Add retained size to compressor

src/main/java/io/airlift/compress/v3/Compressor.java

@@ -28,4 +28,9 @@ public interface Compressor
      * @return number of bytes written to the output
      */
     int compress(MemorySegment input, MemorySegment output);
+
+    default int getRetainedSizeInBytes(int inputLength)
+    {
+        return 0;
+    }
 }

src/main/java/io/airlift/compress/v3/lz4/Lz4JavaCompressor.java

@@ -69,6 +69,12 @@ public int compress(MemorySegment input, MemorySegment output)
         }
     }
 
+    @Override
+    public int getRetainedSizeInBytes(int inputLength)
+    {
+        return Lz4RawCompressor.computeTableSize(inputLength);
+    }
+
     private static void verifyRange(byte[] data, int offset, int length)
     {
         requireNonNull(data, "data is null");

src/main/java/io/airlift/compress/v3/lz4/Lz4RawCompressor.java

@@ -20,6 +20,7 @@
 import static io.airlift.compress.v3.lz4.Lz4Constants.SIZE_OF_LONG;
 import static io.airlift.compress.v3.lz4.Lz4Constants.SIZE_OF_SHORT;
 import static io.airlift.compress.v3.lz4.UnsafeUtil.UNSAFE;
+import static java.lang.Math.clamp;
 
 final class Lz4RawCompressor
 {
@@ -300,12 +301,12 @@ private static long encodeRunLength(
         return output;
     }
 
-    private static int computeTableSize(int inputSize)
+    static int computeTableSize(int inputSize)
     {
         // smallest power of 2 larger than inputSize
         int target = Integer.highestOneBit(inputSize - 1) << 1;
 
         // keep it between MIN_TABLE_SIZE and MAX_TABLE_SIZE
-        return Math.max(Math.min(target, MAX_TABLE_SIZE), MIN_TABLE_SIZE);
+        return clamp(target, MIN_TABLE_SIZE, MAX_TABLE_SIZE);
     }
 }

src/main/java/io/airlift/compress/v3/lzo/LzoCompressor.java

@@ -71,6 +71,12 @@ public int compress(MemorySegment input, MemorySegment output)
         }
     }
 
+    @Override
+    public int getRetainedSizeInBytes(int inputLength)
+    {
+        return MAX_TABLE_SIZE;
+    }
+
     private static void verifyRange(byte[] data, int offset, int length)
     {
         requireNonNull(data, "data is null");

src/main/java/io/airlift/compress/v3/lzo/LzoRawCompressor.java

@@ -19,6 +19,7 @@
 import static io.airlift.compress.v3.lzo.LzoConstants.SIZE_OF_LONG;
 import static io.airlift.compress.v3.lzo.LzoConstants.SIZE_OF_SHORT;
 import static io.airlift.compress.v3.lzo.UnsafeUtil.UNSAFE;
+import static java.lang.Math.clamp;
 
 final class LzoRawCompressor
 {
@@ -384,6 +385,6 @@ private static int computeTableSize(int inputSize)
         int target = Integer.highestOneBit(inputSize - 1) << 1;
 
         // keep it between MIN_TABLE_SIZE and MAX_TABLE_SIZE
-        return Math.max(Math.min(target, MAX_TABLE_SIZE), MIN_TABLE_SIZE);
+        return clamp(target, MIN_TABLE_SIZE, MAX_TABLE_SIZE);
     }
 }

src/main/java/io/airlift/compress/v3/snappy/SnappyJavaCompressor.java

@@ -75,6 +75,12 @@ public int compress(MemorySegment input, MemorySegment output)
         }
     }
 
+    @Override
+    public int getRetainedSizeInBytes(int inputLength)
+    {
+        return SnappyRawCompressor.getHashTableSize(inputLength);
+    }
+
     private static void verifyRange(byte[] data, int offset, int length)
     {
         requireNonNull(data, "data is null");

src/main/java/io/airlift/compress/v3/snappy/SnappyRawCompressor.java

@@ -21,6 +21,7 @@
 import static io.airlift.compress.v3.snappy.SnappyConstants.SIZE_OF_LONG;
 import static io.airlift.compress.v3.snappy.SnappyConstants.SIZE_OF_SHORT;
 import static io.airlift.compress.v3.snappy.UnsafeUtil.UNSAFE;
+import static java.lang.Math.clamp;
 
 final class SnappyRawCompressor
 {
@@ -344,7 +345,7 @@ private static long emitCopy(Object outputBase, long output, long input, long ma
     }
 
     @SuppressWarnings("IllegalToken")
-    private static int getHashTableSize(int inputSize)
+    static int getHashTableSize(int inputSize)
     {
         // Use smaller hash table when input.size() is smaller, since we
         // fill the table, incurring O(hash table size) overhead for
@@ -356,7 +357,7 @@ private static int getHashTableSize(int inputSize)
         int target = Integer.highestOneBit(inputSize - 1) << 1;
 
         // keep it between MIN_TABLE_SIZE and MAX_TABLE_SIZE
-        return Math.max(Math.min(target, MAX_HASH_TABLE_SIZE), 256);
+        return clamp(target, 256, MAX_HASH_TABLE_SIZE);
     }
 
     // Any hash function will produce a valid compressed stream, but a good

src/main/java/io/airlift/compress/v3/zstd/CompressionContext.java

@@ -15,6 +15,7 @@
 
 import static io.airlift.compress.v3.zstd.Constants.MAX_BLOCK_SIZE;
 import static io.airlift.compress.v3.zstd.Util.checkArgument;
+import static java.lang.Math.clamp;
 
 class CompressionContext
 {
@@ -31,7 +32,7 @@ public CompressionContext(CompressionParameters parameters, long baseAddress, in
     {
         this.parameters = parameters;
 
-        int windowSize = Math.max(1, Math.min(parameters.getWindowSize(), inputSize));
+        int windowSize = clamp(inputSize, 1, parameters.getWindowSize());
         int blockSize = Math.min(MAX_BLOCK_SIZE, windowSize);
         int divider = (parameters.getSearchLength() == 3) ? 3 : 4;
 

src/main/java/io/airlift/compress/v3/zstd/CompressionParameters.java

@@ -18,6 +18,7 @@
 import static io.airlift.compress.v3.zstd.Constants.MIN_WINDOW_LOG;
 import static io.airlift.compress.v3.zstd.Util.cycleLog;
 import static io.airlift.compress.v3.zstd.Util.highestBit;
+import static java.lang.Math.clamp;
 
 class CompressionParameters
 {
@@ -316,7 +317,7 @@ else if (estimatedInputSize <= 256 * 1024) {
         int row = DEFAULT_COMPRESSION_LEVEL;
 
         if (compressionLevel != 0) { // TODO: figure out better way to indicate default compression level
-            row = Math.min(Math.max(0, compressionLevel), MAX_COMPRESSION_LEVEL);
+            row = clamp(compressionLevel, 0, MAX_COMPRESSION_LEVEL);
         }
 
         return DEFAULT_COMPRESSION_PARAMETERS[table][row];