1 files changed, 8 insertions, 0 deletions
diff --git a/vespajlib/src/main/java/com/yahoo/compress/IntegerCompressor.java b/vespajlib/src/main/java/com/yahoo/compress/IntegerCompressor.java
index fada7243b95..42178fa3ffd 100644
--- a/vespajlib/src/main/java/com/yahoo/compress/IntegerCompressor.java
+++ b/vespajlib/src/main/java/com/yahoo/compress/IntegerCompressor.java
@@ -10,6 +10,14 @@ import java.nio.ByteBuffer;
  */
 public class IntegerCompressor {
 
+    public enum Mode { NONE, COMPRESSED, COMPRESSED_POSITIVE; }
+
+    public static Mode compressionMode(int min, int max) {
+        if (min >= 0 && max < 1 << 30) return Mode.COMPRESSED_POSITIVE;
+        if (min > -1 << 29 && max < 1 << 29) return Mode.COMPRESSED;
+        return Mode.NONE;
+    }
+
     public static void putCompressedNumber(int n, ByteBuffer buf) {
         int negative = n < 0 ? 0x80 : 0x0;
         if (negative != 0) {