_ROOT_FOLDER(2007),
-	USER_OVER_QUOTA(2008),
-	FILE_NOT_FOUND(2009),
-	SHARED_FOLDER_IN_SHARED_FOLDER(2023),
-	ACTIVE_SHARES_OR_SHAREREQUESTS_PRESENT(2028),
-	CANNOT_RENAME_ROOT_FOLDER(2042),
-	CANNOT_MOVE_FOLDER_INTO_SUBFOLDER_OF_ITSELF(2043),
-	FILE_OR_FOLDER_NOT_FOUND(2055),
-	INVALID_ACCESS_TOKEN(2094),
-	ACCESS_TOKEN_REVOKED(2095),
-	TOO_MANY_LOGIN_TRIES_FROM_IP(4000),
-	INTERNAL_ERROR(5000),
-	INTERNAL_UPLOAD_ERROR(5001);
-
-	private final int value;
-
-	PCloudApiErrorCodes(final int newValue) {
-		value = newValue;
-	}
-
-	public int getValue() { return value; }
-}

data/src/main/java/org/cryptomator/data/cloud/pcloud/PCloudContentRepository.java

@@ -50,7 +50,8 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 	private void throwWrongCredentialsExceptionIfRequired(Exception e) {
 		if (e instanceof ApiError) {
 			int errorCode = ((ApiError)e).errorCode();
-			if (errorCode == PCloudApiErrorCodes.INVALID_ACCESS_TOKEN.getValue() || errorCode == PCloudApiErrorCodes.ACCESS_TOKEN_REVOKED.getValue()) {
+			if (errorCode == PCloudApiError.PCloudApiErrorCodes.INVALID_ACCESS_TOKEN.getValue()
+					|| errorCode == PCloudApiError.PCloudApiErrorCodes.ACCESS_TOKEN_REVOKED.getValue()) {
 				throw new WrongCredentialsException(cloud);
 			}
 		}
@@ -69,30 +70,46 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 		}
 
 		@Override
-		public PCloudFolder resolve(PCloud cloud, String path) {
+		public PCloudFolder resolve(PCloud cloud, String path) throws BackendException {
+			try {
 				return this.cloud.resolve(path);
+			} catch(IOException ex) {
+				throw new FatalBackendException(ex);
+			}
 		}
 
 		@Override
-		public PCloudFile file(PCloudFolder parent, String name) {
+		public PCloudFile file(PCloudFolder parent, String name) throws BackendException {
+			try {
 				return cloud.file(parent, name);
+			} catch(IOException ex) {
+				throw new FatalBackendException(ex);
+			}
 		}
 
 		@Override
 		public PCloudFile file(PCloudFolder parent, String name, Optional<Long> size) throws BackendException {
+			try {
 				return cloud.file(parent, name, size);
+			} catch(IOException ex) {
+				throw new FatalBackendException(ex);
+			}
 		}
 
 		@Override
-		public PCloudFolder folder(PCloudFolder parent, String name) {
+		public PCloudFolder folder(PCloudFolder parent, String name) throws BackendException {
+			try {
 				return cloud.folder(parent, name);
+			} catch(IOException ex) {
+				throw new FatalBackendException(ex);
+			}
 		}
 
