KAFKA-20297: Move AbstractIterator, CircularIterator, CloseableIterator... into internal (apache#22052)

We have exposed several classes in org.apache.kafka.common.utils as
public APIs, which can be misleading since not all classes in this
package are intended for external use.

To clarify API boundaries and prevent unintended usage, we propose
moving the following classes to an internal package:

- AbstractIterator
- CircularIterator
- CloseableIterator
- CopyOnWriteMap
- FixedOrderMap
- PrimitiveRef

Reviewers: Christo <lolovc@amazon.com>, PoAn Yang <payang@apache.org>

Author: m1a2st

clients/src/main/java/org/apache/kafka/clients/consumer/ConsumerRecords.java

@@ -17,7 +17,7 @@
 package org.apache.kafka.clients.consumer;
 
 import org.apache.kafka.common.TopicPartition;
-import org.apache.kafka.common.utils.AbstractIterator;
+import org.apache.kafka.common.utils.internals.AbstractIterator;
 
 import java.util.ArrayList;
 import java.util.Collections;

clients/src/main/java/org/apache/kafka/clients/consumer/RoundRobinAssignor.java

@@ -18,8 +18,8 @@
 
 import org.apache.kafka.clients.consumer.internals.AbstractPartitionAssignor;
 import org.apache.kafka.common.TopicPartition;
-import org.apache.kafka.common.utils.CircularIterator;
 import org.apache.kafka.common.utils.Utils;
+import org.apache.kafka.common.utils.internals.CircularIterator;
 
 import java.util.ArrayList;
 import java.util.HashMap;

clients/src/main/java/org/apache/kafka/clients/consumer/internals/CompletedFetch.java

@@ -35,7 +35,7 @@
 import org.apache.kafka.common.requests.FetchResponse;
 import org.apache.kafka.common.serialization.Deserializer;
 import org.apache.kafka.common.utils.BufferSupplier;
-import org.apache.kafka.common.utils.CloseableIterator;
+import org.apache.kafka.common.utils.internals.CloseableIterator;
 
 import org.slf4j.Logger;
 

clients/src/main/java/org/apache/kafka/clients/consumer/internals/ShareCompletedFetch.java

@@ -34,8 +34,8 @@
 import org.apache.kafka.common.requests.ShareFetchResponse;
 import org.apache.kafka.common.serialization.Deserializer;
 import org.apache.kafka.common.utils.BufferSupplier;
-import org.apache.kafka.common.utils.CloseableIterator;
 import org.apache.kafka.common.utils.LogContext;
+import org.apache.kafka.common.utils.internals.CloseableIterator;
 
 import org.slf4j.Logger;
 

clients/src/main/java/org/apache/kafka/clients/producer/internals/RecordAccumulator.java

@@ -35,10 +35,10 @@
 import org.apache.kafka.common.record.internal.MemoryRecordsBuilder;
 import org.apache.kafka.common.record.internal.Record;
 import org.apache.kafka.common.record.internal.RecordBatch;
-import org.apache.kafka.common.utils.CopyOnWriteMap;
 import org.apache.kafka.common.utils.LogContext;
 import org.apache.kafka.common.utils.ProducerIdAndEpoch;
 import org.apache.kafka.common.utils.Time;
+import org.apache.kafka.common.utils.internals.CopyOnWriteMap;
 import org.apache.kafka.common.utils.internals.ExponentialBackoff;
 
 import org.slf4j.Logger;

clients/src/main/java/org/apache/kafka/clients/producer/internals/TxnPartitionEntry.java

@@ -20,8 +20,8 @@
 import org.apache.kafka.common.TopicPartition;
 import org.apache.kafka.common.record.internal.DefaultRecordBatch;
 import org.apache.kafka.common.requests.ProduceResponse;
-import org.apache.kafka.common.utils.PrimitiveRef;
 import org.apache.kafka.common.utils.ProducerIdAndEpoch;
+import org.apache.kafka.common.utils.internals.PrimitiveRef;
 
 import java.util.Comparator;
 import java.util.OptionalInt;

clients/src/main/java/org/apache/kafka/common/header/internals/RecordHeaders.java

@@ -19,7 +19,7 @@
 import org.apache.kafka.common.header.Header;
 import org.apache.kafka.common.header.Headers;
 import org.apache.kafka.common.record.internal.Record;
-import org.apache.kafka.common.utils.AbstractIterator;
+import org.apache.kafka.common.utils.internals.AbstractIterator;
 
 import java.util.ArrayList;
 import java.util.Arrays;

clients/src/main/java/org/apache/kafka/common/record/internal/AbstractLegacyRecordBatch.java

@@ -22,12 +22,12 @@
 import org.apache.kafka.common.errors.CorruptRecordException;
 import org.apache.kafka.common.header.Header;
 import org.apache.kafka.common.record.TimestampType;
-import org.apache.kafka.common.utils.AbstractIterator;
 import org.apache.kafka.common.utils.BufferSupplier;
 import org.apache.kafka.common.utils.ByteBufferOutputStream;
-import org.apache.kafka.common.utils.CloseableIterator;
 import org.apache.kafka.common.utils.Utils;
+import org.apache.kafka.common.utils.internals.AbstractIterator;
 import org.apache.kafka.common.utils.internals.ByteUtils;
+import org.apache.kafka.common.utils.internals.CloseableIterator;
 
 import java.io.DataOutputStream;
 import java.io.IOException;

clients/src/main/java/org/apache/kafka/common/record/internal/AbstractRecords.java

@@ -17,8 +17,8 @@
 package org.apache.kafka.common.record.internal;
 
 import org.apache.kafka.common.header.Header;
-import org.apache.kafka.common.utils.AbstractIterator;
 import org.apache.kafka.common.utils.Utils;
+import org.apache.kafka.common.utils.internals.AbstractIterator;
 
 import java.nio.ByteBuffer;
 import java.util.Iterator;

clients/src/main/java/org/apache/kafka/common/record/internal/DefaultRecordBatch.java

@@ -24,9 +24,9 @@
 import org.apache.kafka.common.record.TimestampType;
 import org.apache.kafka.common.utils.BufferSupplier;
 import org.apache.kafka.common.utils.ByteBufferOutputStream;
-import org.apache.kafka.common.utils.CloseableIterator;
 import org.apache.kafka.common.utils.Crc32C;
 import org.apache.kafka.common.utils.internals.ByteUtils;
+import org.apache.kafka.common.utils.internals.CloseableIterator;
 
 import java.io.IOException;
 import java.io.InputStream;