Add RocksDB.destroyColumnFamilyHandle() method

facebook · Oct 14, 2020 · d152856 · d152856
1 parent b09308b
commit d152856
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Showing 2 changed files with 41 additions and 6 deletions.
diff --git a/java/src/main/java/org/rocksdb/RocksDB.java b/java/src/main/java/org/rocksdb/RocksDB.java
@@ -780,7 +780,22 @@ public void dropColumnFamilies(
     dropColumnFamilies(nativeHandle_, cfHandles);
   }
 
-  //TODO(AR) what about DestroyColumnFamilyHandle
+  /**
+   * Deletes native column family handle of given {@link ColumnFamilyHandle} Java object
+   * and removes reference from {@link RocksDB#ownedColumnFamilyHandles}.
+   *
+   * @param columnFamilyHandle column family handle object.
+   */
+  public void destroyColumnFamilyHandle(final ColumnFamilyHandle columnFamilyHandle) {
+    for (int i = 0; i < ownedColumnFamilyHandles.size(); ++i) {
+      final ColumnFamilyHandle ownedHandle = ownedColumnFamilyHandles.get(i);
+      if (ownedHandle.equals(columnFamilyHandle)) {
+        columnFamilyHandle.close();
+        ownedColumnFamilyHandles.remove(i);
+        return;
+      }
+    }
+  }
 
   /**
    * Set the database entry for "key" to "value".
@@ -4506,7 +4521,6 @@ private native void dropColumnFamily(
       final long handle, final long cfHandle) throws RocksDBException;
   private native void dropColumnFamilies(final long handle,
       final long[] cfHandles) throws RocksDBException;
-  //TODO(AR) best way to express DestroyColumnFamilyHandle? ...maybe in ColumnFamilyHandle?
   private native void put(final long handle, final byte[] key,
       final int keyOffset, final int keyLength, final byte[] value,
       final int valueOffset, int valueLength) throws RocksDBException;

diff --git a/java/src/test/java/org/rocksdb/ColumnFamilyTest.java b/java/src/test/java/org/rocksdb/ColumnFamilyTest.java
@@ -5,16 +5,17 @@
 
 package org.rocksdb;
 
-import java.util.*;
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 
+import java.util.*;
 import org.junit.ClassRule;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
 
-import static java.nio.charset.StandardCharsets.UTF_8;
-import static org.assertj.core.api.Assertions.assertThat;
-
 public class ColumnFamilyTest {
 
   @ClassRule
@@ -559,6 +560,26 @@ public void testCFNameSimplifiedChinese() throws RocksDBException {
     }
   }
 
+  @Test
+  public void testDestroyColumnFamilyHandle() throws RocksDBException {
+    try (final Options options = new Options().setCreateIfMissing(true);
+         final RocksDB db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath());) {
+      final byte[] name1 = "cf1".getBytes();
+      final byte[] name2 = "cf2".getBytes();
+      final ColumnFamilyDescriptor desc1 = new ColumnFamilyDescriptor(name1);
+      final ColumnFamilyDescriptor desc2 = new ColumnFamilyDescriptor(name2);
+      final ColumnFamilyHandle cf1 = db.createColumnFamily(desc1);
+      final ColumnFamilyHandle cf2 = db.createColumnFamily(desc2);
+      assertTrue(cf1.isOwningHandle());
+      assertTrue(cf2.isOwningHandle());
+      assertFalse(cf1.isDefaultColumnFamily());
+      db.destroyColumnFamilyHandle(cf1);
+      // At this point cf1 should not be used!
+      assertFalse(cf1.isOwningHandle());
+      assertTrue(cf2.isOwningHandle());
+    }
+  }
+
   @Test
   @Deprecated
   /**