Call to 'Thread.start()' during object construction

Reports calls to start() on java.lang.Thread or any of its subclasses during object construction.

While occasionally useful, such constructs should be avoided due to inheritance issues. Subclasses of a class that launches a thread during the object construction will not have finished any initialization logic of their own before the thread has launched.

This inspection does not report if the class that starts a thread is declared final.

Example:

  class MyThread extends Thread {
    MyThread() {
      start();
    }
  }

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.

CallToThreadStartDuringObjectConstruction

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | Java | Threading issues

Inspection ID: ThreadStartInConstruction

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 CallToThreadStartDuringObjectConstruction

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