1 files changed, 92 insertions, 0 deletions
diff --git a/src/main/java/de/waldheinz/fs/AbstractFileSystem.java b/src/main/java/de/waldheinz/fs/AbstractFileSystem.java
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+++ b/src/main/java/de/waldheinz/fs/AbstractFileSystem.java
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+/*
+ * Copyright (C) 2003-2009 JNode.org
+ *               2009,2010 Matthias Treydte <mt@waldheinz.de>
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; either version 2.1 of the License, or
+ * (at your option) any later version.
+ *
+ * This library 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 Lesser General Public 
+ * License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; If not, write to the Free Software Foundation, Inc., 
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+ 
+package de.waldheinz.fs;
+
+import java.io.IOException;
+
+/**
+ * Abstract class with common things in different FileSystem implementations.
+ * 
+ * @author Fabien DUMINY
+ * @author Matthias Treydte &lt;waldheinz at gmail.com&gt;
+ */
+public abstract class AbstractFileSystem implements FileSystem {
+    private final boolean readOnly;
+    private boolean closed;
+    
+    /**
+     * Creates a new {@code AbstractFileSystem}.
+     * 
+     * @param readOnly if the file system should be read-only
+     */
+    public AbstractFileSystem(boolean readOnly) {
+        this.closed = false;
+        this.readOnly = readOnly;
+    }
+    
+    @Override
+    public void close() throws IOException {
+        if (!isClosed()) {
+            if (!isReadOnly()) {
+                flush();
+            }
+            
+            closed = true;
+        }
+    }
+    
+    @Override
+    public final boolean isClosed() {
+        return closed;
+    }
+    
+    @Override
+    public final boolean isReadOnly() {
+        return readOnly;
+    }
+
+    /**
+     * Checks if this {@code FileSystem} was already closed, and throws an
+     * exception if it was.
+     *
+     * @throws IllegalStateException if this {@code FileSystem} was
+     *      already closed
+     * @see #isClosed()
+     * @see #close() 
+     */
+    protected final void checkClosed() throws IllegalStateException {
+        if (isClosed()) {
+            throw new IllegalStateException("file system was already closed");
+        }
+    }
+    
+    /**
+     * Checks if this {@code FileSystem} is read-only, and throws an
+     * exception if it is.
+     *
+     * @throws ReadOnlyException if this {@code FileSystem} is read-only
+     * @see #isReadOnly() 
+     */
+    protected final void checkReadOnly() throws ReadOnlyException {
+        if (isReadOnly()) {
+            throw new ReadOnlyException();
+        }
+    }
+}