/**
 * Base class for {@code ProgressEvent} implementations.
 */
public abstract class BaseProgressEvent implements ProgressEvent {

    private final long eventTime;
    private final String displayName;
    private final OperationDescriptor descriptor;

    protected BaseProgressEvent(long eventTime, String displayName, OperationDescriptor descriptor) {
        this.eventTime = eventTime;

import org.gradle.tooling.events.OperationDescriptor;
import org.gradle.tooling.events.internal.BaseProgressEvent;
import org.gradle.tooling.events.problems.ProblemAggregation;
import org.gradle.tooling.events.problems.ProblemAggregationEvent;

import javax.annotation.Nullable;

public class DefaultProblemAggregationEvent extends BaseProgressEvent implements ProblemAggregationEvent {

    private final ProblemAggregation problemAggregation;

 */

package org.gradle.tooling.events.problems.internal;

import org.gradle.api.NonNullApi;
import org.gradle.tooling.events.OperationDescriptor;
import org.gradle.tooling.events.internal.BaseProgressEvent;
import org.gradle.tooling.events.problems.AdditionalData;
import org.gradle.tooling.events.problems.ContextualLabel;
import org.gradle.tooling.events.problems.Details;

import org.gradle.tooling.events.OperationDescriptor;
import org.gradle.tooling.events.StartEvent;

/**
 * Base implementation of the {@code StartEvent} interface.
 */
public class DefaultStartEvent extends BaseProgressEvent implements StartEvent {

    public DefaultStartEvent(long eventTime, String displayName, OperationDescriptor descriptor) {
        super(eventTime, displayName, descriptor);
    }

import org.gradle.tooling.events.OperationDescriptor;
import org.gradle.tooling.events.StatusEvent;

/**
 * Base implementation of the {@code StatusEvent} interface.
 */
public class DefaultStatusEvent extends BaseProgressEvent implements StatusEvent {

    private final long total;
    private final long progress;
    private final String unit;

import org.gradle.tooling.events.OperationResult;

/**
 * Base implementation of the {@code FinishEvent} interface.
 */
public class DefaultFinishEvent<D extends OperationDescriptor, R extends OperationResult> extends BaseProgressEvent implements FinishEvent {

    private final R result;

    public DefaultFinishEvent(long eventTime, String displayName, D descriptor, R result) {
        super(eventTime, displayName, descriptor);

Class <org.gradle.tooling.events.internal.BaseProgressEvent> is not annotated (directly or via its package) with @org.gradle.api.NonNullApi in (BaseProgressEvent.java:0)