Hello, I need to know if it's possible to add childs after the parent
is save in the datastore
See the code after : Parent class, Child class and code to create a
new Parent and Child.
/* Parent entity */
@PersistenceCapable(identityType = IdentityType.APPLICATION,
detachable = "true")
public class Parent{
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key idParent;
@Persistent
private String Name;
@Persistent(mappedBy = "p")
private List<Child> children= new ArrayList<Child>();
public Parent(String Name) { this.Name=Name; }
//getters and setters
public Key getIdParent() { return idParent; }
public String getName() { return Name; }
public void setName(String Name) { this.Name= Name; }
public List<Child> getChild() { return children; }
public void setChild(List<Child> children) { this.children=
children; }
public void addChild(Child c){
ArrayList<Child> k = new ArrayList<Child>(children);
k.add(c);
setChild(k);
}
/*Child entity*/
@PersistenceCapable(identityType = IdentityType.APPLICATION,
detachable = "true")
public class Child{
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key idChild;
@Persistent
private int Num;
@Persistent
private Parent p;
public Child(int Num) {this.Num = Num;}
//getters and setters
public Key getIdChild() { return idChild; }
public void setIdChild(Key idChild) { this.idChild= idChild; }
public int getNum() { return Num; }
public void setNum(int Num) { this.Num = Num; }
public Parent getParent() { return p; }
public void setParent(Parent p){ this.p = p; }
/*code to create one parent and add a child to it*/
//new parent
Parent p = new Parent("parent");
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
pm.makePersistent(p);
} finally {
pm.close();
}
//new child
Child c = new Child(1);
c.setParent(p);
p.addChild(c);
pm = PMF.get().getPersistenceManager();
try {
pm.makePersistent(c);
} finally {
pm.close();
}
This code gives an error of the server but the parent is saved in the
datastore.
Thank's for reading and sorry for my english.
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