[AVRO-2135] ResolvingGrammarGenerator.LitS2 equals method violates contract

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.8.2
• Component/s: java
• Assignee: Unassigned
• Reporter: Ivan Sopov
• Created: 27/Jan/18 12:03
• Updated: 27/Jan/18 12:03

Description

In comments this class is called "Clever trick", however its equals method does violates the equals contract, as demonstrated by this small program:

package org.apache.avro.io.parsing;

import org.apache.avro.Schema;
import org.apache.avro.Schema.Type;
import org.apache.avro.io.parsing.ResolvingGrammarGenerator.LitS2;
import org.apache.avro.io.parsing.ValidatingGrammarGenerator.LitS;

public class LitSTest {
    public static void main(String[] args) {
        Schema schema = Schema.create(Type.BOOLEAN);
        LitS parent = new ValidatingGrammarGenerator.LitS(schema);
        LitS2 child = new ResolvingGrammarGenerator.LitS2(schema,schema);

        System.out.println(parent.equals(child));
        System.out.println(child.equals(parent));
    }
}

Behavior is dependent on internal non-standardized behavior of the HashMap and may broke with update or switch to other java vendor.

Moreover, without LitS2 there is no sense in LitS class if IdentityHashMap is used.