I have an object CategoryBean where are defined a list of other objects CategoryBean (its children) and another object CategoryBean (its parent).
Cloning its children is not a problem, but cloning its parent isn't working. Indeed, when I have my object A and its parent P, when I go through P and get the list of its children (where I should fine A), A has not the same reference than the child of P. The objects equal ("attributly" speaking) but are not the same.
Here is my class and its attributes :
public class CategoryBean implements Externalizable, Cloneable {
public static final boolean ACTIVE = true;
public static final boolean INACTIVE = false;
public static final int VALIDATED = 1;
public static final int NON_OBSERVED = 2;
public static final int IN_PROGRESS = 3;
public static final int PARTIEL = 4;
private String perimetre;
private CategoryBean parentCategory;
private List<CategoryBean> categoryList = new LinkedList<CategoryBean>();
protected String title;
/**
* Category validée ou non
*/
protected int state = NON_OBSERVED;
/**
* Category active ou inactive
*/
protected boolean activated = ACTIVE;
/**
* @return the parentCategory
*/
public CategoryBean getParentCategory() {
return parentCategory;
}
/**
* @param parentCategory
* the parentCategory to set
*/
public void setParentCategory(CategoryBean parentCategory) {
this.parentCategory = parentCategory;
}
/**
* @return the perimetre
*/
public String getPerimetre() {
return perimetre != null ? perimetre.trim() : null;
}
/**
* @param perimetre
* the perimetre to set
*/
public void setPerimetre(String perimetre) {
this.perimetre = perimetre != null ? perimetre.trim() : null;
}
/**
* @return the category
*/
public List<CategoryBean> getCategoryList() {
return categoryList;
}
/**
* @param category
* the category to set
*/
public void setCategoryList(List<CategoryBean> categoryList) {
this.categoryList = categoryList;
}
/**
* @return the title
*/
public String getTitle() {
return title != null ? title.trim() : null;
}
/**
* @param title
* the title to set
*/
public void setTitle(String title) {
this.title = title != null ? title.trim() : null;
}
/**
* @return the state
*/
public int getState() {
return state;
}
/**
* @param state
* the state to set
*/
public void setState(int state) {
this.state = state;
}
/**
* @return the activated
*/
public boolean isActivated() {
return activated;
}
/**
* @param activated
* the activated to set
*/
public void setActivated(boolean activated) {
this.activated = activated;
}
@Override
public int hashCode() {
if (parentCategory != null && categoryList != null && title != null) {
return parentCategory.hashCode() + categoryList.hashCode() + title.hashCode();
} else if (categoryList != null && title != null) {
return parentCategory.hashCode() + categoryList.hashCode() + title.hashCode();
} else {
return super.hashCode();
}
}
@Override
public boolean equals(Object o) {
if (o != null && o instanceof CategoryBean) {
CategoryBean o2 = (CategoryBean) o;
if (getPerimetre() != null && getTitle() != null && getParentCategory() != null) {
return getPerimetre().equals(o2.getPerimetre()) && getTitle().equals(o2.getTitle())
&& getParentCategory().equals(o2.getParentCategory());
} else if (getPerimetre() != null && getTitle() != null && getPerimetre().equals(getTitle())) {
return getPerimetre().equals(o2.getPerimetre()) && getTitle().equals(o2.getTitle());
}
}
return super.equals(o);
}
@SuppressWarnings("unchecked")
@Override
public void readExternal(ObjectInput input) throws IOException, ClassNotFoundException {
setPerimetre((String) input.readObject());
setParentCategory((CategoryBean) input.readObject());
setCategoryList((List<CategoryBean>) input.readObject());
setTitle((String) input.readObject());
setState((Integer) input.readObject());
setActivated((Boolean) input.readObject());
}
@Override
public void writeExternal(ObjectOutput output) throws IOException {
output.writeObject(getPerimetre());
output.writeObject(getParentCategory());
output.writeObject(getCategoryList());
output.writeObject(getTitle());
output.writeObject(getState());
output.writeObject(isActivated());
}
@Override
public CategoryBean clone() throws CloneNotSupportedException {
try {
CategoryBean clone = (CategoryBean) super.clone();
clone.setPerimetre(getPerimetre());
clone.setParentCategory(getParentCategory());
List<CategoryBean> categoryListClone = null;
if (getCategoryList() != null) {
categoryListClone = new LinkedList<CategoryBean>();
for (int i = 0; i < getCategoryList().size(); i++) {
categoryListClone.add(getCategoryList().get(i).clone());
}
}
clone.setCategoryList(categoryListClone);
clone.setTitle(getTitle());
clone.setState(getState());
clone.setActivated(isActivated());
return clone;
} catch (CloneNotSupportedException e) {
throw new InternalError();
}
}
}
Do you know what I do wrong in the clone method ?
Thanks for you help :)
(Edit) Solution :
public CategoryBean clone() throws CloneNotSupportedException {
try {
CategoryBean clone = (CategoryBean) super.clone();
clone.setPerimetre(getPerimetre());
List<CategoryBean> categoryListClone = null;
if (getCategoryList() != null) {
categoryListClone = new LinkedList<CategoryBean>();
for (int i = 0; i < getCategoryList().size(); i++) {
CategoryBean childClone = getCategoryList().get(i).clone();
childClone.setParentCategory(clone);
categoryListClone.add(childClone);
}
}
clone.setCategoryList(categoryListClone);
clone.setTitle(getTitle());
clone.setState(getState());
clone.setActivated(isActivated());
return clone;
} catch (CloneNotSupportedException e) {
throw new InternalError();
}
}
I think you need to cache the parent beans already cloned during the clone operation, so that when clone.setParentCategory is called in the child, this is the cloned parent that is injected in the property...
Not sure it's crystal clear :)... so... something like this (careful, no tested !) :
@Override
public CategoryBean clone() throws CloneNotSupportedException {
return cloneRecursive(new HashMap<CategoryBean, CategoryBean>());
}
private CategoryBean cloneRecursive(Map<CategoryBean, CategoryBean> categoryBeans) throws CloneNotSupportedException {
try {
CategoryBean clone = (CategoryBean) super.clone();
categoryBeans.put(this, clone);
clone.setPerimetre(getPerimetre());
clone.setParentCategory(categoryBeans.get(getParentCategory()));
List<CategoryBean> categoryListClone = null;
if (getCategoryList() != null) {
categoryListClone = new LinkedList<CategoryBean>();
for (int i = 0; i < getCategoryList().size(); i++) {
categoryListClone.add(getCategoryList().get(i).cloneRecursive(categoryBeans));
}
}
clone.setCategoryList(categoryListClone);
clone.setTitle(getTitle());
clone.setState(getState());
clone.setActivated(isActivated());
return clone;
} catch (CloneNotSupportedException e) {
throw new InternalError();
}
}