Objective-C Code

 
- (NSDictionary *)committedSnapshotForObject:(id)object;

Java Code

 
public native com.apple.yellow.foundation.NSDictionary committedSnapshotForObject (com.apple.yellow.eocontrol.EOEnterpriseObject);

You can next get all the changes to the object's original snapshot.

Objective-C

 
- (NSDictionary *)changesFromSnapshot:(NSDictionary *)snapshot;

Java Code

 
public native com.apple.yellow.foundation.NSDictionary changesFromSnapshot (com.apple.yellow.foundation.NSDictionary);

The NSDictionary object returned from the changesFromSnapshot method (in both languages) only contains the attribute names and their values that refer to uncommitted changes in the object. If there is a to-many attribute, the uncommitted value is an array of two arrays: uncommitted additions and uncommitted deletions.

The following Java sample code gets the NSDictionaries reflecting the prior committed state of an object and its currently changed attributes, based on the API described above:

Java Code

 
/* Assuming that myCustomObject descends from EOCustomObject and already exists */ 
EOEditingContext ec = myCustomObject.editingContext(); 
// The committedSnapshotForObject method expects to have 
// an EOEnterpriseObject as argument, so typecasting is necessary here. 
NSDictionary  originalSnapshot = ec.committedSnapshotForObject((EOEnterpriseObject)myCustomObject); 
NSDictionary changesDict = myCustomObject.changesFromSnapshot(originalSnapshot);

To view all changes recorded in the changed snapshot, you could use the following sample code:

Java Code

 
int count; 
count = changesDict.count(); 
NSArray allKeys = changesDict.allKeys(); 
java.util.Enumerator anEnum = changesDict.keyEnumerator(); 
while (anEnum.hasMoreElements()) { 
    String key = anEnum.nextElement(); 
    String value = changesDict.valueForKey(key); 
    System.out.println("Changes: Key " 
	 + key + "Value " 
	+ value); 
}