 		@Override
 		public boolean exists(PCloudNode node) throws BackendException {
 			try {
 				return cloud.exists(node);
-			} catch (ApiError|IOException e) {
+			} catch (IOException e) {
 				throw new FatalBackendException(e);
 			}
 		}
@@ -101,12 +118,7 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 		public List<PCloudNode> list(PCloudFolder folder) throws BackendException {
 			try {
 				return cloud.list(folder);
-			} catch (ApiError | IOException e) {
+			} catch (IOException e) {
-				if (e instanceof ApiError) {
-					if (((ApiError) e).errorCode() == PCloudApiErrorCodes.DIRECTORY_DOES_NOT_EXIST.getValue()) {
-						throw new NoSuchCloudFileException();
-					}
-				}
 				throw new FatalBackendException(e);
 			}
 		}
@@ -115,11 +127,7 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 		public PCloudFolder create(PCloudFolder folder) throws BackendException {
 			try {
 				return cloud.create(folder);
-			} catch (ApiError | IOException e) {
+			} catch (IOException e) {
-				if (e instanceof ApiError) {
-					if (((ApiError) e).errorCode() == PCloudApiErrorCodes.FILE_OR_FOLDER_ALREADY_EXISTS.getValue())
-					throw new CloudNodeAlreadyExistsException(folder.getName());
-				}
 				throw new FatalBackendException(e);
 			}
 		}
@@ -128,15 +136,7 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 		public PCloudFolder move(PCloudFolder source, PCloudFolder target) throws BackendException {
 			try {
 				return (PCloudFolder) cloud.move(source, target);
-			} catch (ApiError | IOException e) {
+			} catch (IOException e) {
-				if (e instanceof ApiError) {
-					if (((ApiError)e).errorCode() == PCloudApiErrorCodes.DIRECTORY_DOES_NOT_EXIST.getValue()) {
-						throw new NoSuchCloudFileException(source.getName());
-					} else if (((ApiError)e).errorCode() == PCloudApiErrorCodes.FILE_OR_FOLDER_ALREADY_EXISTS.getValue()) {
-						throw new CloudNodeAlreadyExistsException(target.getName());
-					}
-					throw new CloudNodeAlreadyExistsException(target.getName());
-				}
 				throw new FatalBackendException(e);
 			}
 		}
@@ -145,15 +145,7 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 		public PCloudFile move(PCloudFile source, PCloudFile target) throws BackendException {
 			try {
 				return (PCloudFile) cloud.move(source, target);
-			} catch (ApiError | IOException e) {
+			} catch (IOException e) {
-				if (e instanceof ApiError) {
-					if (((ApiError)e).errorCode() == PCloudApiErrorCodes.FILE_NOT_FOUND.getValue()) {
-						throw new NoSuchCloudFileException(source.getName());
-					} else if (((ApiError)e).errorCode() == PCloudApiErrorCodes.FILE_OR_FOLDER_ALREADY_EXISTS.getValue()) {
-						throw new CloudNodeAlreadyExistsException(target.getName());
-					}
-					throw new CloudNodeAlreadyExistsException(target.getName());
-				}
 				throw new FatalBackendException(e);
 			}
 		}
@@ -162,10 +154,7 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 		public PCloudFile write(PCloudFile uploadFile, DataSource data, ProgressAware<UploadState> progressAware, boolean replace, long size) throws BackendException {
 			try {
 				return cloud.write(uploadFile, data, progressAware, replace, size);
-			} catch (ApiError | IOException e) {
+			} catch (IOException e) {
-				if (e instanceof ApiError && ((ApiError)e).errorCode() == PCloudApiErrorCodes.FILE_NOT_FOUND.getValue()) {
-					throw new NoSuchCloudFileException(uploadFile.getName());
-				}
 				throw new FatalBackendException(e);
 			}
 		}
@@ -174,10 +163,7 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 		public void read(PCloudFile file, Optional<File> encryptedTmpFile, OutputStream data, ProgressAware<DownloadState> progressAware) throws BackendException {
 			try {
 				cloud.read(file, data, progressAware);
-			} catch (ApiError | IOException e) {
+			} catch (IOException e) {
-				if (e instanceof ApiError && ((ApiError)e).errorCode() == PCloudApiErrorCodes.FILE_NOT_FOUND.getValue()) {
-					throw new NoSuchCloudFileException(file.getName());
-				}
 				throw new FatalBackendException(e);
 			}
 		}
@@ -186,12 +172,7 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 		public void delete(PCloudNode node) throws BackendException {
 			try {
 				cloud.delete(node);
-			} catch (ApiError | IOException e) {
+			} catch (IOException e) {
-				if (e instanceof ApiError) {
-					if (((ApiError) e).errorCode() == PCloudApiErrorCodes.FILE_NOT_FOUND.getValue()) {
-						throw new NoSuchCloudFileException(node.getName());
-					}
-				}
 				throw new FatalBackendException(e);
 			}
 		}
@@ -200,7 +181,7 @@ class PCloudContentRepository extends InterceptingCloudContentRepository<PCloud,
 		public String checkAuthenticationAndRetrieveCurrentAccount(PCloud cloud) throws BackendException {
 			try {
 				return this.cloud.currentAccount();
-			} catch (ApiError | IOException e) {
+			} catch (IOException e) {
 				throw new FatalBackendException(e);
 			}
 		}

