Repository: apache/kafka
File: streams/src/test/java/org/apache/kafka/streams/internals/metrics/OpenIteratorsTest.java (Java)

Code before:
 */
package org.apache.kafka.streams.internals.metrics;

import org.apache.kafka.common.metrics.Gauge;
import org.apache.kafka.streams.processor.TaskId;
import org.apache.kafka.streams.processor.internals.metrics.StreamsMetricsImpl;
import org.apache.kafka.streams.state.internals.MeteredIterator;
import org.junit.jupiter.api.Test;
import org.mockito.ArgumentCaptor;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.not;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.never;
import static org.mockito.Mockito.reset;
import static org.mockito.Mockito.verify;

public class OpenIteratorsTest {

    private final StreamsMetricsImpl streamsMetrics = mock(StreamsMetricsImpl.class);

    @Test
    public void shouldCalculateOldestStartTimestampCorrectly() {
        final OpenIterators openIterators = new OpenIterators(new TaskId(1, 1), "2", "3", streamsMetrics);

        final MeteredIterator meteredIterator1 = () -> 5;
        final MeteredIterator meteredIterator2 = () -> 2;
        final MeteredIterator meteredIterator3 = () -> 6;

        openIterators.add(meteredIterator1);
        final ArgumentCaptor<Gauge<Long>> gaugeCaptor = ArgumentCaptor.forClass(Gauge.class);
        verify(streamsMetrics).addStoreLevelMutableMetric(any(), any(), any(), any(), any(), any(), gaugeCaptor.capture());
        final Gauge<Long> gauge = gaugeCaptor.getValue();
        assertThat(gauge.value(null, 0), is(5L));
        reset(streamsMetrics);

        openIterators.add(meteredIterator2);
        verify(streamsMetrics, never()).addStoreLevelMutableMetric(any(), any(), any(), any(), any(), any(), gaugeCaptor.capture());
        assertThat(gauge.value(null, 0), is(2L));

        openIterators.remove(meteredIterator2);
        verify(streamsMetrics, never()).removeMetric(any());
        assertThat(gauge.value(null, 0), is(5L));

        openIterators.remove(meteredIterator1);
        verify(streamsMetrics).removeMetric(any());
        assertThat(gauge.value(null, 0), is(5L));

        openIterators.add(meteredIterator3);

Review comment (suggestion):
```suggestion
    @SuppressWarnings("unchecked")
    @Test
```

Code after:
 */
package org.apache.kafka.streams.internals.metrics;

import org.apache.kafka.common.metrics.Gauge;
import org.apache.kafka.streams.processor.TaskId;
import org.apache.kafka.streams.processor.internals.metrics.StreamsMetricsImpl;
import org.apache.kafka.streams.state.internals.MeteredIterator;

import org.junit.jupiter.api.Test;
import org.mockito.ArgumentCaptor;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.not;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.never;
import static org.mockito.Mockito.reset;
import static org.mockito.Mockito.verify;

public class OpenIteratorsTest {

    private final StreamsMetricsImpl streamsMetrics = mock(StreamsMetricsImpl.class);

    @SuppressWarnings("unchecked")
    @Test
    public void shouldCalculateOldestStartTimestampCorrectly() {
        final OpenIterators openIterators = new OpenIterators(new TaskId(0, 0), "scope", "name", streamsMetrics);

        final MeteredIterator meteredIterator1 = () -> 5;
        final MeteredIterator meteredIterator2 = () -> 2;
        final MeteredIterator meteredIterator3 = () -> 6;

        openIterators.add(meteredIterator1);
        final ArgumentCaptor<Gauge<Long>> gaugeCaptor = ArgumentCaptor.forClass(Gauge.class);
        verify(streamsMetrics).addStoreLevelMutableMetric(any(), any(), any(), any(), any(), any(), gaugeCaptor.capture());
        final Gauge<Long> gauge = gaugeCaptor.getValue();
        assertThat(gauge.value(null, 0), is(5L));
        reset(streamsMetrics);

        openIterators.add(meteredIterator2);
        verify(streamsMetrics, never()).addStoreLevelMutableMetric(any(), any(), any(), any(), any(), any(), gaugeCaptor.capture());
        assertThat(gauge.value(null, 0), is(2L));

        openIterators.remove(meteredIterator2);
        verify(streamsMetrics, never()).removeMetric(any());
        assertThat(gauge.value(null, 0), is(5L));

        openIterators.remove(meteredIterator1);
        verify(streamsMetrics).removeMetric(any());
        assertThat(gauge.value(null, 0), is(5L));