@Override
	public boolean performOk() {
		super.performOk();

		//@formatter:off
		GhidraProjectCreatorPreferences.setGhidraInstallDirs(
			Arrays.stream(table.getItems())
			.map(item -> new File(item.getText()))
			.collect(Collectors.toSet())
		);

		GhidraProjectCreatorPreferences.setDefaultGhidraInstallDir(
			Arrays.stream(table.getItems())
			.filter(TableItem::getChecked)
			.findFirst()
			.map(item -> new File(item.getText()))
			.orElse(null)
		);
		//@formatter:on

		return true;
	}
Page for Ghidra project creator preferences.
GhidraBuild/EclipsePlugins/GhidraDev/GhidraDevPlugin/src/main/java/ghidradev/ghidraprojectcreator/preferences/GhidraProjectCreatorPreferencePage.java