align java ffi library with tidesdb 8 fully, extend test suite

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>com.tidesdb</groupId>
     <artifactId>tidesdb-java</artifactId>
-    <version>0.3.2</version>
+    <version>0.4.0</version>
     <packaging>jar</packaging>
 
     <name>TidesDB Java</name>

src/main/c/com_tidesdb_TidesDB.c

@@ -126,7 +126,7 @@ JNIEXPORT void JNICALL Java_com_tidesdb_TidesDB_nativeCreateColumnFamily(
     jboolean enableBlockIndexes, jint indexSampleRatio, jint blockIndexPrefixLen, jint syncMode,
     jlong syncIntervalUs, jstring comparatorName, jint skipListMaxLevel, jfloat skipListProbability,
     jint defaultIsolationLevel, jlong minDiskSpace, jint l1FileCountTrigger,
-    jint l0QueueStallThreshold)
+    jint l0QueueStallThreshold, jboolean useBtree)
 {
     tidesdb_t *db = (tidesdb_t *)(uintptr_t)handle;
     const char *cfName = (*env)->GetStringUTFChars(env, name, NULL);
@@ -161,7 +161,8 @@ JNIEXPORT void JNICALL Java_com_tidesdb_TidesDB_nativeCreateColumnFamily(
         .default_isolation_level = (tidesdb_isolation_level_t)defaultIsolationLevel,
         .min_disk_space = (uint64_t)minDiskSpace,
         .l1_file_count_trigger = l1FileCountTrigger,
-        .l0_queue_stall_threshold = l0QueueStallThreshold};
+        .l0_queue_stall_threshold = l0QueueStallThreshold,
+        .use_btree = useBtree ? 1 : 0};
 
     memset(config.comparator_name, 0, TDB_MAX_COMPARATOR_NAME);
     if (compName != NULL && strlen(compName) > 0)
@@ -448,13 +449,15 @@ JNIEXPORT jobject JNICALL Java_com_tidesdb_ColumnFamily_nativeGetStats(JNIEnv *e
 
     jclass statsClass = (*env)->FindClass(env, "com/tidesdb/Stats");
     jmethodID constructor = (*env)->GetMethodID(env, statsClass, "<init>",
-                                                "(IJ[J[ILcom/tidesdb/ColumnFamilyConfig;JJDD[JDD)V");
+                                                "(IJ[J[ILcom/tidesdb/ColumnFamilyConfig;JJDD[JDDZJID)V");
 
     jobject statsObj = (*env)->NewObject(env, statsClass, constructor, stats->num_levels,
                                          (jlong)stats->memtable_size, levelSizes, levelNumSSTables,
                                          NULL, (jlong)stats->total_keys, (jlong)stats->total_data_size,
                                          stats->avg_key_size, stats->avg_value_size, levelKeyCounts,
-                                         stats->read_amp, stats->hit_rate);
+                                         stats->read_amp, stats->hit_rate,
+                                         stats->use_btree != 0, (jlong)stats->btree_total_nodes,
+                                         (jint)stats->btree_max_height, stats->btree_avg_height);
 
     tidesdb_free_stats(stats);
 

src/main/java/com/tidesdb/ColumnFamilyConfig.java

@@ -43,6 +43,7 @@ public class ColumnFamilyConfig {
     private long minDiskSpace;
     private int l1FileCountTrigger;
     private int l0QueueStallThreshold;
+    private boolean useBtree;
 
     private ColumnFamilyConfig(Builder builder) {
         this.writeBufferSize = builder.writeBufferSize;
@@ -65,6 +66,7 @@ private ColumnFamilyConfig(Builder builder) {
         this.minDiskSpace = builder.minDiskSpace;
         this.l1FileCountTrigger = builder.l1FileCountTrigger;
         this.l0QueueStallThreshold = builder.l0QueueStallThreshold;
+        this.useBtree = builder.useBtree;
     }
 
     /**
@@ -94,6 +96,7 @@ public static ColumnFamilyConfig defaultConfig() {
             .minDiskSpace(100 * 1024 * 1024)
             .l1FileCountTrigger(4)
             .l0QueueStallThreshold(20)
+            .useBtree(false)
             .build();
     }
 
@@ -126,6 +129,7 @@ public static Builder builder() {
     public long getMinDiskSpace() { return minDiskSpace; }
     public int getL1FileCountTrigger() { return l1FileCountTrigger; }
     public int getL0QueueStallThreshold() { return l0QueueStallThreshold; }
+    public boolean isUseBtree() { return useBtree; }
 
     /**
      * Builder for ColumnFamilyConfig.
@@ -151,6 +155,7 @@ public static class Builder {
         private long minDiskSpace = 100 * 1024 * 1024;
         private int l1FileCountTrigger = 4;
         private int l0QueueStallThreshold = 20;
+        private boolean useBtree = false;
 
         public Builder writeBufferSize(long writeBufferSize) {
             this.writeBufferSize = writeBufferSize;
@@ -252,6 +257,11 @@ public Builder l0QueueStallThreshold(int l0QueueStallThreshold) {
             return this;
         }
 
