ThreadFactoryBuilder.java
/*
* Copyright (C) 2022 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.test.espresso.util.concurrent;
import static androidx.test.internal.util.Checks.checkNotNull;
import androidx.annotation.RestrictTo;
import androidx.annotation.RestrictTo.Scope;
import java.util.Locale;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicLong;
/**
* A minimal implementation of Guava's ThreadFactoryBuilder
*
* @hide
*/
@RestrictTo(Scope.LIBRARY)
public class ThreadFactoryBuilder {
private String nameFormat;
public ThreadFactoryBuilder setNameFormat(String nameFormat) {
String unused = format(nameFormat, 0); // fail fast if the format is bad or null
this.nameFormat = nameFormat;
return this;
}
public ThreadFactory build() {
// espresso usages currently always set nameFormat, so lets just assert its nonnull to
// simplify logic
checkNotNull(nameFormat);
ThreadFactory backingFactory = Executors.defaultThreadFactory();
AtomicLong count = new AtomicLong(0);
return r -> {
Thread thread = backingFactory.newThread(r);
thread.setName(format(nameFormat, count.getAndIncrement()));
return thread;
};
}
private static String format(String format, Object... args) {
return String.format(Locale.ROOT, format, args);
}
}