KAFKA-12524: Remove deprecated segments() (#10379)

Reviewers: Boyang Chen <boyang@confluent.io>

docs/streams/upgrade-guide.html

@@ -92,6 +92,14 @@
       this restriction will be enforced. If you wish to run more than one instance of Kafka Streams, you must configure them with different values for <code>state.dir</code>.
     </p>
 
+    <h3><a id="streams_api_changes_300" href="#streams_api_changes_300">Streams API changes in 3.0.0</a></h3>
+    <p>
+        We removed the following deprecated APIs:
+    </p>
+    <ul>
+        <li> <code>WindowBytesStoreSupplier#segments</code>: deprecated in Kafka 2.1.0 (<a href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-319%3A+Replace+segments+with+segmentInterval+in+WindowBytesStoreSupplier">KIP-319</a>).</li>
+    </ul>
+
     <h3><a id="streams_api_changes_280" href="#streams_api_changes_280">Streams API changes in 2.8.0</a></h3>
     <p>
         We extended <code>StreamJoined</code> to include the options <code>withLoggingEnabled()</code> and <code>withLoggingDisabled()</code> in

streams/src/main/java/org/apache/kafka/streams/state/WindowBytesStoreSupplier.java

@@ -27,16 +27,6 @@ import org.apache.kafka.common.utils.Bytes;
  * 2. Null value bytes should never be returned in range query results.
  */
 public interface WindowBytesStoreSupplier extends StoreSupplier<WindowStore<Bytes, byte[]>> {
-    /**
-     * The number of segments the store has. If your store is segmented then this should be the number of segments
-     * in the underlying store.
-     * It is also used to reduce the amount of data that is scanned when caching is enabled.
-     *
-     * @return number of segments
-     * @deprecated since 2.1. Use {@link WindowBytesStoreSupplier#segmentIntervalMs()} instead.
-     */
-    @Deprecated
-    int segments();
 
     /**
      * The size of the segments (in milliseconds) the store has.

streams/src/main/java/org/apache/kafka/streams/state/internals/InMemoryWindowBytesStoreSupplier.java

@@ -55,12 +55,6 @@ public class InMemoryWindowBytesStoreSupplier implements WindowBytesStoreSupplie
         return "in-memory-window";
     }
 
-    @Deprecated
-    @Override
-    public int segments() {
-        throw new IllegalStateException("Segments is deprecated and should not be called");
-    }
-
     @Override
     public long retentionPeriod() {
         return retentionPeriod;

streams/src/main/java/org/apache/kafka/streams/state/internals/RocksDbWindowBytesStoreSupplier.java

@@ -77,12 +77,6 @@ public class RocksDbWindowBytesStoreSupplier implements WindowBytesStoreSupplier
         return "rocksdb-window";
     }
 
-    @Deprecated
-    @Override
-    public int segments() {
-        return (int) (retentionPeriod / segmentInterval) + 1;
-    }
-
     @Override
     public long segmentIntervalMs() {
         return segmentInterval;