Is there an expected date for when Java data classes will be introduced?

Question

Scala (case classes) and C# (structs) have support for data classes. When is Java expected to offer support for this language feature?

Answer 1

With a bit of reseach, I ended up with Data Classes and Sealed Types for Java by Brian Goetz.

Here is the JEP, Records (Preview), linking to the above.

Summary - It is just an idea/JEP. So, we cannot tell when it would be implemented (or if it would be implemented at all)

Answer 2

The tentative date is March 2020 for the release of JDK 14.

In Nov. 2019, the JEP 359 about Records (data carriers classes) has been confirmed as being part of Java 14 as a preview (meaning, as commented below by Basil Bourque, it needs to be enabled explicitly and it can be removed in the future).

Still: you can start experimenting with it starting with Java 14, March 2020.

As presented here, record Range(int lo, int hi) would replace

package javax0.geci.tests.record;

import javax0.geci.annotations.Geci;

@Geci("record")
public final class Range {

    final  int  lo;
    final  int  hi;

    //<editor-fold id="record">

    public Range(final int lo, final int hi) {
        this.lo = lo;
        this.hi = hi;
    }

    public int getLo() {
        return lo;
    }

    public int getHi() {
        return hi;
    }

    @Override
    public int hashCode() {
        return java.util.Objects.hash(lo, hi);
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Range that = (Range) o;
        return java.util.Objects.equals(that.lo, lo) && java.util.Objects.equals(that.hi, hi);
    }

    //</editor-fold>
}