+        public Builder useBtree(boolean useBtree) {
+            this.useBtree = useBtree;
+            return this;
+        }
+
         public ColumnFamilyConfig build() {
             return new ColumnFamilyConfig(this);
         }

src/main/java/com/tidesdb/Stats.java

@@ -35,11 +35,16 @@ public class Stats {
     private final long[] levelKeyCounts;
     private final double readAmp;
     private final double hitRate;
+    private final boolean useBtree;
+    private final long btreeTotalNodes;
+    private final int btreeMaxHeight;
+    private final double btreeAvgHeight;
 
     public Stats(int numLevels, long memtableSize, long[] levelSizes, int[] levelNumSSTables, 
                  ColumnFamilyConfig config, long totalKeys, long totalDataSize, 
                  double avgKeySize, double avgValueSize, long[] levelKeyCounts,
-                 double readAmp, double hitRate) {
+                 double readAmp, double hitRate, boolean useBtree, long btreeTotalNodes,
+                 int btreeMaxHeight, double btreeAvgHeight) {
         this.numLevels = numLevels;
         this.memtableSize = memtableSize;
         this.levelSizes = levelSizes;
@@ -52,6 +57,10 @@ public Stats(int numLevels, long memtableSize, long[] levelSizes, int[] levelNum
         this.levelKeyCounts = levelKeyCounts;
         this.readAmp = readAmp;
         this.hitRate = hitRate;
+        this.useBtree = useBtree;
+        this.btreeTotalNodes = btreeTotalNodes;
+        this.btreeMaxHeight = btreeMaxHeight;
+        this.btreeAvgHeight = btreeAvgHeight;
     }
 
     /**
@@ -162,6 +171,45 @@ public double getHitRate() {
         return hitRate;
     }
 
+    /**
+     * Returns whether this column family uses B+tree format.
+     *
+     * @return true if B+tree format is used
+     */
+    public boolean isUseBtree() {
+        return useBtree;
+    }
+
+    /**
+     * Gets the total number of B+tree nodes across all SSTables.
+     * Only populated when useBtree is true.
+     *
+     * @return total B+tree nodes
+     */
+    public long getBtreeTotalNodes() {
+        return btreeTotalNodes;
+    }
+
+    /**
+     * Gets the maximum B+tree height across all SSTables.
+     * Only populated when useBtree is true.
+     *
+     * @return maximum tree height
+     */
+    public int getBtreeMaxHeight() {
+        return btreeMaxHeight;
+    }
+
+    /**
+     * Gets the average B+tree height across all SSTables.
+     * Only populated when useBtree is true.
+     *
+     * @return average tree height
+     */
+    public double getBtreeAvgHeight() {
+        return btreeAvgHeight;
+    }
+
     @Override
     public String toString() {
         StringBuilder sb = new StringBuilder();
@@ -173,6 +221,12 @@ public String toString() {
         sb.append(", avgValueSize=").append(avgValueSize);
         sb.append(", readAmp=").append(readAmp);
         sb.append(", hitRate=").append(hitRate);
+        sb.append(", useBtree=").append(useBtree);
+        if (useBtree) {
+            sb.append(", btreeTotalNodes=").append(btreeTotalNodes);
+            sb.append(", btreeMaxHeight=").append(btreeMaxHeight);
+            sb.append(", btreeAvgHeight=").append(btreeAvgHeight);
+        }
         if (levelSizes != null) {
             sb.append(", levelSizes=[");
             for (int i = 0; i < levelSizes.length; i++) {

src/main/java/com/tidesdb/TidesDB.java

@@ -114,7 +114,8 @@ public void createColumnFamily(String name, ColumnFamilyConfig config) throws Ti
             config.getDefaultIsolationLevel().getValue(),
             config.getMinDiskSpace(),
             config.getL1FileCountTrigger(),
-            config.getL0QueueStallThreshold()
+            config.getL0QueueStallThreshold(),
+            config.isUseBtree()
         );
     }
 
@@ -268,7 +269,7 @@ private static native void nativeCreateColumnFamily(long handle, String name,
         double bloomFPR, boolean enableBlockIndexes, int indexSampleRatio, int blockIndexPrefixLen,
         int syncMode, long syncIntervalUs, String comparatorName, int skipListMaxLevel,
         float skipListProbability, int defaultIsolationLevel, long minDiskSpace,
-        int l1FileCountTrigger, int l0QueueStallThreshold) throws TidesDBException;
+        int l1FileCountTrigger, int l0QueueStallThreshold, boolean useBtree) throws TidesDBException;
 
     private static native void nativeDropColumnFamily(long handle, String name) throws TidesDBException;
 

src/test/java/com/tidesdb/TidesDBTest.java

@@ -391,6 +391,13 @@ void testColumnFamilyStats() throws TidesDBException {
             Stats stats = cf.getStats();
             assertNotNull(stats);
             assertTrue(stats.getNumLevels() >= 0);
+            assertTrue(stats.getTotalKeys() >= 0);
+            assertTrue(stats.getTotalDataSize() >= 0);
+            assertTrue(stats.getAvgKeySize() >= 0);
+            assertTrue(stats.getAvgValueSize() >= 0);
+            assertTrue(stats.getReadAmp() >= 0);
+            assertTrue(stats.getHitRate() >= 0.0 && stats.getHitRate() <= 1.0);
+            assertFalse(stats.isUseBtree());
         }
     }
 
