Reworked DatabaseService API.
Initial implementation of LockManager.
diff --git a/core/api/src/main/java/org/onlab/onos/store/service/DatabaseService.java b/core/api/src/main/java/org/onlab/onos/store/service/DatabaseService.java
index cf0ef0a..57d81f2 100644
--- a/core/api/src/main/java/org/onlab/onos/store/service/DatabaseService.java
+++ b/core/api/src/main/java/org/onlab/onos/store/service/DatabaseService.java
@@ -1,7 +1,5 @@
package org.onlab.onos.store.service;
-import java.util.List;
-
/**
* Service interface for a strongly consistent and durable
* key value data store.
@@ -9,46 +7,93 @@
public interface DatabaseService {
/**
- * Performs a read on the database.
- * @param request read request.
- * @return ReadResult
- * @throws DatabaseException if there is a failure in executing read.
+ * Reads the specified key.
+ * @param tableName name of the table associated with this operation.
+ * @return key key to read.
+ * @returns value (and version) associated with this key. This calls returns null if the key does not exist.
*/
- ReadResult read(ReadRequest request);
-
+ VersionedValue get(String tableName, String key);
+
/**
- * Performs a batch read operation on the database.
- * The main advantage of batch read operation is parallelization.
- * @param batch batch of read requests to execute.
- * @return batch read result.
+ * Associate the key with a value.
+ * @param tableName table name in which this key/value resides.
+ * @param key key with which the specified value is to be associated
+ * @param value value to be associated with the specified key
+ * @return the previous value associated with the specified key, or null if there was no mapping for the key.
*/
- List<OptionalResult<ReadResult, DatabaseException>> batchRead(List<ReadRequest> batch);
-
- // FIXME Give me a better name
+ VersionedValue put(String tableName, String key, byte[] value);
+
/**
- * Performs a write operation on the database.
- * @param request write request
- * @return write result.
- * @throws DatabaseException if there is failure in execution write.
+ * If the specified key is not already associated with a value, associate it with the given value.
+ * @param tableName table name in which this key/value resides.
+ * @param key key with which the specified value is to be associated
+ * @param value value to be associated with the specified key
+ * @return true if put was successful, false if there is already a value associated with this key
*/
- OptionalResult<WriteResult, DatabaseException> writeNothrow(WriteRequest request);
-
+ boolean putIfAbsent(String tableName, String key, byte[] value);
+
/**
- * Performs a write operation on the database.
- * @param request write request
- * @return write result.
- * @throws OptimisticLockException FIXME define conditional failure
- * @throws PreconditionFailedException FIXME define conditional failure
- * @throws DatabaseException if there is failure in execution write.
+ * Sets the key to the specified value if the version in the database (for that key)
+ * matches the specified version.
+ * @param tableName name of table associated with this operation.
+ * @param key key
+ * @param value value
+ * @param version version that should present in the database for the put to be successful.
+ * @return true if put was successful, false if there version in database is different from what is specified.
*/
- WriteResult write(WriteRequest request)/* throws OptimisticLockException, PreconditionFailedException*/;
-
+ boolean putIfVersionMatches(String tableName, String key, byte[] value, long version);
+
/**
- * Performs a batch write operation on the database.
- * Batch write provides transactional semantics. Either all operations
- * succeed or none of them do.
- * @param batch batch of write requests to execute as a transaction.
- * @return result of executing the batch write operation.
+ * Replaces the entry for a key only if currently mapped to a given value.
+ * @param tableName name of table associated with this operation.
+ * @param key with which the specified value is associated
+ * @param oldValue value expected to be associated with the specified key
+ * @param newValue value to be associated with the specified key
+ * @return true if put was successful, false if there version in database is different from what is specified.
*/
- List<OptionalResult<WriteResult, DatabaseException>> batchWrite(List<WriteRequest> batch);
-}
+ boolean putIfValueMatches(String tableName, String key, byte[] oldValue, byte[] newValue);
+
+ /**
+ * Removes the key (and associated value).
+ * @param tableName name of table associated with this operation.
+ * @param key key to remove
+ * @return value previously associated with the key. This call returns null if the key does not exist.
+ */
+ VersionedValue remove(String tableName, String key);
+
+ /**
+ * Removes the key (and associated value) if the version in the database matches specified version.
+ * @param tableName name of table associated with this operation.
+ * @param key key to remove
+ * @param version version that should present in the database for the remove to be successful.
+ * @return true if remove was successful, false if there version in database is different from what is specified.
+ */
+ boolean removeIfVersionMatches(String tableName, String key, long version);
+
+ /**
+ * Removes the key (and associated value) if the value in the database matches specified value.
+ * @param tableName name of table associated with this operation.
+ * @param key key to remove
+ * @param value value that should present in the database for the remove to be successful.
+ * @return true if remove was successful, false if there value in database is different from what is specified.
+ */
+ boolean removeIfValueMatches(String tableName, String key, byte[] value);
+
+ /**
+ * Performs a batch read operation and returns the results.
+ * @param batchRequest batch request.
+ * @return result of the batch operation.
+ */
+ BatchReadResult batchRead(BatchReadRequest batchRequest);
+
+ /**
+ * Performs a batch write operation and returns the results.
+ * This method provides transactional semantics. Either all writes succeed or none do.
+ * Even a single write failure would cause the entire batch to be aborted.
+ * In the case of unsuccessful operation, the batch result can be inspected to determine
+ * which operation(s) caused the batch to fail.
+ * @param batchRequest batch request.
+ * @return result of the batch operation.
+ */
+ BatchWriteResult batchWrite(BatchWriteRequest batchRequest);
+}
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