Introduces FileSystemRule

Parent to both DefaultFileSystemRule and EphemeralFileSystemRule.
FileSystemRule also implements FileSystemAbstraction and delegates so there's
no longer need to have fsRule and then get() everywhere. Convenience.

community/io/src/test/java/org/neo4j/test/rule/fs/DefaultFileSystemRule.java

@@ -19,30 +19,12 @@
  */
 package org.neo4j.test.rule.fs;
 
-import org.junit.rules.ExternalResource;
-
 import org.neo4j.io.fs.DefaultFileSystemAbstraction;
-import org.neo4j.io.fs.FileSystemAbstraction;
 
-public class DefaultFileSystemRule extends ExternalResource
+public class DefaultFileSystemRule extends FileSystemRule<DefaultFileSystemAbstraction>
 {
-    private DefaultFileSystemAbstraction fs = new DefaultFileSystemAbstraction();
-
-    @Override
-    protected void after()
-    {
-        try
-        {
-            fs.close();
-        }
-        catch ( Exception e )
-        {
-            throw new RuntimeException( e );
-        }
-    }
-
-    public FileSystemAbstraction get()
+    public DefaultFileSystemRule()
     {
-        return fs;
+        super( new DefaultFileSystemAbstraction() );
     }
 }

community/io/src/test/java/org/neo4j/test/rule/fs/EphemeralFileSystemRule.java

@@ -19,36 +19,17 @@
  */
 package org.neo4j.test.rule.fs;
 
-import org.junit.rules.ExternalResource;
-
 import java.io.File;
 import java.io.IOException;
-import java.util.function.Supplier;
 
 import org.neo4j.graphdb.mockfs.EphemeralFileSystemAbstraction;
 import org.neo4j.io.fs.FileSystemAbstraction;
 
-public class EphemeralFileSystemRule extends ExternalResource implements Supplier<FileSystemAbstraction>
+public class EphemeralFileSystemRule extends FileSystemRule<EphemeralFileSystemAbstraction>
 {
-    private EphemeralFileSystemAbstraction fs = new EphemeralFileSystemAbstraction();
-
-    @Override
-    protected void after()
+    public EphemeralFileSystemRule()
     {
-        try
-        {
-            fs.close();
-        }
-        catch ( Exception e )
-        {
-            throw new RuntimeException( e );
-        }
-    }
-
-    @Override
-    public final EphemeralFileSystemAbstraction get()
-    {
-        return fs;
+        super( new EphemeralFileSystemAbstraction() );
     }
 
     public EphemeralFileSystemAbstraction snapshot( Runnable action ) throws Exception
@@ -72,29 +53,11 @@ public void clear() throws Exception
         fs = new EphemeralFileSystemAbstraction();
     }
 
-    @Override
-    public int hashCode()
-    {
-        return fs.hashCode();
-    }
-
-    @Override
-    public boolean equals( Object obj )
-    {
-        return fs.equals( obj );
-    }
-
     public void crash()
     {
         fs.crash();
     }
 
-    @Override
-    public String toString()
-    {
-        return fs.toString();
-    }
-
     public EphemeralFileSystemAbstraction snapshot()
     {
         return fs.snapshot();