@@ -446,6 +453,109 @@ void testCustomColumnFamilyConfig() throws TidesDBException {
 
     @Test
     @Order(13)
+    void testBtreeColumnFamily() throws TidesDBException {
+        Config config = Config.builder(tempDir.resolve("testdb13").toString())
+            .numFlushThreads(2)
+            .numCompactionThreads(2)
+            .logLevel(LogLevel.INFO)
+            .blockCacheSize(64 * 1024 * 1024)
+            .maxOpenSSTables(256)
+            .build();
+
+        try (TidesDB db = TidesDB.open(config)) {
+            ColumnFamilyConfig cfConfig = ColumnFamilyConfig.builder()
+                .writeBufferSize(128 * 1024 * 1024)
+                .levelSizeRatio(10)
+                .minLevels(5)
+                .compressionAlgorithm(CompressionAlgorithm.LZ4_COMPRESSION)
+                .enableBloomFilter(true)
+                .bloomFPR(0.01)
+                .enableBlockIndexes(true)
+                .syncMode(SyncMode.SYNC_FULL)
+                .useBtree(true)
+                .build();
+
+            db.createColumnFamily("btree_cf", cfConfig);
+
+            ColumnFamily cf = db.getColumnFamily("btree_cf");
+            assertNotNull(cf);
+            assertEquals("btree_cf", cf.getName());
+
+            try (Transaction txn = db.beginTransaction()) {
+                for (int i = 0; i < 100; i++) {
+                    txn.put(cf, ("key" + i).getBytes(), ("value" + i).getBytes());
+                }
+                txn.commit();
+            }
+
+            try (Transaction txn = db.beginTransaction()) {
+                byte[] result = txn.get(cf, "key50".getBytes());
+                assertNotNull(result);
+                assertArrayEquals("value50".getBytes(), result);
+            }
+
+            Stats stats = cf.getStats();
+            assertNotNull(stats);
+            assertTrue(stats.isUseBtree());
+            assertTrue(stats.getBtreeTotalNodes() >= 0);
+            assertTrue(stats.getBtreeMaxHeight() >= 0);
+            assertTrue(stats.getBtreeAvgHeight() >= 0.0);
+        }
+    }
+
+    @Test
+    @Order(14)
+    void testBtreeIterator() throws TidesDBException {
+        Config config = Config.builder(tempDir.resolve("testdb14").toString())
+            .numFlushThreads(2)
+            .numCompactionThreads(2)
+            .logLevel(LogLevel.INFO)
+            .blockCacheSize(64 * 1024 * 1024)
+            .maxOpenSSTables(256)
+            .build();
+
+        try (TidesDB db = TidesDB.open(config)) {
+            ColumnFamilyConfig cfConfig = ColumnFamilyConfig.builder()
+                .writeBufferSize(128 * 1024 * 1024)
+                .compressionAlgorithm(CompressionAlgorithm.LZ4_COMPRESSION)
+                .enableBloomFilter(true)
+                .useBtree(true)
+                .build();
+
+            db.createColumnFamily("btree_iter_cf", cfConfig);
+
+            ColumnFamily cf = db.getColumnFamily("btree_iter_cf");
+
+            try (Transaction txn = db.beginTransaction()) {
+                for (int i = 0; i < 10; i++) {
+                    String key = String.format("key%02d", i);
+                    String value = "value" + i;
+                    txn.put(cf, key.getBytes(), value.getBytes());
+                }
+                txn.commit();
+            }
+
+            try (Transaction txn = db.beginTransaction()) {
+                try (TidesDBIterator iter = txn.newIterator(cf)) {
+                    iter.seekToFirst();
+
+                    int count = 0;
+                    while (iter.isValid()) {
+                        byte[] key = iter.key();
+                        byte[] value = iter.value();
+                        assertNotNull(key);
+                        assertNotNull(value);
+                        count++;
+                        iter.next();
+                    }
+                    assertEquals(10, count);
+                }
+            }
+        }
+    }
+
+    @Test
+    @Order(15)
     void testTransactionPutGetDeleteBadKey() throws TidesDBException {
         Config config = Config.builder(tempDir.resolve("testdb3").toString())
                 .numFlushThreads(2)