Quirks.java
/*
* Copyright 2020 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.camera.core.impl;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.RequiresApi;
import java.util.ArrayList;
import java.util.List;
/**
* Wraps a list of {@link Quirk}s, allowing to easily retrieve a {@link Quirk} instance by its
* class.
*/
@RequiresApi(21) // TODO(b/200306659): Remove and replace with annotation on package-info.java
public class Quirks {
@NonNull
private final List<Quirk> mQuirks;
/** Wraps the provided list of quirks. */
public Quirks(@NonNull final List<Quirk> quirks) {
mQuirks = new ArrayList<>(quirks);
}
/**
* Retrieves a {@link Quirk} instance given its type.
*
* <p>Unlike {@link #contains(Class)}, a quirk can only be retrieved by the exact class. If a
* superclass or superinterface is provided, {@code null} will be returned, even if a quirk
* with the provided superclass or superinterface exists in this collection.
*
* @param quirkClass The type of quirk to retrieve.
* @return A {@link Quirk} instance of the provided type, or {@code null} if it isn't found.
*/
@SuppressWarnings("unchecked")
@Nullable
public <T extends Quirk> T get(@NonNull final Class<T> quirkClass) {
for (final Quirk quirk : mQuirks) {
if (quirk.getClass() == quirkClass) {
return (T) quirk;
}
}
return null;
}
/**
* Returns whether this collection of quirks contains a quirk with the provided type.
*
* <p>This checks whether the provided quirk type is the exact class, a superclass, or a
* superinterface of any of the contained quirks, and will return true in all cases.
* @param quirkClass The type of quirk to check for existence in this container.
* @return {@code true} if this container contains a quirk with the given type, {@code false}
* otherwise.
*/
public boolean contains(@NonNull Class<? extends Quirk> quirkClass) {
for (Quirk quirk : mQuirks) {
if (quirkClass.isAssignableFrom(quirk.getClass())) {
return true;
}
}
return false;
}
}