GenericTypeIndicator

public abstract class GenericTypeIndicator extends Object

Due to the way that Java implements generics (type-erasure), it is necessary to use a slightly more complicated method to properly resolve types for generic collections at runtime. To solve this problem, Firebase Database accepts subclasses of this class in calls to getValue (getValue(GenericTypeIndicator), getValue(GenericTypeIndicator)) and returns a properly-typed generic collection.

As an example, you might do something like this to get a list of Message instances from a DataSnapshot: 


     class Message {
         private String author;
         private String text;

         private Message() {}

         public Message(String author, String text) {
             this.author = author;
             this.text = text;
         }

         public String getAuthor() {
             return author;
         }

         public String getText() {
             return text;
         }
     }

     // Later ...

     GenericTypeIndicator<List<Message>> t = new GenericTypeIndicator<List<
     Message>>()
 {};
     List<Message> messages = snapshot.getValue(t);

Public Constructor Summary

GenericTypeIndicator()

Inherited Method Summary

Object
clone()
boolean
equals(Object arg0)
void
finalize()
final Class<?>
getClass()
int
hashCode()
final void
notify()
final void
notifyAll()
String
toString()
final void
wait(long arg0, int arg1)
final void
wait(long arg0)
final void
wait()

Public Constructors

public GenericTypeIndicator ()