Interface Traverser<A,R>

@Experimental
@Pro
public interface Traverser<A,R>

An API for QueryPart.$traverse(Traverser) query part traversals.

This API is EXPERIMENTAL. Use at your own risk.

Similar to a Collector for Stream.collect(Collector), this type wraps:

• supplier()
• abort()
• recurse()
• before()
• after()
• finisher()

Method Summary

Modifier and Type	Method	Description
Predicate<A>	abort()	An optional traversal abort condition to short circuit traversal e.g.
BiFunction<A, QueryPart, A>	after()	A callback that is invoked after recursing into a subtree.
BiFunction<A, QueryPart, A>	before()	A callback that is invoked before recursing into a subtree.
Function<A,R>	finisher()	An optional transformation function to turn the temporary data structure supplied by supplier() into the final data structure.
static <A,R> Traverser<A,R>	of(Supplier<A> supplier, Predicate<? super A> abort, Predicate<? super QueryPart> recurse, BiFunction<? super A, ? super QueryPart, ? extends A> before, BiFunction<? super A, ? super QueryPart, ? extends A> after, Function<? super A, ? extends R> finisher)	Convenience method to create a Traverser with a supplier(), abort(), recurse(), before(), after(), and finisher().
static <A,R> Traverser<A,R>	of(Supplier<A> supplier, Predicate<? super A> abort, Predicate<? super QueryPart> recurse, Predicate<? super QueryPart> recurseChildren, BiFunction<? super A, ? super QueryPart, ? extends A> before, BiFunction<? super A, ? super QueryPart, ? extends A> after, Function<? super A, ? extends R> finisher)	Convenience method to create a Traverser with a supplier(), abort(), recurse(), recurseChildren(), before(), after(), and finisher().
static <R> Traverser<R,R>	of(Supplier<R> supplier, BiFunction<? super R, ? super QueryPart, ? extends R> before)	Convenience method to create a Traverser with a supplier() and before().
static <R> Traverser<R,R>	of(Supplier<R> supplier, BiFunction<? super R, ? super QueryPart, ? extends R> before, BiFunction<? super R, ? super QueryPart, ? extends R> after)	Convenience method to create a Traverser with a supplier(), before(), and after().
static <R> Traverser<R,R>	of(Supplier<R> supplier, Predicate<? super R> abort, Predicate<? super QueryPart> recurse, BiFunction<? super R, ? super QueryPart, ? extends R> before)	Convenience method to create a Traverser with a supplier(), abort(), recurse(), and before().
static <R> Traverser<R,R>	of(Supplier<R> supplier, Predicate<? super R> abort, Predicate<? super QueryPart> recurse, BiFunction<? super R, ? super QueryPart, ? extends R> before, BiFunction<? super R, ? super QueryPart, ? extends R> after)	Convenience method to create a Traverser with a supplier(), abort(), recurse(), before(), and after()
Predicate<QueryPart>	recurse()	An optional recursion condition to prevent entering a specific QueryPart, e.g.
Predicate<QueryPart>	recurseChildren()	An optional recursion condition to prevent entering a specific QueryPart's children, e.g.
Supplier<A>	supplier()	A supplier for a temporary data structure to accumulate QueryPart objects into during traversal.

Method Details

of

static <R> Traverser<R,R> of(Supplier<R> supplier,
 BiFunction<? super R, ? super QueryPart, ? extends R> before)

Convenience method to create a Traverser with a supplier() and before().

of

static <R> Traverser<R,R> of(Supplier<R> supplier,
 BiFunction<? super R, ? super QueryPart, ? extends R> before,
 BiFunction<? super R, ? super QueryPart, ? extends R> after)

Convenience method to create a Traverser with a supplier(), before(), and after().

of

static <R> Traverser<R,R> of(Supplier<R> supplier,
 Predicate<? super R> abort,
 Predicate<? super QueryPart> recurse,
 BiFunction<? super R, ? super QueryPart, ? extends R> before)

Convenience method to create a Traverser with a supplier(), abort(), recurse(), and before().

of

static <R> Traverser<R,R> of(Supplier<R> supplier,
 Predicate<? super R> abort,
 Predicate<? super QueryPart> recurse,
 BiFunction<? super R, ? super QueryPart, ? extends R> before,
 BiFunction<? super R, ? super QueryPart, ? extends R> after)

Convenience method to create a Traverser with a supplier(), abort(), recurse(), before(), and after()

of

static <A,R> Traverser<A,R> of(Supplier<A> supplier,
 Predicate<? super A> abort,
 Predicate<? super QueryPart> recurse,
 BiFunction<? super A, ? super QueryPart, ? extends A> before,
 BiFunction<? super A, ? super QueryPart, ? extends A> after,
 Function<? super A, ? extends R> finisher)

Convenience method to create a Traverser with a supplier(), abort(), recurse(), before(), after(), and finisher().

of

static <A,R> Traverser<A,R> of(Supplier<A> supplier,
 Predicate<? super A> abort,
 Predicate<? super QueryPart> recurse,
 Predicate<? super QueryPart> recurseChildren,
 BiFunction<? super A, ? super QueryPart, ? extends A> before,
 BiFunction<? super A, ? super QueryPart, ? extends A> after,
 Function<? super A, ? extends R> finisher)

Convenience method to create a Traverser with a supplier(), abort(), recurse(), recurseChildren(), before(), after(), and finisher().

supplier

Supplier<A> supplier()

A supplier for a temporary data structure to accumulate QueryPart objects into during traversal.

abort

Predicate<A> abort()

An optional traversal abort condition to short circuit traversal e.g. when the searched object has been found.

recurse

Predicate<QueryPart> recurse()

An optional recursion condition to prevent entering a specific QueryPart, e.g. when it is undesired to enter any subqueries.

recurseChildren

Predicate<QueryPart> recurseChildren()

An optional recursion condition to prevent entering a specific QueryPart's children, e.g. when it is desired to traverse only into certain operators.

before

BiFunction<A, QueryPart, A> before()

A callback that is invoked before recursing into a subtree.

after

BiFunction<A, QueryPart, A> after()

A callback that is invoked after recursing into a subtree.

finisher

Function<A,R> finisher()

An optional transformation function to turn the temporary data structure supplied by supplier() into the final data structure.