data/src/main/java/org/cryptomator/data/cloud/pcloud/PCloudImpl.java

@@ -18,7 +18,11 @@ import org.cryptomator.data.util.CopyStream;
 import org.cryptomator.domain.PCloud;
 import org.cryptomator.domain.exception.BackendException;
 import org.cryptomator.domain.exception.CloudNodeAlreadyExistsException;
+import org.cryptomator.domain.exception.FatalBackendException;
+import org.cryptomator.domain.exception.ForbiddenException;
+import org.cryptomator.domain.exception.NetworkConnectionException;
 import org.cryptomator.domain.exception.NoSuchCloudFileException;
+import org.cryptomator.domain.exception.UnauthorizedException;
 import org.cryptomator.domain.exception.authentication.NoAuthenticationProvidedException;
 import org.cryptomator.domain.exception.authentication.WrongCredentialsException;
 import org.cryptomator.domain.usecases.ProgressAware;
@@ -33,8 +37,11 @@ import java.io.OutputStream;
 import java.net.URLEncoder;
 import java.util.ArrayList;
 import java.util.Date;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
+import okhttp3.internal.concurrent.TaskRunner;
 import okio.BufferedSink;
 import okio.BufferedSource;
 import okio.Okio;
@@ -51,6 +58,8 @@ class PCloudImpl {
 	private final RootPCloudFolder root;
 	private final Context context;
 
+	private final String UTF_8 = "UTF-8";
+
 	PCloudImpl(Context context, PCloud cloud, PCloudIdCache idCache) {
 		if (cloud.accessToken() == null) {
 			throw new NoAuthenticationProvidedException(cloud);
@@ -70,7 +79,7 @@ class PCloudImpl {
 		return root;
 	}
 
-	public PCloudFolder resolve(String path) {
+	public PCloudFolder resolve(String path) throws IOException, BackendException {
 		if (path.startsWith("/")) {
 			path = path.substring(1);
 		}
@@ -82,7 +91,7 @@ class PCloudImpl {
 		return folder;
 	}
 
-	private Optional<RemoteEntry> findEntry(Long folderId, String name, boolean isFolder) {
+	private Optional<RemoteEntry> findEntry(Long folderId, String name, boolean isFolder) throws IOException, BackendException {
 		try {
 			RemoteFolder remoteFolder = client().listFolder(folderId).execute();
 			for (RemoteEntry remoteEntry : remoteFolder.children()) {
@@ -97,22 +106,19 @@ class PCloudImpl {
 				}
 			}
 			return Optional.empty();
-		} catch(ApiError | IOException ex) {
+		} catch(ApiError ex) {
-			if (ex instanceof ApiError) {
+			Set<Integer> ignoredErrorCodes = new HashSet<>();
-				int errorCode = ((ApiError)ex).errorCode();
+			ignoredErrorCodes.add(PCloudApiError.PCloudApiErrorCodes.DIRECTORY_DOES_NOT_EXIST.getValue());
-				if (errorCode == PCloudApiErrorCodes.INVALID_ACCESS_TOKEN.getValue() || errorCode == PCloudApiErrorCodes.ACCESS_TOKEN_REVOKED.getValue()) {
+			handleApiError(ex, ignoredErrorCodes);
-					throw new WrongCredentialsException(cloud);
-				}
-			}
 			return Optional.empty();
 		}
 	}
 
-	public PCloudFile file(PCloudFolder parent, String name) {
+	public PCloudFile file(PCloudFolder parent, String name) throws BackendException, IOException {
 		return file(parent, name, Optional.empty());
 	}
 
-	public PCloudFile file(PCloudFolder parent, String name, Optional<Long> size) {
+	public PCloudFile file(PCloudFolder parent, String name, Optional<Long> size) throws BackendException, IOException {
 		if (parent.getId() == null) {
 			return PCloudNodeFactory.file(parent, name, size);
 		}
@@ -131,7 +137,7 @@ class PCloudImpl {
 		return PCloudNodeFactory.file(parent, name, size);
 	}
 
-	public PCloudFolder folder(PCloudFolder parent, String name) {
+	public PCloudFolder folder(PCloudFolder parent, String name) throws IOException, BackendException {
 		if (parent.getId() == null) {
 			return PCloudNodeFactory.folder(parent, name);
 		}
@@ -149,7 +155,7 @@ class PCloudImpl {
 		return PCloudNodeFactory.folder(parent, name);
 	}
 
