Java ThreadFactory如何为JUnit中的测试创建ThreadCreationException

尝试使用ThreadFactory创建单元测试（边界集成测试），只是想知道如何“强制”Java/JVM不能创建更多线程

换句话说，如何调用ThreadFactory.newThread并获取null

import org.jboss.threads.JBossThreadFactory.JBossThreadFactory;  
import java.util.concurrent.ThreadFactory;

private final ThreadFactory threadFactory;

JBossThreadFactory threadFactory = new JBossThreadFactory(null, null, null, "test thread %p %t", null, null);

final Thread thread = threadFactory.newThread(new Worker(task));
if (thread == null) {
    throw new ThreadCreationException();
}

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如果您正在使用依赖项注入，则可以创建一个模拟ThreadFactory：

private class NullThreadFactory implements ThreadFactory {
    public Thread newThread(Runnable r) {
        return null;
    }
}

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对于特定的单元测试，使用NullThreadFactory而不是JBossThreadFactory。

+1:或者在创建线程计数后失败的测试。