support for RFC 4331: DAV:quota-available-bytes and DAV:quota-used-bytes

references #97; quota calculation in NIO filesystem still missing

main/filesystem-api/src/main/java/org/cryptomator/filesystem/FileSystem.java

@@ -23,4 +23,8 @@ public interface FileSystem extends Folder {
 		return Optional.empty();
 	}
 
+	Optional<Long> quotaUsedBytes();
+
+	Optional<Long> quotaAvailableBytes();
+
 }

main/filesystem-api/src/main/java/org/cryptomator/filesystem/delegating/DelegatingFileSystem.java

@@ -0,0 +1,22 @@
+package org.cryptomator.filesystem.delegating;
+
+import java.util.Optional;
+
+import org.cryptomator.filesystem.FileSystem;
+import org.cryptomator.filesystem.Folder;
+
+public interface DelegatingFileSystem extends FileSystem {
+
+	Folder getDelegate();
+
+	@Override
+	default Optional<Long> quotaUsedBytes() {
+		return getDelegate().fileSystem().quotaUsedBytes();
+	}
+
+	@Override
+	default Optional<Long> quotaAvailableBytes() {
+		return getDelegate().fileSystem().quotaAvailableBytes();
+	}
+
+}

main/filesystem-api/src/test/java/org/cryptomator/filesystem/delegating/DelegatingFileSystemTest.java

@@ -0,0 +1,32 @@
+package org.cryptomator.filesystem.delegating;
+
+import java.util.Optional;
+
+import org.cryptomator.filesystem.FileSystem;
+import org.junit.Assert;
+import org.junit.Test;
+import org.mockito.Mockito;
+
+public class DelegatingFileSystemTest {
+
+	@Test
+	public void testQuotaAvailableBytes() {
+		FileSystem mockFs = Mockito.mock(FileSystem.class);
+		Mockito.when(mockFs.fileSystem()).thenReturn(mockFs);
+		Mockito.when(mockFs.quotaAvailableBytes()).thenReturn(Optional.of(42l));
+
+		DelegatingFileSystem delegatingFs = TestDelegatingFileSystem.withRoot(mockFs);
+		Assert.assertEquals(mockFs.quotaAvailableBytes(), delegatingFs.quotaAvailableBytes());
+	}
+
+	@Test
+	public void testQuotaUsedBytes() {
+		FileSystem mockFs = Mockito.mock(FileSystem.class);
+		Mockito.when(mockFs.fileSystem()).thenReturn(mockFs);
+		Mockito.when(mockFs.quotaUsedBytes()).thenReturn(Optional.of(23l));
+
+		DelegatingFileSystem delegatingFs = TestDelegatingFileSystem.withRoot(mockFs);
+		Assert.assertEquals(mockFs.quotaUsedBytes(), delegatingFs.quotaUsedBytes());
+	}
+
+}

main/filesystem-api/src/test/java/org/cryptomator/filesystem/delegating/TestDelegatingFileSystem.java

@@ -1,9 +1,8 @@
 package org.cryptomator.filesystem.delegating;
 
-import org.cryptomator.filesystem.FileSystem;
 import org.cryptomator.filesystem.Folder;
 
-class TestDelegatingFileSystem extends TestDelegatingFolder implements FileSystem {
+class TestDelegatingFileSystem extends TestDelegatingFolder implements DelegatingFileSystem {
 
 	private TestDelegatingFileSystem(Folder delegate) {
 		super(null, delegate);
@@ -13,4 +12,9 @@ class TestDelegatingFileSystem extends TestDelegatingFolder implements FileSyste
 		return new TestDelegatingFileSystem(delegate);
 	}
 
+	@Override
+	public Folder getDelegate() {
+		return delegate;
+	}
+
 }