io.inversion.json.JSFind Maven / Gradle / Ivy
package io.inversion.json;
import io.inversion.utils.Utils;
import java.util.*;
import java.util.stream.Stream;
public interface JSFind {
JSNode getJson();
/**
* A heroically permissive finder supporting JSON Pointer, JSONPath and
* a simple 'dot and wildcard' type of system like so:
* 'propName.childPropName.*.skippedGenerationPropsName.4.fifthArrayNodeChildPropsName.**.recursivelyFoundPropsName'.
*
*
* All forms are internally converted into a 'master' form before processing. This master
* simply uses '.' to separate property names and array indexes and uses uses '*' to represent
* a single level wildcard and '**' to represent a recursive wildcard. For example:
*
* - 'myProp' finds 'myProp' in this node.
*
- 'myProp.childProp' finds 'childProp' on 'myProp'
*
- 'myArrayProp.2.*' finds all properties of the third element of the 'myArrayProp'
*
- '*.myProp' finds 'myProp' in any of the children of this node.
*
- '**.myProp' finds 'myProp' anywhere in my descendents.
*
- '**.myProp.*.value' finds 'value' as a grandchild anywhere under me.
*
- '**.*' returns every element of the document.
*
- '**.5' gets the 6th element of every array.
*
- '**.book[?(@.isbn)]' finds all books with an isbn
*
- '**.[?(@.author = 'Herman Melville')]' finds all book with author 'Herman Melville'
*
*
* Arrays indexes are treated just like property names but with integer names.
* For example "myObject.4.nextProperty" finds "nextProperty" on the 5th element
* in the "myObject" array.
*
*
* JSON Pointer is the least expressive supported form and uses '/' characters to separate properties.
* To support JSON Pointer, we simply replace all '/' characters for "." characters before
* processing.
*
*
* JSON Path is more like XML XPath but uses '.' instead of '/' to separate properties.
* Technically JSON Path statements are supposed to start with '$.' but that is optional here.
* The best part about JSON Path is the query filters that let you conditionally select
* elements.
*
* Below is the implementation status of various JSON Path features:
*
* - SUPPORTED $.store.book[*].author //the authors of all books in the store
*
- SUPPORTED $..author //all authors
*
- SUPPORTED $.store..price //the prices of all books
*
- SUPPORTED $..book[2] //the third book
*
- SUPPORTED $..book[?(@.price@lt;10)] //all books priced @lt; 10
*
- SUPPORTED $..[?(@.price@lt;10)] //find any node with a price property
*
- SUPPORTED $..[?(@.*.price@lt;10)] //find the parent of any node with a price property
*
- SUPPORTED $..book[?(@.author = 'Herman Melville')] //all books where 'Herman Melville' is the author
*
- SUPPORTED $..* //all members of JSON structure.
*
- SUPPORTED $..book[(@.length-1)] //the last book in order
*
- SUPPORTED $..book[-1:] //the last book in order
*
- SUPPORTED $..book[0,1] //the first two books
*
- SUPPORTED $..book[:2] //the first two books
*
- SUPPORTED $..book[?(@.isbn)] //find all books with an isbn property
*
- SUPPORTED $..[?(@.isbn)] //find any node with an isbn property
*
- SUPPORTED $..[?(@.*.isbn)] //find the parent of any node with an isbn property
*
- SUPPORTED $..[?(@.*.*.isbn)] //find the grandparent of any node with an isbn property
*
*
*
*
* The JSON Path following boolean comparison operators are supported:
*
* - =
*
- @gt;
*
- @lt;
*
- @gt;=
*
- @lt;=
*
- !=
*
*
*
* JsonPath bracket-notation such as "$['store']['book'][0]['title']"
* is currently not supported.
*
* @param qty the maximum number of results
* @param pathExpressions defines the properties to find
* @return an array of found values
* @see JSON Pointer
* @see JSON Path
* @see JSON Path
*/
default JSList findAll(int qty, String... pathExpressions) {
JSList found = new JSList();
for(int i =0; pathExpressions != null && i> visited) {
JSONPathTokenizer tok = new JSONPathTokenizer(//
"['\"", //openQuoteStr
"]'\"", //closeQuoteStr
"]", //breakIncludedChars
".", //breakExcludedChars
"", //unquotedIgnoredChars
". \t", //leadingIgnoredChars
pathExpression //chars
);
List path = tok.asList();
return findAll0(path, qty, collected, visited);
}
default List findAll0(List path, int qty, List collected, HashMap> visited) {
JSNode json = getJson();
//-- infinite recursion protection
//-- you can visit a path more than once trying different parts of the search path
//-- but you can only visit a node once for any given permutation of the path.
