1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package androidx.room; 18 19 import java.lang.annotation.ElementType; 20 import java.lang.annotation.Retention; 21 import java.lang.annotation.RetentionPolicy; 22 import java.lang.annotation.Target; 23 24 /** 25 * Specifies additional type converters that Room can use. The TypeConverter is added to the scope 26 * of the element so if you put it on a class / interface, all methods / fields in that class will 27 * be able to use the converters. 28 * <ul> 29 * <li>If you put it on a {@link Database}, all Daos and Entities in that database will be able to 30 * use it. 31 * <li>If you put it on a {@link Dao}, all methods in the Dao will be able to use it. 32 * <li>If you put it on an {@link Entity}, all fields of the Entity will be able to use it. 33 * <li>If you put it on a POJO, all fields of the POJO will be able to use it. 34 * <li>If you put it on an {@link Entity} field, only that field will be able to use it. 35 * <li>If you put it on a {@link Dao} method, all parameters of the method will be able to use it. 36 * <li>If you put it on a {@link Dao} method parameter, just that field will be able to use it. 37 * </ul> 38 * @see TypeConverter 39 */ 40 @Target({ElementType.METHOD, ElementType.PARAMETER, ElementType.TYPE, ElementType.FIELD}) 41 @Retention(RetentionPolicy.CLASS) 42 public @interface TypeConverters { 43 /** 44 * The list of type converter classes. If converter methods are not static, Room will create 45 * an instance of these classes. 46 * 47 * @return The list of classes that contains the converter methods. 48 */ 49 Class<?>[] value(); 50 } 51
