Fts3.kt
/*
* Copyright 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.room
import androidx.annotation.RequiresApi
import androidx.room.FtsOptions.TOKENIZER_SIMPLE
/**
* Marks an [Entity] annotated class as a FTS3 entity. This class will have a mapping SQLite
* FTS3 table in the database.
*
* [FTS3 and FTS4](https://www.sqlite.org/fts3.html) are SQLite virtual table modules
* that allows full-text searches to be performed on a set of documents.
*
* An FTS entity table always has a column named `rowid` that is the equivalent of an
* `INTEGER PRIMARY KEY` index. Therefore, an FTS entity can only have a single field
* annotated with [PrimaryKey], it must be named `rowid` and must be of
* `INTEGER` affinity. The field can be optionally omitted in the class but can still be
* used in queries.
*
* All fields in an FTS entity are of `TEXT` affinity, except the for the 'rowid' field.
*
* Example:
*
* ```
* @Entity
* @Fts3
* data class Mail (
* @PrimaryKey
* @ColumnInfo(name = "rowid")
* val rowId: Int,
* val subject: String,
* val body: String
* )
* ```
*
* @see [Entity]
* @see [Dao]
* @see [Database]
* @see [PrimaryKey]
* @see [ColumnInfo]
*/
@Target(AnnotationTarget.CLASS)
@Retention(AnnotationRetention.BINARY)
@RequiresApi(16)
public annotation class Fts3(
/**
* The tokenizer to be used in the FTS table.
*
* The default value is [FtsOptions.TOKENIZER_SIMPLE]. Tokenizer arguments can be defined
* with [tokenizerArgs].
*
* If a custom tokenizer is used, the tokenizer and its arguments are not verified at compile
* time.
*
* See [SQLite tokenizers documentation](https://www.sqlite.org/fts3.html#tokenizer) for more
* details.
*
* @return The tokenizer to use on the FTS table. Built-in available tokenizers are
* [FtsOptions.TOKENIZER_SIMPLE], [FtsOptions.TOKENIZER_PORTER] and
* [FtsOptions.TOKENIZER_UNICODE61].
* @see [tokenizerArgs]
*/
val tokenizer: String = TOKENIZER_SIMPLE,
/**
* Optional arguments to configure the defined tokenizer.
* <p>
* Tokenizer arguments consist of an argument name, followed by an "=" character, followed by
* the option value. For example, <code>separators=.</code> defines the dot character as an
* additional separator when using the {@link FtsOptions#TOKENIZER_UNICODE61} tokenizer.
* <p>
* The available arguments that can be defined depend on the tokenizer defined, see the
* [SQLite tokernizers documentation](https://www.sqlite.org/fts3.html#tokenizer) for details.
*
* @return A list of tokenizer arguments strings.
*/
val tokenizerArgs: Array<String> = []
)