String pathStr = path.toString();
Set old = visited.get(pathStr);
if (old == null) {
old = new HashSet();
visited.put(pathStr, old);
}
if (old.contains(this))
return collected;
old.add(this);
//-- end infinite recursion protection
if (qty > 1 && collected.size() >= qty)
return collected;
String nextSegment = path.get(0);
if ("*".equals(nextSegment)) {
if (path.size() == 1) {
Collection values = json.values();
for (Object value : values) {
if (!collected.contains(value) && (qty < 1 || collected.size() < qty))
collected.add(value);
}
} else {
List nextPath = path.subList(1, path.size());
for (Object value : json.values()) {
if (value instanceof JSNode) {
((JSNode) value).findAll0(nextPath, qty, collected, visited);
}
}
}
} else if ("**".equals(nextSegment)) {
if (path.size() != 1) {
List nextPath = path.subList(1, path.size());
this.findAll0(nextPath, qty, collected, visited);
for (Object value : json.values()) {
if (value instanceof JSNode) {
((JSNode) value).findAll0(path, qty, collected, visited);
}
}
}
}
//else if (this instanceof JSList && nextSegment.startsWith("[") && nextSegment.endsWith("]")){
else if (nextSegment.startsWith("[") && nextSegment.endsWith("]")) {
//this is a JSONPath filter that is not just an array index
String expr = nextSegment.substring(1, nextSegment.length() - 1).trim();
if (expr.startsWith("?(") && expr.endsWith(")")) {
JSONPathTokenizer tokenizer = new JSONPathTokenizer(//
"'\"", //openQuoteStr
"'\"", //closeQuoteStr
"?=<>!", //breakIncludedChars...breakAfter
"]=<>! ", //breakExcludedChars...breakBefore
"[()", //unquotedIgnoredChars
"]. \t", //leadingIgnoredChars
expr);
String token;
String func = null;
String subpath = null;
String op = null;
String value = null;
//-- Choices after tokenization
//-- $..book[2] -> 2
//-- $..book[author] -> author
//-- $..book[(@.length-1)] -> @_length-1
//-- $..book[-1:] -> -1:
//-- $..book[0,1] -> 0,1
//-- $..book[:2] -> :2
//-- $..book[?(@.isbn)] -> ? @_isbn
//-- $..book[?(@.price<10)] -> ?
while ((token = tokenizer.next()) != null) {
if (token.equals("?")) {
func = "?";
continue;
}
if (token.startsWith("@_")) {
subpath = token.substring(2);
} else if (Utils.in(token, "=", ">", "<", "!")) {
if (op == null)
op = token;
else
op += token;
} else if (subpath != null && op != null && value == null) {
value = token;
if (json.isList()) {
for (Object child : json.values()) {
if (child instanceof JSNode) {
List found = ((JSNode) child).findAll0(subpath, -1, new ArrayList(), visited);
for (Object val : found) {
if (eval(val, op, value)) {
if (!collected.contains(child) && (qty < 1 || collected.size() < qty))
collected.add(child);
}
}
}
}
} else {
List found = findAll0(subpath, -1, new ArrayList(), visited);
for (Object val : found) {
if (eval(val, op, value)) {
if (!collected.contains(this) && (qty < 1 || collected.size() < qty)) {
collected.add(this);
break;
}
}
}
}
func = null;
subpath = null;
op = null;
value = null;
}
}
//$..book[?(@.isbn)] -- checks for the existence of a property
if ("?".equals(func) && subpath != null) {
if (op != null || value != null) {
//unparseable...do nothing
}
if (json.isList()) {
for (Object child : json.values()) {
if (child instanceof JSNode) {
List found = ((JSNode) child).findAll0(subpath, -1, new ArrayList(), visited);
for (Object val : found) {
if (!collected.contains(child) && (qty < 1 || collected.size() < qty))
collected.add(child);
}
}
}
} else {
List found = findAll0(subpath, -1, new ArrayList(), visited);
if (found.size() > 0) {
if (!collected.contains(this) && (qty < 1 || collected.size() < qty))
collected.add(this);
}
}
}
} else {
//-- $..book[(@.length-1)] -> @_length-1
//-- $..book[-1:] -> -1:
//-- $..book[0,1] -> 0,1
//-- $..book[:2] -> :2
if (json.isList()) {
int length = ((JSList) this).size();
List found = new ArrayList();
if (expr.startsWith("(@_length-")) {
int index = Integer.parseInt(expr.substring(expr.indexOf("-") + 1, expr.length() - 1).trim());
if (length - index > 0) {
found.add(json.get(length - index));
}
} else if (expr.startsWith(":")) {
int count = Integer.parseInt(expr.substring(1).trim());
for (int i = 0; i < length && i < count; i++) {
found.add(json.get(count));
}
} else if (expr.endsWith(":")) {
int idx = Integer.parseInt(expr.substring(0, expr.length() - 1).trim()) * -1;
if (idx <= length)
found.add(json.get(length - idx));
} else {
try {
int start = Integer.parseInt(expr.substring(0, expr.indexOf(":")).trim());
