javamaxlimitrecordjava-record

How many fields can a Java record hold?

What is the maximum number of properties (“record components”, technically) defined in a Java record?

I read the specification, JEP 395: Records. No mention of a limit.

Solution

  • 255 - 1 = 254

    Due to the limit on method descriptor length, the maximum number of parameters a method can define is 255. Including the this, since a record constructor is non-static, that leaves 254.

    See Java Virtual Machine Specification, 4.3.3. Method Descriptors

    I believe a record must have at least one constructor that takes all properties as individual parameters, so this would effectively limit the number of record components.