### Question:
ActionRetractFactPlugin extends BaseDecisionTableColumnPlugin implements HasAdditionalInfoPage { @Override public void setHeader(final String header) { editingCol().setHeader(header); fireChangeEvent(additionalInfoPage); } @Inject  ActionRetractFactPlugin(final PatternToDeletePage patternToDeletePage,
                                   final AdditionalInfoPage additionalInfoPage,
                                   final Event<WizardPageStatusChangeEvent> changeEvent,
                                   final TranslationService translationService); @Override void init(final NewGuidedDecisionTableColumnWizard wizard); @Override String getTitle(); @Override List<WizardPage> getPages(); @Override Boolean generateColumn(); @Override ActionRetractFactCol52 editingCol(); @Override String getHeader(); @Override void setHeader(final String header); @Override Set<String> getAlreadyUsedColumnHeaders(); @Override boolean isHideColumn(); @Override void setHideColumn(boolean hideColumn); @Override void setInsertLogical(final Boolean value); @Override void setUpdate(final Boolean value); @Override boolean showUpdateEngineWithChanges(); @Override boolean showLogicallyInsert(); @Override boolean isLogicallyInsert(); @Override boolean isUpdateEngine(); String getEditingColStringValue(); void setEditingColStringValue(final String pattern); void setPatternToDeletePageAsCompleted(); Boolean isPatternToDeletePageCompleted(); @Override Type getType();  }### Answer:
@Test public void testSetHeader() throws Exception { final String header = "Header"; doReturn(editingCol).when(plugin).editingCol(); plugin.setHeader(header); verify(editingCol).setHeader(header); verify(plugin).fireChangeEvent(additionalInfoPage); }