int end = Integer.parseInt(expr.substring(expr.indexOf(":") + 1).trim());
for (int i = start; i <= end && i < length; i++) {
found.add(json.get(i));
}
} catch (Exception ex) {
System.out.println(expr);
ex.printStackTrace();
}
}
if (found.size() > 0) {
if (path.size() > 1) {
//TODO: this is a dead assignment...need a test case here
List nextPath = path.subList(1, path.size());
} else {
collected.addAll(found);
}
}
}
}
} else {
Object found = json.get(nextSegment);
if (found != null) {
if (path.size() == 1) {
if (!collected.contains(found) && (qty < 1 || collected.size() < qty))
collected.add(found);
} else if (found instanceof JSNode) {
((JSNode) found).findAll0(path.subList(1, path.size()), qty, collected, visited);
}
}
}
return collected;
}
/**
* Convenience overloading of {@link #findAll(int, String...)} that returns the first item found
*
* @param pathExpression specifies the properties to find
* @return the first item found at pathExpression
* @see #findAll(int, String...)
*/
default Object find(String pathExpression) {
JSList found = findAll(1, pathExpression);
if (found.size() > 0)
return found.get(0);
return null;
}
/**
* Convenience overloading of {@link #find(String)}
*
* @param pathExpression specifies the nodes to find
* @return the first value found at pathExpression cast as a JSMap if exists else null
* @throws ClassCastException if the object found is not a JSNode
* @see #find(String)
*/
default JSMap findMap(String pathExpression) {
return (JSMap) find(pathExpression);
}
/**
* Convenience overloading of {@link #find(String)}
*
* @param pathExpression specifies the nodes to find
* @return the first value found at pathExpression cast as a JSNode if exists else null
* @throws ClassCastException if the object found is not a JSNode
* @see #find(String)
*/
default JSNode findNode(String pathExpression) {
return (JSNode) find(pathExpression);
}
/**
* Convenience overloading of {@link #find(String)}
*
* @param pathExpression specifies the properties to find
* @return the first value found at pathExpression cast as a JSList if exists else null
* @throws ClassCastException if the object found is not a JSList
* @see #find(String)
*/
default JSList findList(String pathExpression) {
return (JSList) find(pathExpression);
}
/**
* Convenience overloading of {@link #find(String)}
*
* @param pathExpression specifies the properties to find
* @return the first value found at pathExpression stringified if exists else null
* @see #find(String)
*/
default String findString(String pathExpression) {
Object found = find(pathExpression);
if (found != null)
return found.toString();
return null;
}
/**
* Convenience overloading of {@link #find(String)}
*
* @param pathExpression specifies the properties to find
* @return the first value found at pathExpression stringified and parsed as an int if exists else -1
* @see #find(String)
*/
default int findInt(String pathExpression) {
Object found = find(pathExpression);
if (found != null)
return Utils.atoi(found);
return -1;
}
/**
* Convenience overloading of {@link #find(String)}
*
* @param pathExpression specifies the properties to find
* @return the first value found at pathExpression stringified and parsed as a long if exists else -1
* @see #find(String)
*/
default long findLong(String pathExpression) {
Object found = find(pathExpression);
if (found != null)
return Utils.atol(found);
return -1;
}
/**
* Convenience overloading of {@link #find(String)}
*
* @param pathExpression specifies the properties to find
* @return the first value found at pathExpression stringified and parsed as a double if exists else -1
* @see #find(String)
*/
default double findDouble(String pathExpression) {
Object found = find(pathExpression);
if (found != null)
return Utils.atod(found);
return -1;
}
/**
* Convenience overloading of {@link #find(String)}
*
* @param pathExpression specifies the properties to find
* @return the first value found at pathExpression stringified and parsed as a boolean if exists else false
* @see #find(String)
*/
default boolean findBoolean(String pathExpression) {
Object found = find(pathExpression);
if (found != null)
return Utils.atob(found);
return false;
}
/**
* Convenience overloading of {@link #findAll(int, String...)}
*
* @param pathExpressions specifies the properties to find
* @return all items found for pathExpression
* @see #findAll(int, String...)
