what are the changes that I need to make if I am using jdk 7 and want to use lambda expression?
I am comparing 2 xml files and want to ignore specific nodes hence using this expression

```
final Diff documentDiff = DiffBuilder
            .compare(expectedSource)
            .withTest(actualSource)
            .withNodeFilter(node -> !node.getNodeName().equals(someName))
            .build();

```

> 
> error: Syntax error on token '-',-- expected
> 
> 
>