### Question:
ClientSettingsWrapper { public final void setFillLevelDiagram(TankSelector tank, boolean enabled) { String tankString = tank.name(); String enabledString = String.valueOf(enabled); properties.setProperty("fillLevelDiagram_" + tankString, enabledString); } ClientSettingsWrapper(File settingsFile); final void setServerHostname(TankSelector tank, String hostname); final void setServerPort(TankSelector tank, int portServer); final void setFetchInterval(int intervalMs); final void setOverflowAlarm(TankSelector tank, boolean enabled); final void setUnderflowAlarm(TankSelector tank, boolean enabled); final void setOverheatingAlarm(TankSelector tank, boolean enabled); final void setUndercoolingAlarm(TankSelector tank, boolean enabled); final void setTempDiagram(TankSelector tank, boolean enabled); final void setFillLevelDiagram(TankSelector tank, boolean enabled); final int getFetchInterval(int defaultValue); final boolean getOverheatingAlarm(TankSelector tank, boolean defaultValue); final boolean getUndercoolingAlarm(TankSelector tank, boolean defaultValue); final boolean getOverflowAlarm(TankSelector tank, boolean defaultValue); final boolean getUnderflowAlarm(TankSelector tank, boolean defaultValue); final boolean getTempDiagram(TankSelector tank, boolean defaultValue); final boolean getFillLevelDiagram(TankSelector tank, boolean defaultValue); final String getHostname(TankSelector tank, String defaultValue); final int getPort(TankSelector tank, int defaultValue); final void saveSettings();  }### Answer:
@Test public void testSetFillLevelDiagram() { wrapper.setFillLevelDiagram(testTank, true); assertTrue(wrapper.getFillLevelDiagram(testTank, false)); }