奇怪的Java迭代器項目被取代

所以，在我的代碼中，我得到一個組件列表，迭代組件，在每個組件內部獲得組件的維護並遍歷它們。問題是，該項目被beying替換，而不是重新創建，如我所願：奇怪的Java迭代器項目被取代

List<ComponentRelation> componentRelations = getComponentRelations(); 

List<MaintenanceRequired> allMaintenancesRequired = new ArrayList<MaintenanceRequired>(); 

for (Iterator<ComponentRelation> iterator = componentRelations.iterator(); iterator.hasNext();) { 
    ComponentRelation componentRelation = iterator.next(); 
    System.out.println("Getting maintenances from "+componentRelation.getComponent().getName()+" at position "+ComponentInstallationPosition.getPositionString(componentRelation.getInstallationPosition())); 
    for (Iterator<MaintenanceRequired> iterator2 = maintenancesDAO.getRequiredMaintenancesByComponentRelation(componentRelation).iterator(); iterator2.hasNext();) { 
     MaintenanceRequired maintenanceRequired = (MaintenanceRequired) iterator2.next(); 
     maintenanceRequired.setMaintenancePerformedOnComponent(omponentRelation); 
      allMaintenancesRequired.add(maintenanceRequired); 
    } 
}

因此，println的是正確的，但該項目內：

public void setMaintenancePerformedOnComponent(ComponentRelation maintenancePerformedOnComponent) { 
    if (this.maintenancePerformedOnComponent!=null) 
     System.out.println("SETTING "+ComponentInstallationPosition.getPositionString(this.maintenancePerformedOnComponent.getInstallationPosition())+" to "+ComponentInstallationPosition.getPositionString(maintenancePerformedOnComponent.getInstallationPosition())); 
    else System.out.println("SETTING "+ComponentInstallationPosition.getPositionString(maintenancePerformedOnComponent.getInstallationPosition())); 
    this.maintenancePerformedOnComponent = maintenancePerformedOnComponent; 
}

所以印刷說：

"getting maintenances from X-1, position 1" 
"SETTING 1" 
"SETTING 1" 
"SETTING 1" 
"SETTING 1" 
"SETTING 1" 
"getting maintenances from X-2, position 2" 
"SETTING 1 to 2" 
"SETTING 1 to 2" 
"SETTING 1 to 2" 
"SETTING 1 to 2" 
"SETTING 1 to 2"

那麼，爲什麼他會設置1到2，如果它是另一個對象？

正如約翰問，我做什麼吧：

create empty list of items Y; 

get list of items X; 

iterator of list of items X { 
    get from database all Y inside X and iterate{ 
     set iterated Y that he has a position K; 
     put iterated Y inside created initially empty list of Y; // first line 
    } 
}

來源

2014-01-14 Vitor Mendes

靜態類變量？ – turbo

如果你想出一個簡短但完整的例子來證明這個問題，理想情況是這個例子中沒有那麼冗長和明確的商業特定名稱，那麼它會更容易幫助你。 –

不是靜態的..現在增加更簡單的例子 –

採取仔細看看：

System.out.println("SETTING "+ComponentInstallationPosition.getPositionString(this.maintenancePerformedOnComponent.getInstallationPosition())+" to "+ComponentInstallationPosition.getPositionString(maintenancePerformedOnComponent.getInstallationPosition()));

你不要引用當地maintenancePerformedOnComponent但this.maintenancePerformedOnComponent

來源

2014-01-14 17:01:00

是的，正如解釋過的那樣，這是在對象中的設置者。感謝您的回覆，還有其他想法？ –

奇怪的Java迭代器項目被取代

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