Add method to load all available cache files.

This method look for all available codebooks. Those codebooks differ only in its size. The quantization type (and also quantization vector) is equal in all found cache files.

src/main/java/azgracompress/cache/QuantizationCacheManager.java

@@ -7,6 +7,7 @@ import azgracompress.quantization.scalar.SQCodebook;
 import azgracompress.quantization.vector.VQCodebook;
 
 import java.io.*;
+import java.util.ArrayList;
 
 
 public class QuantizationCacheManager {
@@ -54,7 +55,7 @@ public class QuantizationCacheManager {
         final File inputFile = new File(trainFile);
         final String cacheFileName = String.format("%s_%d_%dx%dx%d.qvc", inputFile.getName(), codebookSize,
                                                    vDim.getX(), vDim.getY(), vDim.getZ());
-//         System.out.println("getCacheFilePathForVQ()=" + cacheFileName);
+        //         System.out.println("getCacheFilePathForVQ()=" + cacheFileName);
         return new File(cacheFolder, cacheFileName);
     }
 
@@ -286,6 +287,39 @@ public class QuantizationCacheManager {
         return null;
     }
 
+
+    /**
+     * Tries to load all (different codebook sizes) available cache files for given file and quantization type.
+     *
+     * @param compressionParams Parameters used to find cache file.
+     * @return Cache files which are available for given file and quantization type.
+     */
+    public ArrayList<ICacheFile> loadAvailableCacheFiles(final CompressionOptions compressionParams) {
+        final ArrayList<ICacheFile> availableCacheFiles = new ArrayList<>();
+
+        final int originalBPCI = compressionParams.getBitsPerCodebookIndex();
+        try {
+
+            for (int bpci = 2; bpci < 9; bpci++) { // 2 to 8
+                compressionParams.setBitsPerCodebookIndex(bpci);
+                final ICacheFile bpciCacheFile = loadCacheFile(compressionParams);
+                if (bpciCacheFile != null) {
+                    availableCacheFiles.add(bpciCacheFile);
+                }
+            }
+        } finally {
+            compressionParams.setBitsPerCodebookIndex(originalBPCI);
+        }
+        return availableCacheFiles;
+    }
+
+    /**
+     * Tries to load cache file for specified file and quantization type. Also Bits Per Codebook index and quantization vector dimensions
+     * are used when searching for given cache file.
+     *
+     * @param compressionParams Parameters used to find cache file.
+     * @return Quantization cache file or null if requested file doesn't exist.
+     */
     public ICacheFile loadCacheFile(final CompressionOptions compressionParams) {
         final String path;
         final int codebookSize = (int) Math.pow(2, compressionParams.getBitsPerCodebookIndex());