KAFKA-19305 Make ClientQuotaImage and TopicImage immutable (#19847)

- Updated `ClientQuotaImage` and `TopicImage` by using
`Collections.unmodifiableMap` or `ImmutableMap` to prevent accidental or
intentional mutations after construction.

Reviewers: Alyssa Huang <[email protected]>, Chia-Ping Tsai
 <[email protected]>

Author: jim0987795064

metadata/src/main/java/org/apache/kafka/image/ClientQuotaImage.java

@@ -31,29 +31,18 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
-import java.util.Objects;
 
 
 /**
  * Represents a quota for a client entity in the metadata image.
  *
  * This class is thread-safe.
  */
-public final class ClientQuotaImage {
+public record ClientQuotaImage(Map<String, Double> quotas) {
     public static final ClientQuotaImage EMPTY = new ClientQuotaImage(Map.of());
 
-    private final Map<String, Double> quotas;
-
-    public ClientQuotaImage(Map<String, Double> quotas) {
-        this.quotas = quotas;
-    }
-
-    Map<String, Double> quotas() {
-        return quotas;
-    }
-
-    public Map<String, Double> quotaMap() {
-        return Collections.unmodifiableMap(quotas);
+    public ClientQuotaImage {
+        quotas = Collections.unmodifiableMap(quotas);
     }
 
     public void write(
@@ -100,17 +89,6 @@ public boolean isEmpty() {
         return quotas.isEmpty();
     }
 
-    @Override
-    public boolean equals(Object o) {
-        if (!(o instanceof ClientQuotaImage other)) return false;
-        return quotas.equals(other.quotas);
-    }
-
-    @Override
-    public int hashCode() {
-        return Objects.hash(quotas);
-    }
-
     @Override
     public String toString() {
         return new ClientQuotaImageNode(this).stringify();

metadata/src/main/java/org/apache/kafka/image/TopicImage.java

@@ -24,41 +24,19 @@
 import org.apache.kafka.image.writer.ImageWriterOptions;
 import org.apache.kafka.metadata.PartitionRegistration;
 
+import java.util.Collections;
 import java.util.Map;
 import java.util.Map.Entry;
-import java.util.Objects;
 
 
 /**
  * Represents a topic in the metadata image.
  *
  * This class is thread-safe.
  */
-public final class TopicImage {
-    private final String name;
-
-    private final Uuid id;
-
-    private final Map<Integer, PartitionRegistration> partitions;
-
-    public TopicImage(String name,
-                      Uuid id,
-                      Map<Integer, PartitionRegistration> partitions) {
-        this.name = name;
-        this.id = id;
-        this.partitions = partitions;
-    }
-
-    public String name() {
-        return name;
-    }
-
-    public Uuid id() {
-        return id;
-    }
-
-    public Map<Integer, PartitionRegistration> partitions() {
-        return partitions;
+public record TopicImage(String name, Uuid id, Map<Integer, PartitionRegistration> partitions) {
+    public TopicImage {
+        partitions = Collections.unmodifiableMap(partitions);
     }
 
     public void write(ImageWriter writer, ImageWriterOptions options) {
@@ -72,19 +50,6 @@ public void write(ImageWriter writer, ImageWriterOptions options) {
         }
     }
 
-    @Override
-    public boolean equals(Object o) {
-        if (!(o instanceof TopicImage other)) return false;
-        return name.equals(other.name) &&
-            id.equals(other.id) &&
-            partitions.equals(other.partitions);
-    }
-
-    @Override
-    public int hashCode() {
-        return Objects.hash(name, id, partitions);
-    }
-
     @Override
     public String toString() {
         return new TopicImageNode(this).stringify();

metadata/src/main/java/org/apache/kafka/image/node/ClientQuotaImageNode.java

@@ -34,12 +34,12 @@ public ClientQuotaImageNode(ClientQuotaImage image) {
 
     @Override
     public Collection<String> childNames() {
-        return image.quotaMap().keySet();
+        return image.quotas().keySet();
     }
 
     @Override
     public MetadataNode child(String name) {
-        Double result = image.quotaMap().get(name);
+        Double result = image.quotas().get(name);
         if (result == null) return null;
         return new MetadataLeafNode(result + "");
     }