How to increase heap memory size for Spock Framework?

Question

The Java program runs fine but the test fails with the message:

Caused by: java.lang.OutOfMemoryError: Java heap space
    at java.base/java.util.BitSet.initWords(BitSet.java:167)
    at java.base/java.util.BitSet.<init>(BitSet.java:162)
    at lv.id.jc.ipv4.IntSet.<init>(IntSet.java:6)
    at lv.id.jc.ipv4.IntSetTest.$spock_initializeFields(IntSetTest.groovy:11)

I already set GROOVY_OPTS to -Xmx1g but it doesn't help.

I use test framework Spock 2.0 and java code under test is

public class IntSet {
    private final BitSet[] storage = {new BitSet(Integer.MAX_VALUE), new BitSet(Integer.MAX_VALUE)};

    public void add(int i) {
        if (i >= 0) {
            storage[0].set(i);
        } else {
            storage[1].set(-++i);
        }
    }

    public long size() {
        return (long) storage[0].cardinality() + storage[1].cardinality();
    }
}

I can't find in Spock Framework documentation how to solve such a problem. I use IntelliJ and gradle.

I will be grateful for any ideas.

Addition information. I set property in gradlew file:

DEFAULT_JVM_OPTS='"-Xmx2048m" "-Xms128m"'

I run the program using this command:

./gradlew run -q --console=plain --args="ip_addresses"

It works fine and prints the correct result. However, when I run the test with command:

./gradlew test

then I got an error message:

> Task :test FAILED 
FAILURE: Build failed with an exception. 

and the HTML report says:

org.gradle.internal.exceptions.DefaultMultiCauseException: Multiple Failures (2 failures)  
java.lang.OutOfMemoryError: Java heap space  
java.lang.OutOfMemoryError: Java heap space 

Answer 1

Solved by adding configuration in build.gradle file:

test {
    minHeapSize = "800m"
    maxHeapSize = "2000m"
    ...