Currently if we create a record it's fields are compared in their declaration order. This might be ineffective in cases when two objects have "heavy" fields equals to each other, but different "lightweight" fields (heavy and lightweight in terms of comparison) e.g. primitives, enums, nullable/non-nulls etc.
If we have declared a record like public record MyRecord(String field1, int field2) {} It's equals() looks like: public final equals(Ljava/lang/Object;)Z L0 LINENUMBER 3 L0 ALOAD 0 ALOAD 1 INVOKEDYNAMIC equals(Lcom/caspianone/openbanking/productservice/controller/MyRecord;Ljava/lang/Object;)Z [ // handle kind 0x6 : INVOKESTATIC java/lang/runtime/ObjectMethods.bootstrap(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/TypeDescriptor;Ljava/lang/Class;Ljava/lang/String;[Ljava/lang/invoke/MethodHandle;)Ljava/lang/Object; // arguments: com.caspianone.openbanking.productservice.controller.MyRecord.class, "field1;field2", // handle kind 0x1 : GETFIELD com/caspianone/openbanking/productservice/controller/MyRecord.field1(Ljava/lang/String;), // handle kind 0x1 : GETFIELD com/caspianone/openbanking/productservice/controller/MyRecord.field2(I) ] IRETURN L1 LOCALVARIABLE this Lcom/caspianone/openbanking/productservice/controller/MyRecord; L0 L1 0 LOCALVARIABLE o Ljava/lang/Object; L0 L1 1 MAXSTACK = 2 MAXLOCALS = 2 This can be improved by rearranging the comparison order of the fields moving enums and primitives upper, and collections/arrays lower. ------------- Commit messages: - 8322292: Update copyright - 8322292: Shift arrays and Iterables down - Improve Record.equals() Changes: https://git.openjdk.org/jdk/pull/17143/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17143&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8322292 Stats: 12 lines in 1 file changed: 9 ins; 0 del; 3 mod Patch: https://git.openjdk.org/jdk/pull/17143.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/17143/head:pull/17143 PR: https://git.openjdk.org/jdk/pull/17143