'ScheduledThreadPoolExecutor' with zero core threads

Reports any java.util.concurrent.ScheduledThreadPoolExecutor instances in which corePoolSize is set to zero via the setCorePoolSize method or the object constructor.

A ScheduledThreadPoolExecutor with zero core threads will run nothing.

Example:

  void foo(int corePoolSize) {
      if (corePoolSize != 0) return;
      ThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(corePoolSize); // warning
      executor.setCorePoolSize(corePoolSize); // warning
  }

Locating this inspection

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

ScheduledThreadPoolExecutorWithZeroCoreThreads

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Settings or Preferences | Editor | Inspections | Java | Probable bugs

Inspection ID: ScheduledThreadPoolExecutorWithZeroCoreThreads

Suppressing Inspection

You can suppress this inspection by placing the following comment marker before the code fragment where you no longer want messages from this inspection to appear:

//noinspection ScheduledThreadPoolExecutorWithZeroCoreThreads

More detailed instructions as well as other ways and options that you have can be found in the product documentation:

IntelliJ IDEA 2025.3

Inspection Details
By default bundled with:	IntelliJ IDEA 2025.3, Qodana for JVM 2025.3,

Last modified: 03 December 2025