Consider 2 loops with Integer::<init> & Integer::valueOf:
@Benchmark
public void testIntegerValueOf(Blackhole bh) {
    int sum = 0;
    for (int idx = 0; idx < data.length; idx++) {
        sum += Integer.valueOf(data[idx]).intValue();
    }
    bh.consume(sum);
}

@Benchmark
public void testIntegerNew(Blackhole bh) {
    int sum = 0;
    for (int idx = 0; idx < data.length; idx++) {
        sum += new Integer(data[idx]).intValue();
    }
    bh.consume(sum);
}

$ java -jar bench_autobox.jar -jvmArgs '-XX:+UnlockExperimentalVMOptions -XX:+AggressiveUnboxing' '.*'

IteratorBench.testIntegerNew          3.130 �� 0.053  us/op
IteratorBench.testIntegerValueOf  12.546 �� 0.247  us/op

The problem is that VM doesn't unroll loop in testIntegerValueOf because it's not detected as counted.