androidx/room/Dao.java

/*
 * Copyright (C) 2016 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 java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Marks the class as a Data Access Object.
 * <p>
 * Data Access Objects are the main classes where you define your database interactions. They can
 * include a variety of query methods.
 * <p>
 * The class marked with {@code @Dao} should either be an interface or an abstract class. At compile
 * time, Room will generate an implementation of this class when it is referenced by a
 * {@link Database}.
 * <p>
 * An abstract {@code @Dao} class can optionally have a constructor that takes a {@link Database}
 * as its only parameter.
 * <p>
 * It is recommended to have multiple {@code Dao} classes in your codebase depending on the tables
 * they touch.
 *
 * @see Query
 * @see Delete
 * @see Insert
 */
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.CLASS)
public @interface Dao {
}