### Question:
BnButton extends OperationPMButton implements ModelSubscriber { public Path getPath() { return link.getPath(); } BnButton();  BnButton(IOperationPM pModel);  BnButton(ModelProvider provider, Path path);  BnButton(ModelProvider provider); IModelProvider getModelProvider(); void setModelProvider(IModelProvider provider); Path getPath(); void setPath(Path path);  }### Answer:
@Test public void testGetPath() { Path path = new Path("this.op"); this.button.setPath(path); assertEquals("button.getPath()", path, this.button.getPath()); }