Here is a sample (code below too):

https://gist.github.com/ryanjaeb/841bb08c0c5fa1bea946

import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.collections.transformation.FilteredList;

public class FilteredListWithoutPredicate {
    public static void main(String[] args) {
        ObservableList<String> source = FXCollections.observableArrayList();
        source.addAll("one", "two", "three");
        System.out.println("source size: " + source.size());

        System.out.println("without predicate: "
                + new FilteredList<>(source).size());

        System.out.println("with predicate: "
                + new FilteredList<>(source, t -> true).size());
    }
}

Steps to reproduce:

1. Run the example.
2. Observe the output.

The output will be:

source size: 3
without predicate: 0
with predicate: 3

This contradicts the JavaDoc for the one arg constructor of FilteredList.

The default value for the predicate property in FilteredList is the ALWAYS_TRUE predicate. The one arg constructor passes ALWAYS_TRUE as the predicate, but, since it's already ALWAYS_TRUE, the predicate property won't be invalidated.

Passing a different instance of an always true predicate is a really simple workaround.