OptionsBundle.java
/*
* Copyright 2019 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 java.util.Collections;
import java.util.Comparator;
import java.util.Map.Entry;
import java.util.Set;
import java.util.TreeMap;
/**
* An immutable implementation of {@link Config}.
*
* <p>OptionsBundle is a collection of {@link Config.Option}s and their values which can be
* queried based on exact {@link Config.Option} objects or based on Option ids.
*/
public class OptionsBundle implements Config {
private static final OptionsBundle EMPTY_BUNDLE =
new OptionsBundle(new TreeMap<>(new Comparator<Option<?>>() {
@Override
public int compare(Option<?> o1, Option<?> o2) {
return o1.getId().compareTo(o2.getId());
}
}));
// TODO: Make these options parcelable
protected final TreeMap<Option<?>, Object> mOptions;
OptionsBundle(TreeMap<Option<?>, Object> options) {
mOptions = options;
}
/**
* Create an OptionsBundle from another configuration.
*
* <p>This will copy the options/values from the provided configuration.
*
* @param otherConfig Configuration containing options/values to be copied.
* @return A new OptionsBundle pre-populated with options/values.
*/
@NonNull
public static OptionsBundle from(@NonNull Config otherConfig) {
// No need to create another instance since OptionsBundle is immutable
if (OptionsBundle.class.equals(otherConfig.getClass())) {
return (OptionsBundle) otherConfig;
}
TreeMap<Option<?>, Object> persistentOptions =
new TreeMap<>(new Comparator<Option<?>>() {
@Override
public int compare(Option<?> o1, Option<?> o2) {
return o1.getId().compareTo(o2.getId());
}
});
for (Option<?> opt : otherConfig.listOptions()) {
persistentOptions.put(opt, otherConfig.retrieveOption(opt));
}
return new OptionsBundle(persistentOptions);
}
/**
* Create an empty OptionsBundle.
*
* <p>This options bundle will have no option/value pairs.
*
* @return An OptionsBundle pre-populated with no options/values.
*/
@NonNull
public static OptionsBundle emptyBundle() {
return EMPTY_BUNDLE;
}
@Override
@NonNull
public Set<Option<?>> listOptions() {
return Collections.unmodifiableSet(mOptions.keySet());
}
@Override
public boolean containsOption(@NonNull Option<?> id) {
return mOptions.containsKey(id);
}
@Override
@Nullable
public <ValueT> ValueT retrieveOption(@NonNull Option<ValueT> id) {
if (!mOptions.containsKey(id)) {
throw new IllegalArgumentException("Option does not exist: " + id);
}
@SuppressWarnings("unchecked")
ValueT value = (ValueT) mOptions.get(id);
return value;
}
@Override
@Nullable
@SuppressWarnings("unchecked")
public <ValueT> ValueT retrieveOption(@NonNull Option<ValueT> id,
@Nullable ValueT valueIfMissing) {
return mOptions.containsKey(id) ? (ValueT) mOptions.get(id) : valueIfMissing;
}
@Override
public void findOptions(@NonNull String idStem, @NonNull OptionMatcher matcher) {
Option<Void> query = Option.create(idStem, Void.class);
for (Entry<Option<?>, Object> entry : mOptions.tailMap(query).entrySet()) {
if (!entry.getKey().getId().startsWith(idStem)) {
// We've reached the end of the range that contains our search stem.
break;
}
Option<?> option = entry.getKey();
if (!matcher.onOptionMatched(option)) {
// Caller does not need further results
break;
}
}
}
}