Comparing Two Json Objects Irrespective of the Sequence of Elements in Them

How to compare two JSON objects with the same elements in a different order equal?

If you want two objects with the same elements but in a different order to compare equal, then the obvious thing to do is compare sorted copies of them - for instance, for the dictionaries represented by your JSON strings a and b:

import json

a = json.loads("""
{
"errors": [
{"error": "invalid", "field": "email"},
{"error": "required", "field": "name"}
],
"success": false
}
""")

b = json.loads("""
{
"success": false,
"errors": [
{"error": "required", "field": "name"},
{"error": "invalid", "field": "email"}
]
}
""")
>>> sorted(a.items()) == sorted(b.items())
False

... but that doesn't work, because in each case, the "errors" item of the top-level dict is a list with the same elements in a different order, and sorted() doesn't try to sort anything except the "top" level of an iterable.

To fix that, we can define an ordered function which will recursively sort any lists it finds (and convert dictionaries to lists of (key, value) pairs so that they're orderable):

def ordered(obj):
if isinstance(obj, dict):
return sorted((k, ordered(v)) for k, v in obj.items())
if isinstance(obj, list):
return sorted(ordered(x) for x in obj)
else:
return obj

If we apply this function to a and b, the results compare equal:

>>> ordered(a) == ordered(b)
True

Testing two JSON objects for equality ignoring child order in Java [closed]

As a general architectural point, I usually advise against letting dependencies on a particular serialization format bleed out beyond your storage/networking layer; thus, I'd first recommend that you consider testing equality between your own application objects rather than their JSON manifestations.

Having said that, I'm currently a big fan of Jackson which my quick read of their ObjectNode.equals() implementation suggests does the set membership comparison that you want:

public boolean equals(Object o)
{
if (o == this) return true;
if (o == null) return false;
if (o.getClass() != getClass()) {
return false;
}
ObjectNode other = (ObjectNode) o;
if (other.size() != size()) {
return false;
}
if (_children != null) {
for (Map.Entry<String, JsonNode> en : _children.entrySet()) {
String key = en.getKey();
JsonNode value = en.getValue();

JsonNode otherValue = other.get(key);

if (otherValue == null || !otherValue.equals(value)) {
return false;
}
}
}
return true;
}

How to compare two JSON strings when the order of entries keep changing

Jackson Json parser has a nice feature that it can parse a Json String into a Map. You can then query the entries or simply ask on equality:

import com.fasterxml.jackson.databind.ObjectMapper;

import java.util.*;

public class Test
{
public static void main(String... args)
{
String input1 = "{\"state\":1,\"cmd\":1}";
String input2 = "{\"cmd\":1,\"state\":1}";
ObjectMapper om = new ObjectMapper();
try {
Map<String, Object> m1 = (Map<String, Object>)(om.readValue(input1, Map.class));
Map<String, Object> m2 = (Map<String, Object>)(om.readValue(input2, Map.class));
System.out.println(m1);
System.out.println(m2);
System.out.println(m1.equals(m2));
} catch (Exception e) {
e.printStackTrace();
}
}
}

The output is

{state=1, cmd=1}
{cmd=1, state=1}
true

Groovy compare two json with unknown nodes names and values

Just compare the slurped maps:

def map1 = new JsonSlurper().parseText(document1)
def map2 = new JsonSlurper().parseText(document2)

assert map1 == map2


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