private DomainObjectListener createDomainObjectListener() {
		// @formatter:off
		return new DomainObjectListenerBuilder(this)
			.ignoreWhen(() -> !isVisible() || isEmpty())
			.any(RESTORED).terminate(() -> setStale(true))
			.any(MEMORY_BLOCK_MOVED, MEMORY_BLOCK_REMOVED, SYMBOL_ADDED, SYMBOL_REMOVED,
				 REFERENCE_ADDED, REFERENCE_REMOVED, REFERENCE_TYPE_CHANGED)
				.call(() -> setStale(true))
			.with(ProgramChangeRecord.class)
				.each(SYMBOL_RENAMED).call(r -> handleSymbolRenamed(r))
			.build();
		// @formatter:on
	}
A variable used to restrict open-ended operations, like expanding all nodes or filtering.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/calltree/CallTreeProvider.java