community/io/src/test/java/org/neo4j/test/rule/fs/FileSystemRule.java

@@ -0,0 +1,239 @@
+/*
+ * Copyright (c) 2002-2017 "Neo Technology,"
+ * Network Engine for Objects in Lund AB [http://neotechnology.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.neo4j.test.rule.fs;
+
+import org.junit.rules.ExternalResource;
+
+import java.io.File;
+import java.io.FilenameFilter;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.Reader;
+import java.io.UncheckedIOException;
+import java.io.Writer;
+import java.nio.charset.Charset;
+import java.nio.file.CopyOption;
+import java.util.function.Function;
+import java.util.function.Supplier;
+
+import org.neo4j.io.fs.FileSystemAbstraction;
+import org.neo4j.io.fs.StoreChannel;
+import org.neo4j.io.fs.watcher.FileWatcher;
+
+public abstract class FileSystemRule<FS extends FileSystemAbstraction> extends ExternalResource
+        implements FileSystemAbstraction, Supplier<FileSystemAbstraction>
+{
+    protected volatile FS fs;
+
+    protected FileSystemRule( FS fs )
+    {
+        this.fs = fs;
+    }
+
+    @Override
+    protected void after()
+    {
+        try
+        {
+            fs.close();
+        }
+        catch ( IOException e )
+        {
+            throw new UncheckedIOException( e );
+        }
+        super.after();
+    }
+
+    @Override
+    public FS get()
+    {
+        return fs;
+    }
+
+    @Override
+    public void close() throws IOException
+    {
+        fs.close();
+    }
+
+    @Override
+    public FileWatcher fileWatcher() throws IOException
+    {
+        return fs.fileWatcher();
+    }
+
+    @Override
+    public StoreChannel open( File fileName, String mode ) throws IOException
+    {
+        return fs.open( fileName, mode );
+    }
+
+    @Override
+    public OutputStream openAsOutputStream( File fileName, boolean append ) throws IOException
+    {
+        return fs.openAsOutputStream( fileName, append );
+    }
+
+    @Override
+    public InputStream openAsInputStream( File fileName ) throws IOException
+    {
+        return fs.openAsInputStream( fileName );
+    }
+
+    @Override
+    public Reader openAsReader( File fileName, Charset charset ) throws IOException
+    {
+        return fs.openAsReader( fileName, charset );
+    }
+
+    @Override
+    public Writer openAsWriter( File fileName, Charset charset, boolean append ) throws IOException
+    {
+        return fs.openAsWriter( fileName, charset, append );
+    }
+
+    @Override
+    public StoreChannel create( File fileName ) throws IOException
+    {
+        return fs.create( fileName );
+    }
+
+    @Override
+    public boolean fileExists( File fileName )
+    {
+        return fs.fileExists( fileName );
+    }
+
+    @Override
+    public boolean mkdir( File fileName )
+    {
+        return fs.mkdir( fileName );
+    }
+
+    @Override
+    public void mkdirs( File fileName ) throws IOException
+    {
+        fs.mkdirs( fileName );
+    }
+
+    @Override
+    public long getFileSize( File fileName )
+    {
+        return fs.getFileSize( fileName );
+    }
+
+    @Override
+    public boolean deleteFile( File fileName )
+    {
+        return fs.deleteFile( fileName );
+    }
+
+    @Override
+    public void deleteRecursively( File directory ) throws IOException
+    {
+        fs.deleteRecursively( directory );
+    }
+
+    @Override
+    public void renameFile( File from, File to, CopyOption... copyOptions ) throws IOException
+    {
+        fs.renameFile( from, to, copyOptions );
+    }
+
+    @Override
+    public File[] listFiles( File directory )
+    {
+        return fs.listFiles( directory );
+    }
+
+    @Override
+    public File[] listFiles( File directory, FilenameFilter filter )
+    {
+        return fs.listFiles( directory, filter );
+    }
+
+    @Override
+    public boolean isDirectory( File file )
+    {
+        return fs.isDirectory( file );
+    }
+
+    @Override
+    public void moveToDirectory( File file, File toDirectory ) throws IOException
+    {
+        fs.moveToDirectory( file, toDirectory );
+    }
+
+    @Override
+    public void copyFile( File from, File to ) throws IOException
+    {
+        fs.copyFile( from, to );
+    }
+
+    @Override
+    public void copyRecursively( File fromDirectory, File toDirectory ) throws IOException
+    {
+        fs.copyRecursively( fromDirectory, toDirectory );
+    }
+
+    @Override
+    public <K extends ThirdPartyFileSystem> K getOrCreateThirdPartyFileSystem( Class<K> clazz,
+            Function<Class<K>,K> creator )
+    {
+        return fs.getOrCreateThirdPartyFileSystem( clazz, creator );
+    }
+
+    @Override
+    public void truncate( File path, long size ) throws IOException
+    {
+        fs.truncate( path, size );
+    }
+
+    @Override
+    public long lastModifiedTime( File file ) throws IOException
+    {
+        return fs.lastModifiedTime( file );
+    }
+
+    @Override
+    public void deleteFileOrThrow( File file ) throws IOException
+    {
+        fs.deleteFileOrThrow( file );
+    }
+
+    @Override
+    public int hashCode()
+    {
+        return fs.hashCode();
+    }
+
+    @Override
+    public boolean equals( Object obj )
+    {
+        return fs.equals( obj );
+    }
+
+    @Override
+    public String toString()
+    {
+        return fs.toString();
+    }
+}