Java bindings for BG Purge (#6816)

bindings/java/fdbJNI.cpp

@@ -765,6 +765,71 @@ JNIEXPORT jdouble JNICALL Java_com_apple_foundationdb_FDBDatabase_Database_1getM
 	return (jdouble)fdb_database_get_main_thread_busyness(database);
 }
 
+JNIEXPORT jlong JNICALL Java_com_apple_foundationdb_FDBDatabase_Database_1purgeBlobGranules(JNIEnv* jenv,
+                                                                                            jobject,
+                                                                                            jlong dbPtr,
+                                                                                            jbyteArray beginKeyBytes,
+                                                                                            jbyteArray endKeyBytes,
+                                                                                            jlong purgeVersion,
+                                                                                            jboolean force) {
+	if (!dbPtr || !beginKeyBytes || !endKeyBytes) {
+		throwParamNotNull(jenv);
+		return 0;
+	}
+
+	FDBDatabase* database = (FDBDatabase*)dbPtr;
+
+	uint8_t* beginKeyArr = (uint8_t*)jenv->GetByteArrayElements(beginKeyBytes, JNI_NULL);
+	if (!beginKeyArr) {
+		if (!jenv->ExceptionOccurred())
+			throwRuntimeEx(jenv, "Error getting handle to native resources");
+		return 0;
+	}
+
+	uint8_t* endKeyArr = (uint8_t*)jenv->GetByteArrayElements(endKeyBytes, JNI_NULL);
+	if (!endKeyArr) {
+		jenv->ReleaseByteArrayElements(beginKeyBytes, (jbyte*)beginKeyArr, JNI_ABORT);
+		if (!jenv->ExceptionOccurred())
+			throwRuntimeEx(jenv, "Error getting handle to native resources");
+		return 0;
+	}
+
+	FDBFuture* f = fdb_database_purge_blob_granules(database,
+	                                                beginKeyArr,
+	                                                jenv->GetArrayLength(beginKeyBytes),
+	                                                endKeyArr,
+	                                                jenv->GetArrayLength(endKeyBytes),
+	                                                purgeVersion,
+	                                                (fdb_bool_t)force);
+	jenv->ReleaseByteArrayElements(beginKeyBytes, (jbyte*)beginKeyArr, JNI_ABORT);
+	jenv->ReleaseByteArrayElements(endKeyBytes, (jbyte*)endKeyArr, JNI_ABORT);
+	return (jlong)f;
+}
+
+JNIEXPORT jlong JNICALL
+Java_com_apple_foundationdb_FDBDatabase_Database_1waitPurgeGranulesComplete(JNIEnv* jenv,
+                                                                            jobject,
+                                                                            jlong dbPtr,
+                                                                            jbyteArray purgeKeyBytes) {
+	if (!dbPtr || !purgeKeyBytes) {
+		throwParamNotNull(jenv);
+		return 0;
+	}
+	FDBDatabase* database = (FDBDatabase*)dbPtr;
+	uint8_t* purgeKeyArr = (uint8_t*)jenv->GetByteArrayElements(purgeKeyBytes, JNI_NULL);
+
+	if (!purgeKeyArr) {
+		if (!jenv->ExceptionOccurred())
+			throwRuntimeEx(jenv, "Error getting handle to native resources");
+		return 0;
+	}
+	FDBFuture* f =
+	    fdb_database_wait_purge_granules_complete(database, purgeKeyArr, jenv->GetArrayLength(purgeKeyBytes));
+	jenv->ReleaseByteArrayElements(purgeKeyBytes, (jbyte*)purgeKeyArr, JNI_ABORT);
+
+	return (jlong)f;
+}
+
 JNIEXPORT jboolean JNICALL Java_com_apple_foundationdb_FDB_Error_1predicate(JNIEnv* jenv,
                                                                             jobject,
                                                                             jint predicate,

bindings/java/src/main/com/apple/foundationdb/Database.java

@@ -161,6 +161,24 @@ default Transaction createTransaction() {
 	 */
 	double getMainThreadBusyness();
 
+	/**
+	 * Queues a purge of blob granules for the specified key range, at the specified version.
+     *
+	 * @param beginKey start of the key range
+	 * @param endKey end of the key range
+	 * @param purgeVersion version to purge at
+	 * @param force if true delete all data, if not keep data >= purgeVersion
+	 * @return the key to watch for purge complete
+	 */
+	CompletableFuture<byte[]> purgeBlobGranules(byte[] beginKey, byte[] endKey, long purgeVersion, boolean force, Executor e);
+
+	/**
+	 * Wait for a previous call to purgeBlobGranules to complete
+	 *
+	 * @param purgeKey key to watch
+	 */
+	CompletableFuture<Void> waitPurgeGranulesComplete(byte[] purgeKey, Executor e);
+
 	/**
 	 * Runs a read-only transactional function against this {@code Database} with retry logic.
 	 *  {@link Function#apply(Object) apply(ReadTransaction)} will be called on the

bindings/java/src/main/com/apple/foundationdb/FDBDatabase.java

@@ -200,6 +200,26 @@ public double getMainThreadBusyness() {
 		}
 	}
 
+	@Override
+	public CompletableFuture<byte[]> purgeBlobGranules(byte[] beginKey, byte[] endKey, long purgeVersion, boolean force, Executor executor) {
+		pointerReadLock.lock();
+		try {
+			return new FutureKey(Database_purgeBlobGranules(getPtr(), beginKey, endKey, purgeVersion, force), executor, eventKeeper);
+		} finally {
+			pointerReadLock.unlock();
+		}
+	}
+
+	@Override
+	public CompletableFuture<Void> waitPurgeGranulesComplete(byte[] purgeKey, Executor executor) {
+		pointerReadLock.lock();
+		try {
+			return new FutureVoid(Database_waitPurgeGranulesComplete(getPtr(), purgeKey), executor);
+		} finally {
+			pointerReadLock.unlock();
+		}
+	}
+
 	@Override
 	public Executor getExecutor() {
 		return executor;
@@ -215,4 +235,6 @@ protected void closeInternal(long cPtr) {
 	private native void Database_dispose(long cPtr);
 	private native void Database_setOption(long cPtr, int code, byte[] value) throws FDBException;
 	private native double Database_getMainThreadBusyness(long cPtr);
+	private native long Database_purgeBlobGranules(long cPtr, byte[] beginKey, byte[] endKey, long purgeVersion, boolean force);
+	private native long Database_waitPurgeGranulesComplete(long cPtr, byte[] purgeKey);
 }