diff --git a/paimon-common/src/main/java/org/apache/paimon/utils/BloomFilter.java b/paimon-common/src/main/java/org/apache/paimon/utils/BloomFilter.java
index acd4b3050de7..1cfab654dd49 100644
--- a/paimon-common/src/main/java/org/apache/paimon/utils/BloomFilter.java
+++ b/paimon-common/src/main/java/org/apache/paimon/utils/BloomFilter.java
@@ -26,17 +26,20 @@
 /** Bloom filter based on one memory segment. */
 public class BloomFilter {
 
-    protected BitSet bitSet;
-    protected long expectedEntries;
-    protected int numHashFunctions;
+    private final BitSet bitSet;
+    private final int numHashFunctions;
 
     public BloomFilter(long expectedEntries, int byteSize) {
         checkArgument(expectedEntries > 0, "expectedEntries should be > 0");
-        this.expectedEntries = expectedEntries;
         this.numHashFunctions = optimalNumOfHashFunctions(expectedEntries, (long) byteSize << 3);
         this.bitSet = new BitSet(byteSize);
     }
 
+    @VisibleForTesting
+    int numHashFunctions() {
+        return numHashFunctions;
+    }
+
     public void setMemorySegment(MemorySegment memorySegment, int offset) {
         this.bitSet.setMemorySegment(memorySegment, offset);
     }
diff --git a/paimon-common/src/test/java/org/apache/paimon/utils/BloomFilterTest.java b/paimon-common/src/test/java/org/apache/paimon/utils/BloomFilterTest.java
index a4c0f46dcf38..2c67f41e6852 100644
--- a/paimon-common/src/test/java/org/apache/paimon/utils/BloomFilterTest.java
+++ b/paimon-common/src/test/java/org/apache/paimon/utils/BloomFilterTest.java
@@ -46,19 +46,19 @@ public void testOneSegmentBuilder() {
 
     @Test
     public void testEstimatedHashFunctions() {
-        Assertions.assertThat(BloomFilter.builder(1000, 0.01).getFilter().numHashFunctions)
+        Assertions.assertThat(BloomFilter.builder(1000, 0.01).getFilter().numHashFunctions())
                 .isEqualTo(7);
-        Assertions.assertThat(BloomFilter.builder(10_000, 0.01).getFilter().numHashFunctions)
+        Assertions.assertThat(BloomFilter.builder(10_000, 0.01).getFilter().numHashFunctions())
                 .isEqualTo(7);
-        Assertions.assertThat(BloomFilter.builder(100_000, 0.01).getFilter().numHashFunctions)
+        Assertions.assertThat(BloomFilter.builder(100_000, 0.01).getFilter().numHashFunctions())
                 .isEqualTo(7);
-        Assertions.assertThat(BloomFilter.builder(100_000, 0.01).getFilter().numHashFunctions)
+        Assertions.assertThat(BloomFilter.builder(100_000, 0.01).getFilter().numHashFunctions())
                 .isEqualTo(7);
-        Assertions.assertThat(BloomFilter.builder(100_000, 0.05).getFilter().numHashFunctions)
+        Assertions.assertThat(BloomFilter.builder(100_000, 0.05).getFilter().numHashFunctions())
                 .isEqualTo(4);
-        Assertions.assertThat(BloomFilter.builder(1_000_000, 0.01).getFilter().numHashFunctions)
+        Assertions.assertThat(BloomFilter.builder(1_000_000, 0.01).getFilter().numHashFunctions())
                 .isEqualTo(7);
-        Assertions.assertThat(BloomFilter.builder(1_000_000, 0.05).getFilter().numHashFunctions)
+        Assertions.assertThat(BloomFilter.builder(1_000_000, 0.05).getFilter().numHashFunctions())
                 .isEqualTo(4);
     }