-	public boolean exists(PCloudNode node) throws ApiError, IOException {
+	public boolean exists(PCloudNode node) throws IOException, BackendException {
 		try {
 			if (node instanceof PCloudFolder) {
 				RemoteFolder remoteFolder = client().listFolder(node.getPath()).execute();
@@ -159,22 +165,23 @@ class PCloudImpl {
 				idCache.add(PCloudNodeFactory.file(node.getParent(), remoteFile));
 			}
 			return true;
-		} catch (ApiError e) {
+		} catch (ApiError ex) {
-			if (e.errorCode() == PCloudApiErrorCodes.DIRECTORY_DOES_NOT_EXIST.getValue()
+			Set<Integer> ignoredErrorCodes = new HashSet<>();
-					|| e.errorCode() == PCloudApiErrorCodes.COMPONENT_OF_PARENT_DIRECTORY_DOES_NOT_EXIST.getValue()
+			ignoredErrorCodes.add(PCloudApiError.PCloudApiErrorCodes.DIRECTORY_DOES_NOT_EXIST.getValue());
-					|| e.errorCode() == PCloudApiErrorCodes.INVALID_FILE_OR_FOLDER_NAME.getValue()
+			ignoredErrorCodes.add(PCloudApiError.PCloudApiErrorCodes.COMPONENT_OF_PARENT_DIRECTORY_DOES_NOT_EXIST.getValue());
-					|| e.errorCode() == PCloudApiErrorCodes.FILE_OR_FOLDER_NOT_FOUND.getValue()) {
+			ignoredErrorCodes.add(PCloudApiError.PCloudApiErrorCodes.INVALID_FILE_OR_FOLDER_NAME.getValue());
+			ignoredErrorCodes.add(PCloudApiError.PCloudApiErrorCodes.FILE_OR_FOLDER_NOT_FOUND.getValue());
+			handleApiError(ex, ignoredErrorCodes);
 			return false;
 		}
-			throw e;
-		}
 	}
 
-	public List<PCloudNode> list(PCloudFolder folder) throws ApiError, IOException {
+	public List<PCloudNode> list(PCloudFolder folder) throws IOException, BackendException {
 		List<PCloudNode> result = new ArrayList<>();
 
 		Long folderId = folder.getId();
 		RemoteFolder listFolderResult;
+		try {
 			if (folderId == null) {
 				listFolderResult = client().listFolder(folder.getPath()).execute();
 			} else {
@@ -182,15 +189,18 @@ class PCloudImpl {
 						.listFolder(folder.getId()) //
 						.execute();
 			}
-
 			List<RemoteEntry> entryMetadata = listFolderResult.children();
 			for (RemoteEntry metadata : entryMetadata) {
 				result.add(idCache.cache(PCloudNodeFactory.from(folder, metadata)));
 			}
 			return result;
+		} catch(ApiError ex) {
+			handleApiError(ex);
+			throw new FatalBackendException(ex);
+		}
 	}
 
-	public PCloudFolder create(PCloudFolder folder) throws ApiError, IOException  {
+	public PCloudFolder create(PCloudFolder folder) throws IOException, BackendException  {
 		if (folder.getParent().getId() == null) {
 			folder = new PCloudFolder( //
 					create(folder.getParent()), //
@@ -199,20 +209,26 @@ class PCloudImpl {
 			);
 		}
 
+		try {
 			RemoteFolder createdFolder = client() //
 					.createFolder(folder.getParent().getId(), folder.getName()) //
 					.execute();
 			return idCache.cache( //
 					PCloudNodeFactory.folder(folder.getParent(), createdFolder));
+		} catch (ApiError ex) {
+			handleApiError(ex);
+			throw new FatalBackendException(ex);
+		}
 	}
 
-	public PCloudNode move(PCloudNode source, PCloudNode target) throws ApiError, BackendException, IOException {
+	public PCloudNode move(PCloudNode source, PCloudNode target) throws IOException, BackendException {
 		if (exists(target)) {
 			throw new CloudNodeAlreadyExistsException(target.getName());
 		}
 
 		RemoteEntry relocationResult;
 
+		try {
 			if (source instanceof PCloudFolder) {
 				relocationResult = client().moveFolder(source.getId(), target.getParent().getId()).execute();
 				if (!relocationResult.name().equals(target.getName())) {
@@ -227,10 +243,14 @@ class PCloudImpl {
 
 			idCache.remove(source);
 			return idCache.cache(PCloudNodeFactory.from(target.getParent(), relocationResult));
+		} catch(ApiError ex) {
+			handleApiError(ex);
+			throw new FatalBackendException(ex);
+		}
 	}
 
 	public PCloudFile write(PCloudFile file, DataSource data, final ProgressAware<UploadState> progressAware, boolean replace, long size)
-			throws ApiError, BackendException, IOException {
+			throws IOException, BackendException {
 		if (!replace && exists(file)) {
 			throw new CloudNodeAlreadyExistsException("CloudNode already exists and replace is false");
 		}
@@ -253,7 +273,7 @@ class PCloudImpl {
 	}
 
 	private RemoteFile uploadFile(final PCloudFile file, DataSource data, final ProgressAware<UploadState> progressAware, UploadOptions uploadOptions, final long size) //
-			throws ApiError, IOException {
+			throws IOException, BackendException {
 			ProgressListener listener = (done, total) -> progressAware.onProgress( //
 					progress(UploadState.upload(file)) //
 							.between(0) //
@@ -280,19 +300,23 @@ class PCloudImpl {
 		}
 
