db4o |

# Db4oCollections.NewIdentityHashMap Method

creates a new database-aware IdentityHashMap.

Db4oMap NewIdentityHashMap(
int initialSize
);

#### Parameters

initialSize
  the initial size of the HashMap

#### Return Value

com.db4o.types.Db4oMap

#### Remarks

creates a new database-aware IdentityHashMap.
Only first class objects already stored to the ObjectContainer (Objects with a db4o ID) can be used as keys for this type of Map. The internal db4o ID will be used as the hash value.
Usage:
- declare a

    java.util.Map

variable in your persistent class.
- fill the variable with this method.
Example:

                class MyClass{
                Map myMap;
                }
                MyClass myObject = new MyClass();
                myObject.myMap = objectContainer.ext().collections().newIdentityMap(0);

#### See Also

Db4oCollections Interface | com.db4o.types Namespace | com.db4o.types.Db4oMap