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diff --git a/src/main/java/org/openslx/virtualization/disk/DiskImage.java b/src/main/java/org/openslx/virtualization/disk/DiskImage.java
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+++ b/src/main/java/org/openslx/virtualization/disk/DiskImage.java
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+package org.openslx.virtualization.disk;
+
+import java.io.Closeable;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+import java.util.List;
+import java.util.function.Predicate;
+
+import org.openslx.bwlp.thrift.iface.Virtualizer;
+import org.openslx.thrifthelper.TConst;
+import org.openslx.util.Util;
+import org.openslx.virtualization.Version;
+
+/**
+ * Disk image for virtual machines.
+ * 
+ * @implNote This class is the abstract base class to implement various specific disk images (like
+ *           QCOW2 or VMDK).
+ * 
+ * @author Manuel Bentele
+ * @version 1.0
+ */
+public abstract class DiskImage implements Closeable
+{
+	/**
+	 * Stores the image file of the disk.
+	 */
+	private RandomAccessFile diskImage = null;
+
+	/**
+	 * Creates a new disk image from an existing image file with a known disk image format.
+	 * 
+	 * @param diskImage file to a disk storing the image content.
+	 * 
+	 * @implNote Do not use this constructor to create a new disk image from an image file with
+	 *           unknown disk image format. Instead, use the factory method
+	 *           {@link #newInstance(File)} to probe unknown disk image files before creation.
+	 */
+	protected DiskImage( RandomAccessFile diskImage )
+	{
+		this.diskImage = diskImage;
+	}
+
+	/**
+	 * Returns the disk image file.
+	 * 
+	 * @return the disk image file.
+	 */
+	protected RandomAccessFile getDiskImage()
+	{
+		return this.diskImage;
+	}
+
+	/**
+	 * Checks whether disk image is standalone and do not depend on other files (e.g. snapshot
+	 * files).
+	 * 
+	 * @return state whether disk image is standalone or not.
+	 * 
+	 * @throws DiskImageException unable to check if disk image is standalone.
+	 */
+	public abstract boolean isStandalone() throws DiskImageException;
+
+	/**
+	 * Checks whether disk image is compressed.
+	 * 
+	 * @return state whether disk image is compressed or not.
+	 * 
+	 * @throws DiskImageException unable to check whether disk image is compressed.
+	 */
+	public abstract boolean isCompressed() throws DiskImageException;
+
+	/**
+	 * Checks whether disk image is a snapshot.
+	 * 
+	 * @return state whether disk image is a snapshot or not.
+	 * 
+	 * @throws DiskImageException unable to check whether disk image is a snapshot.
+	 */
+	public abstract boolean isSnapshot() throws DiskImageException;
+
+	/**
+	 * Returns the version of the disk image format.
+	 * 
+	 * @return version of the disk image format.
+	 * 
+	 * @throws DiskImageException unable to obtain version of the disk image format.
+	 */
+	public abstract Version getVersion() throws DiskImageException;
+
+	/**
+	 * Returns the disk image description.
+	 * 
+	 * @return description of the disk image.
+	 * 
+	 * @throws DiskImageException unable to obtain description of the disk image.
+	 */
+	public abstract String getDescription() throws DiskImageException;
+
+	/**
+	 * Returns the format of the disk image.
+	 * 
+	 * @return format of the disk image.
+	 */
+	public abstract ImageFormat getFormat();
+
+	/**
+	 * Creates a new disk image from an existing image file with an unknown disk image format.
+	 * 
+	 * @param diskImagePath file to a disk storing the image content.
+	 * @return concrete disk image instance.
+	 * 
+	 * @throws FileNotFoundException cannot find specified disk image file.
+	 * @throws IOException cannot access the content of the disk image file.
+	 * @throws DiskImageException disk image file has an invalid and unknown disk image format.
