Used the try with resource block.

src/main/java/azgracompress/DataCompressor.java

@@ -41,12 +41,8 @@ public class DataCompressor {
 
             case Compress: {
                 ImageCompressor compressor = new ImageCompressor(parsedCliOptions);
-                try {
-                    compressor.compress();
-                } catch (Exception e) {
+                if (!compressor.compress()) {
                     System.err.println("Errors occurred during compression.");
-                    System.err.println(e.getMessage());
-                    e.printStackTrace();
                 }
                 return;
             }

src/main/java/azgracompress/cli/ParsedCliOptions.java

@@ -430,6 +430,11 @@ public class ParsedCliOptions {
         return sb.toString();
     }
 
+    /**
+     * Get number of planes to be compressed.
+     *
+     * @return Number of planes for compression.
+     */
     public int getNumberOfPlanes() {
         if (hasPlaneIndexSet()) {
             return 1;

src/main/java/azgracompress/compression/IImageCompressor.java

+package azgracompress.compression;
+
+import java.io.DataOutputStream;
+
+public interface IImageCompressor {
+
+    // TODO(Moravec): Replace default Exception with better Exception type.
+    void compress(DataOutputStream compressStream) throws Exception;
+}

src/main/java/azgracompress/compression/ImageCompressor.java

@@ -3,9 +3,7 @@ package azgracompress.compression;
 import azgracompress.cli.ParsedCliOptions;
 import azgracompress.fileformat.QCMPFileHeader;
 
-import java.io.BufferedOutputStream;
-import java.io.DataOutputStream;
-import java.io.FileOutputStream;
+import java.io.*;
 
 public class ImageCompressor extends CompressorDecompressorBase {
 
@@ -16,44 +14,57 @@ public class ImageCompressor extends CompressorDecompressorBase {
         codebookSize = (int) Math.pow(2, options.getBitsPerPixel());
     }
 
-
-    public void compress() throws Exception {
-
-        Log(String.format("Compression with BPP = %d", options.getBitsPerPixel()));
-
-        FileOutputStream fos = new FileOutputStream(options.getOutputFile(), false);
-        DataOutputStream compressStream = new DataOutputStream(new BufferedOutputStream(fos, 8192));
-
-        // Create and write header to output stream.
-        final QCMPFileHeader header = createHeader();
-        header.writeHeader(compressStream);
-
-        boolean compressionResult = true;
+    /**
+     * Create compressor based on set options.
+     *
+     * @return Correct implementation of image compressor or null if configuration is not valid.
+     */
+    private IImageCompressor getImageCompressor() {
         switch (options.getQuantizationType()) {
             case Scalar: {
-                SQImageCompressor compressor = new SQImageCompressor(options);
-                compressor.compress(compressStream);
+                return new SQImageCompressor(options);
             }
-            break;
             case Vector1D:
             case Vector2D: {
-                VQImageCompressor compressor = new VQImageCompressor(options);
-                compressor.compress(compressStream);
+                return new VQImageCompressor(options);
             }
-            break;
             case Vector3D:
             case Invalid:
-                throw new Exception("Not supported quantization type");
+            default:
+                return null;
+        }
+    }
+
+
+    public boolean compress() {
+        IImageCompressor imageCompressor = getImageCompressor();
+
+        if (imageCompressor == null) {
+            return false;
         }
 
-        compressStream.flush();
-        fos.flush();
+        try (FileOutputStream fos = new FileOutputStream(options.getOutputFile(), false);
+             DataOutputStream compressStream = new DataOutputStream(new BufferedOutputStream(fos, 8192))) {
+
+            final QCMPFileHeader header = createHeader();
+            header.writeHeader(compressStream);
+
+            imageCompressor.compress(compressStream);
+
+        } catch (Exception ex) {
+            System.err.println(ex.getMessage());
+            return false;
 
-        compressStream.close();
-        fos.close();
+        }
+        return true;
     }
 
 
+    /**
+     * Create QCMPFile header for compressed file.
+     *
+     * @return Valid QCMPFile header for compressed file.
+     */
     private QCMPFileHeader createHeader() {
         QCMPFileHeader header = new QCMPFileHeader();
 
@@ -65,15 +76,8 @@ public class ImageCompressor extends CompressorDecompressorBase {
         header.setImageSizeY(options.getImageDimension().getY());
         header.setImageSizeZ(options.getNumberOfPlanes());
 
-        // If plane index is set then, we are compressing only one plane.
-        if (options.hasPlaneIndexSet()) {
-            header.setImageSizeZ(1);
-        }
-
         header.setVectorDimension(options.getVectorDimension());
 
         return header;
     }
-
-
 }

src/main/java/azgracompress/compression/SQImageCompressor.java

@@ -11,7 +11,7 @@ import azgracompress.quantization.scalar.ScalarQuantizer;
 import java.io.DataOutputStream;
 import java.io.IOException;
 
-public class SQImageCompressor extends CompressorDecompressorBase {
+public class SQImageCompressor extends CompressorDecompressorBase implements IImageCompressor {
 
     public SQImageCompressor(ParsedCliOptions options) {
         super(options);

src/main/java/azgracompress/compression/VQImageCompressor.java

@@ -14,7 +14,7 @@ import azgracompress.quantization.vector.VectorQuantizer;
 import java.io.DataOutputStream;
 import java.io.IOException;
 
-public class VQImageCompressor extends CompressorDecompressorBase {
+public class VQImageCompressor extends CompressorDecompressorBase implements IImageCompressor {
 
     public VQImageCompressor(ParsedCliOptions options) {
         super(options);