refactored internal helper classes for hash tables

Author: cicirello

src/org/cicirello/sequences/distance/KendallTauSequenceDistance.java

@@ -812,13 +812,13 @@ static final class Node {
 		}
 	}
 
-	private static final class IntHT {
+	static class BaseHT {
+		private final int MAX_SIZE;
+		protected final int mask;
+		protected final int minSize;
 
-		private Node[] table;
-		private static final int MAX_SIZE = 0x40000000;
-		private int mask;
-		
-		IntHT(int minSize) {
+		BaseHT(int maxSize, int minSize) {
+			MAX_SIZE = maxSize;
 			if (minSize > MAX_SIZE) {
 				minSize = MAX_SIZE;
 				mask = minSize - 1;
@@ -832,6 +832,16 @@ private static final class IntHT {
 				mask = minSize;
 				minSize++;
 			}
+			this.minSize = minSize;
+		}
+	}
+	
+	private static final class IntHT extends BaseHT {
+		
+		private final Node[] table;
+		
+		IntHT(int min) {
+			super(0x40000000, min);
 			table = new Node[minSize];
 		}
 
@@ -872,26 +882,12 @@ static final class Node {
 		}
 	}
 
-	private static final class LongHT {
+	private static final class LongHT extends BaseHT {
 
-		private Node[] table;
-		private static final int MAX_SIZE = 0x40000000;
-		private int mask;
+		private final Node[] table;
 
-		LongHT(int minSize) {
-			if (minSize > MAX_SIZE) {
-				minSize = MAX_SIZE;
-				mask = minSize - 1;
-			} else {
-				minSize = minSize - 1;
-				minSize = minSize | (minSize >> 1);
-				minSize = minSize | (minSize >> 2);
-				minSize = minSize | (minSize >> 4);
-				minSize = minSize | (minSize >> 8);
-				minSize = minSize | (minSize >> 16);
-				mask = minSize;
-				minSize++;
-			}
+		LongHT(int min) {
+			super(0x40000000, min);
 			table = new Node[minSize];
 		}
 
@@ -933,26 +929,12 @@ static final class Node {
 		}
 	}
 
-	private static final class ShortHT {
+	private static final class ShortHT extends BaseHT {
 
-		private Node[] table;
-		private static final int MAX_SIZE = 0x10000;
-		private int mask;
+		private final Node[] table;
 
-		ShortHT(int minSize) {
-			if (minSize > MAX_SIZE) {
-				minSize = MAX_SIZE;
-				mask = minSize - 1;
-			} else {
-				minSize = minSize - 1;
-				minSize = minSize | (minSize >> 1);
-				minSize = minSize | (minSize >> 2);
-				minSize = minSize | (minSize >> 4);
-				minSize = minSize | (minSize >> 8);
-				minSize = minSize | (minSize >> 16);
-				mask = minSize;
-				minSize++;
-			}
+		ShortHT(int min) {
+			super(0x10000, min);
 			table = new Node[minSize];
 		}
 
@@ -993,26 +975,12 @@ static final class Node {
 		}
 	}
 
-	private static final class CharHT {
+	private static final class CharHT extends BaseHT {
 
-		private Node[] table;
-		private static final int MAX_SIZE = 0x10000;
-		private int mask;
+		private final Node[] table;
 
-		CharHT(int minSize) {
-			if (minSize > MAX_SIZE) {
-				minSize = MAX_SIZE;
-				mask = minSize - 1;
-			} else {
-				minSize = minSize - 1;
-				minSize = minSize | (minSize >> 1);
-				minSize = minSize | (minSize >> 2);
-				minSize = minSize | (minSize >> 4);
-				minSize = minSize | (minSize >> 8);
-				minSize = minSize | (minSize >> 16);
-				mask = minSize;
-				minSize++;
-			}
+		CharHT(int min) {
+			super(0x10000, min);
 			table = new Node[minSize];
 		}
 
@@ -1053,26 +1021,12 @@ static final class Node {
 		}
 	}
 
-	private static final class DoubleHT {
+	private static final class DoubleHT extends BaseHT {
 
-		private Node[] table;
-		private static final int MAX_SIZE = 0x40000000;
-		private int mask;
+		private final Node[] table;
 
-		DoubleHT(int minSize) {
-			if (minSize > MAX_SIZE) {
-				minSize = MAX_SIZE;
-				mask = minSize - 1;
-			} else {
-				minSize = minSize - 1;
-				minSize = minSize | (minSize >> 1);
-				minSize = minSize | (minSize >> 2);
-				minSize = minSize | (minSize >> 4);
-				minSize = minSize | (minSize >> 8);
-				minSize = minSize | (minSize >> 16);
-				mask = minSize;
-				minSize++;
-			}
+		DoubleHT(int min) {
+			super(0x40000000, min);
 			table = new Node[minSize];
 		}
 
@@ -1115,26 +1069,12 @@ static final class Node {
 		}
 	}
 
-	private static final class FloatHT {
+	private static final class FloatHT extends BaseHT {
 
-		private Node[] table;
-		private static final int MAX_SIZE = 0x40000000;
-		private int mask;
+		private final Node[] table;
 
-		FloatHT(int minSize) {
-			if (minSize > MAX_SIZE) {
-				minSize = MAX_SIZE;
-				mask = minSize - 1;
-			} else {
-				minSize = minSize - 1;
-				minSize = minSize | (minSize >> 1);
-				minSize = minSize | (minSize >> 2);
-				minSize = minSize | (minSize >> 4);
-				minSize = minSize | (minSize >> 8);
-				minSize = minSize | (minSize >> 16);
-				mask = minSize;
-				minSize++;
-			}
+		FloatHT(int min) {
+			super(0x40000000, min);
 			table = new Node[minSize];
 		}