+	 */
+	public static DiskImage newInstance( File diskImagePath )
+			throws FileNotFoundException, IOException, DiskImageException
+	{
+		// Make sure this doesn't escape the scope, in case instantiation fails - we can't know when the GC
+		// would come along and close this file, which is problematic on Windows (blocking rename/delete)
+		final RandomAccessFile fileHandle = new RandomAccessFile( diskImagePath, "r" );
+
+		try {
+			if ( DiskImageQcow2.probe( fileHandle ) ) {
+				return new DiskImageQcow2( fileHandle );
+			} else if ( DiskImageVdi.probe( fileHandle ) ) {
+				return new DiskImageVdi( fileHandle );
+			} else if ( DiskImageVmdk.probe( fileHandle ) ) {
+				return new DiskImageVmdk( fileHandle );
+			}
+		} catch ( Exception e ) {
+			Util.safeClose( fileHandle );
+			throw e;
+		}
+		Util.safeClose( fileHandle );
+		final String errorMsg = "File '" + diskImagePath.getAbsolutePath() + "' is not a valid disk image!";
+		throw new DiskImageException( errorMsg );
+	}
+
+	@Override
+	public void close() throws IOException
+	{
+		Util.safeClose( diskImage );
+	}
+
+	@Override
+	protected void finalize() throws Throwable
+	{
+		close();
+	}
+
+	/**
+	 * Format of a disk image.
+	 * 
+	 * @author Manuel Bentele
+	 * @version 1.0
+	 */
+	public enum ImageFormat
+	{
+		// @formatter:off
+		NONE ( "none" ),
+		QCOW2( "qcow2" ),
+		VDI  ( "vdi" ),
+		VMDK ( "vmdk" );
+		// @formatter:on
+
+		/**
+		 * Stores filename extension of the disk image format.
+		 */
+		public final String extension;
+
+		/**
+		 * Create new disk image format.
+		 * 
+		 * @param extension filename extension of the disk image format.
+		 */
+		ImageFormat( String extension )
+		{
+			this.extension = extension;
+		}
+
+		/**
+		 * Returns filename extension of the disk image.
+		 * 
+		 * @return filename extension of the disk image.
+		 */
+		public String getExtension()
+		{
+			return this.extension;
+		}
+
+		/**
+		 * Checks if the disk image format is supported by a virtualizer.
+		 * 
+		 * @param supportedImageFormats list of supported disk image formats of a virtualizer.
+		 * @return <code>true</code> if image type is supported by the virtualizer; otherwise
+		 *         <code>false</code>.
+		 */
+		public boolean isSupportedbyVirtualizer( List<ImageFormat> supportedImageFormats )
+		{
+			Predicate<ImageFormat> matchDiskFormat = supportedImageFormat -> supportedImageFormat.toString()
+					.equalsIgnoreCase( this.toString() );
+			return supportedImageFormats.stream().anyMatch( matchDiskFormat );
+		}
+
+		/**
+		 * Returns default (preferred) disk image format for the specified virtualizer.
+		 * 
+		 * @param virt virtualizer for that the default disk image should be determined.
+		 * @return default (preferred) disk image format.
+		 */
+		public static ImageFormat defaultForVirtualizer( Virtualizer virt )
+		{
+			if ( virt == null ) {
+				return null;
+			} else {
+				return ImageFormat.defaultForVirtualizer( virt.virtId );
+			}
+		}
+
+		/**
+		 * Returns default (preferred) disk image format for the specified virtualizer.
+		 * 
+		 * @param virtId ID of a virtualizer for that the default disk image should be determined.
+		 * @return default (preferred) disk image format.
+		 */
+		public static ImageFormat defaultForVirtualizer( String virtId )
+		{
+			ImageFormat imgFormat = null;
+
+			if ( TConst.VIRT_DOCKER.equals( virtId ) ) {
+				imgFormat = NONE;
+			} else if ( TConst.VIRT_QEMU.equals( virtId ) ) {
+				imgFormat = QCOW2;
+			} else if ( TConst.VIRT_VIRTUALBOX.equals( virtId ) ) {
+				imgFormat = VDI;
+			} else if ( TConst.VIRT_VMWARE.equals( virtId ) ) {
+				imgFormat = VMDK;
+			}
+
+			return imgFormat;
+		}
+
+		@Override
+		public String toString()
+		{
+			return this.getExtension();
+		}
+	}
+}