*/
default JSList findAll(String... pathExpressions) {
return findAll(-1, pathExpressions);
}
/**
* Convenience overloading of {@link #findAll(int, String...)}
*
* @param pathExpressions specifies the properties to find
* @return all items found for pathExpression cast as a List
* @see #findAll(int, String...)
*/
default List findMaps(String... pathExpressions) {
return (List)findAll(pathExpressions);
}
default List findLists(String... pathExpressions) {
return (List)findAll(pathExpressions);
}
default Stream streamAll() {
List all = findAll("**.*").asList();
all.add(this);
return all.stream();
}
static boolean eval(Object var, String op, Object value) {
value = Utils.dequote(value.toString());
if (var instanceof Number) {
try {
value = Double.parseDouble(value.toString());
} catch (Exception ex) {
//ok, value was not a number...ignore
}
}
if (var instanceof Boolean) {
try {
value = Boolean.parseBoolean(value.toString());
} catch (Exception ex) {
//ok, value was not a boolean...ignore
}
}
int comp = ((Comparable) var).compareTo(value);
switch (op) {
case "=":
return comp == 0;
case ">":
return comp > 0;
case ">=":
return comp >= 0;
case "<":
return comp < 0;
case "<=":
return comp <= 0;
case "!=":
return comp != 0;
default:
throw new UnsupportedOperationException("Unknown operator '" + op + "'");
}
}
/**
* Simply replaces "/" with "."
*
* Slashes in property names (seriously a stupid idea anyway) which is supported
* by JSON Pointer is not supported.
*
* @param jsonPointer a slash based path expression
* @return a dot based path expression
*/
static String fromJsonPointer(String jsonPointer) {
if (jsonPointer.charAt(0) == '#') {
jsonPointer = jsonPointer.substring(1);
if (jsonPointer.charAt(0) == '/')
jsonPointer = jsonPointer.substring(1);
}
return jsonPointer.replace('/', '.');
}
/**
* Converts a proper json path statement into its "relaxed dotted wildcard" form
* so that it is easier to parse.
*/
static String fromJsonPath(String jsonPath) {
if (jsonPath.charAt(0) == '#') {
jsonPath = jsonPath.substring(1);
}
if (jsonPath.charAt(0) == '$')
jsonPath = jsonPath.substring(1);
jsonPath = jsonPath.replace("@.", "@_"); //from jsonpath spec..switching to "_" to make parsing easier
jsonPath = jsonPath.replaceAll("([a-zA-Z])\\[", "$1.["); //from json path spec array[index] converted to array.[index]. to support array.index.value legacy format.
jsonPath = jsonPath.replace("..", "**."); //translate from jsonpath format
jsonPath = jsonPath.replaceAll("([a-zA-Z])[*]", "$1.*"); //translate from jsonpath format
jsonPath = jsonPath.replaceAll("([a-zA-Z])\\[([0-9]*)\\]", "$1.$2"); // x[1] to x.1
jsonPath = jsonPath.replaceAll("([a-zA-Z])\\[([0-9]*)\\]", "$1.$2"); // x[1] to x.1
jsonPath = jsonPath.replaceAll("\\.\\[([0-9]*)\\]", ".$1"); //translate .[1]. to .1. */
jsonPath = jsonPath.replaceAll("\\[([0-9]*)\\]", "$1"); // [123] to 123 ...catches a root array
jsonPath = jsonPath.replace("[*]", "*");
//System.out.println(pathStr);
return jsonPath;
}
}