JsonPathAst.java

package json.java21.jsonpath;

import java.util.List;
import java.util.Objects;

record JsonPathAst(List<Step> steps) {
    JsonPathAst {
        Objects.requireNonNull(steps, "steps must not be null");
        steps.forEach(s -> Objects.requireNonNull(s, "step must not be null"));
    }

    sealed interface Step permits
            Step.Child,
            Step.Wildcard,
            Step.RecursiveDescent,
            Step.ArrayIndex,
            Step.ArraySlice,
            Step.Union,
            Step.Filter,
            Step.ScriptIndex {

        record Child(String name) implements Step {
            public Child {
                Objects.requireNonNull(name, "name must not be null");
            }
        }

        record Wildcard() implements Step {}

        record RecursiveDescent(RecursiveSelector selector) implements Step {
            public RecursiveDescent {
                Objects.requireNonNull(selector, "selector must not be null");
            }
        }

        sealed interface RecursiveSelector permits RecursiveSelector.Name, RecursiveSelector.Wildcard {
            record Name(String name) implements RecursiveSelector {
                public Name {
                    Objects.requireNonNull(name, "name must not be null");
                }
            }

            record Wildcard() implements RecursiveSelector {}
        }

        record ArrayIndex(int index) implements Step {}

        record ArraySlice(Integer startInclusive, Integer endExclusive) implements Step {}

        record Union(List<Selector> selectors) implements Step {
            public Union {
                Objects.requireNonNull(selectors, "selectors must not be null");
                selectors.forEach(s -> Objects.requireNonNull(s, "selector must not be null"));
            }
        }

        sealed interface Selector permits Selector.Name, Selector.Index {
            record Name(String name) implements Selector {
                public Name {
                    Objects.requireNonNull(name, "name must not be null");
                }
            }

            record Index(int index) implements Selector {}
        }

        record Filter(BoolExpr predicate) implements Step {
            public Filter {
                Objects.requireNonNull(predicate, "predicate must not be null");
            }
        }

        record ScriptIndex(ValueExpr expr) implements Step {
            public ScriptIndex {
                Objects.requireNonNull(expr, "expr must not be null");
            }
        }
    }
}