Custom child for java file node in project tree

I'm trying to add custom children to java files in project tree. I created implemetion of TreeStructureProvider, but node isn't added to tree.

public class AndroidViewTreeStructureProvider implements TreeStructureProvider {


    @Override
    public Collection<AbstractTreeNode> modify(AbstractTreeNode abstractTreeNode, Collection<AbstractTreeNode> abstractTreeNodes, ViewSettings viewSettings) {

        if (abstractTreeNode.getValue() instanceof PsiJavaDirectoryImpl) {
            for (AbstractTreeNode child : abstractTreeNodes) {

                if (child instanceof JavaSourceNode) {
                    return abstractTreeNodes;
                }

                if(child.getValue() instanceof PsiJavaFileImpl) {
                    PsiJavaFileImpl javaFile = (PsiJavaFileImpl) child.getValue();
                    child.getChildren().add(new JavaSourceNode(javaFile, abstractTreeNode.getProject()));
                }
            }
        }
        return abstractTreeNodes;
    }
    @Nullable
    @Override
    public Object getData(Collection<AbstractTreeNode> abstractTreeNodes, String s) {
        return null;
    }
    private class JavaSourceNode extends ProjectViewNode<String> {
        protected JavaSourceNode(PsiJavaFileImpl src, Project projects) {
            super(projects, src.getName(), ViewSettings.DEFAULT);
        }
        @Override
        public boolean contains(@NotNull VirtualFile virtualFile) {
            return false;  //To change body of implemented methods use File | Settings | File Templates.
        }

        @NotNull
        @Override
        public Collection<? extends AbstractTreeNode> getChildren() {
            Collection<PsiFileNode> children = new ArrayList<PsiFileNode>();
            return children;
        }
        protected void update(PresentationData presentation) {
            presentation.setPresentableText(getValue());
            presentation.setIcon(PlatformIcons.SYMLINK_ICON);
        }
    }
}