 		String filename = file.getName();
-		String encodedFilename = URLEncoder.encode(filename, "UTF-8");
+		String encodedFilename = URLEncoder.encode(filename, UTF_8);
 
+		try {
 			RemoteFile newFile = client() //
 					.createFile(parentFolderId, encodedFilename, pCloudDataSource, new Date(), listener, uploadOptions) //
 					.execute();
 			if (!filename.equals(encodedFilename)) {
 				return client().renameFile(newFile.fileId(), filename).execute();
 			}
-
 			return newFile;
+		} catch (ApiError ex) {
+			handleApiError(ex);
+			throw new FatalBackendException(ex);
+		}
 	}
 
-	public void read(PCloudFile file, OutputStream data, final ProgressAware<DownloadState> progressAware) throws ApiError, IOException {
+	public void read(PCloudFile file, OutputStream data, final ProgressAware<DownloadState> progressAware) throws IOException, BackendException {
 		progressAware.onProgress(Progress.started(DownloadState.download(file)));
 
 		Long fileId = file.getId();
@@ -300,6 +324,7 @@ class PCloudImpl {
 			fileId = idCache.get(file.getPath()).getId();
 		}
 
+		try {
 			FileLink fileLink = client().createFileLink(fileId, DownloadOptions.DEFAULT).execute();
 
 			ProgressListener listener = (done, total) -> progressAware.onProgress( //
@@ -318,9 +343,13 @@ class PCloudImpl {
 			client().download(fileLink, sink, listener).execute();
 
 			progressAware.onProgress(Progress.completed(DownloadState.download(file)));
+		} catch(ApiError ex) {
+			handleApiError(ex);
+		}
 	}
 
-	public void delete(PCloudNode node) throws ApiError, IOException {
+	public void delete(PCloudNode node) throws IOException, BackendException {
+		try {
 			if (node instanceof PCloudFolder) {
 				client() //
 						.deleteFolder(node.getId(), true).execute();
@@ -329,12 +358,49 @@ class PCloudImpl {
 						.deleteFile(node.getId()).execute();
 			}
 			idCache.remove(node);
+		} catch(ApiError ex) {
+			handleApiError(ex);
+		}
 	}
 
-	public String currentAccount() throws ApiError, IOException {
+	public String currentAccount() throws IOException, BackendException {
+		try {
 			UserInfo currentAccount = client() //
 					.getUserInfo() //
 					.execute();
 			return currentAccount.email();
+		} catch(ApiError ex) {
+			handleApiError(ex);
+			throw new FatalBackendException(ex);
+		}
+	}
+
+	private void handleApiError(ApiError ex) throws BackendException {
+		handleApiError(ex, null);
+	}
+
+	private void handleApiError(ApiError ex, Set<Integer> errorCodes) throws BackendException {
+		handleApiError(ex, errorCodes, null);
+	}
+
+	private void handleApiError(ApiError ex, Set<Integer> errorCodes, String name) throws BackendException {
+		if (errorCodes == null  || !errorCodes.contains(ex.errorCode())) {
+			int errorCode = ex.errorCode();
+			if (PCloudApiError.isCloudNodeAlreadyExistsException(errorCode)) {
+				throw new CloudNodeAlreadyExistsException(name);
+			} else if (PCloudApiError.isForbiddenException(errorCode)){
+				throw new ForbiddenException();
+			} else if (PCloudApiError.isNetworkConnectionException(errorCode)) {
+				throw new NetworkConnectionException(ex);
+			} else if (PCloudApiError.isNoSuchCloudFileException(errorCode)) {
+				throw new NoSuchCloudFileException(name);
+			} else if (PCloudApiError.isWrongCredentialsException(errorCode)) {
+				throw new WrongCredentialsException(cloud);
+			} else if (PCloudApiError.isUnauthorizedException(errorCode)) {
+				throw new UnauthorizedException();
+			} else {
+				throw new FatalBackendException(ex);
+			}
+		}
 	}
 }