HDDS-10422. Fix some warnings about exposing internal representation in hdds-common

hadoop-hdds/client/src/main/java/org/apache/hadoop/hdds/scm/XceiverClientMetrics.java

@@ -32,7 +32,6 @@
 import org.apache.hadoop.metrics2.lib.MutableCounterLong;
 import org.apache.hadoop.ozone.OzoneConfigKeys;
 import org.apache.hadoop.util.PerformanceMetrics;
-import org.apache.hadoop.util.PerformanceMetricsInitializer;
 
 /**
  * The client metrics for the Storage Container protocol.
@@ -76,7 +75,7 @@ public void init() {
               "number of" + ContainerProtos.Type.forNumber(i + 1) + " ops",
               (long) 0);
       containerOpsLatency[i] =
-          PerformanceMetricsInitializer.getMetrics(registry,
+          new PerformanceMetrics(registry,
               ContainerProtos.Type.forNumber(i + 1) + "Latency",
               "latency of " + ContainerProtos.Type.forNumber(i + 1),
               "Ops", "Time", intervals);

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/client/OzoneQuota.java

@@ -20,11 +20,6 @@
 
 import com.google.common.base.Strings;
 
-import static org.apache.hadoop.ozone.OzoneConsts.GB;
-import static org.apache.hadoop.ozone.OzoneConsts.KB;
-import static org.apache.hadoop.ozone.OzoneConsts.MB;
-import static org.apache.hadoop.ozone.OzoneConsts.TB;
-
 
 /**
  * represents an OzoneQuota Object that can be applied to
@@ -44,27 +39,17 @@ public enum Units { B, KB, MB, GB, TB }
   // Quota to decide how many buckets can be created.
   private long quotaInNamespace;
   // Quota to decide how many storage space will be used in bytes.
-  private long quotaInBytes;
-  private RawQuotaInBytes rawQuotaInBytes;
+  private final long quotaInBytes;
+  private final RawQuotaInBytes rawQuotaInBytes;
   // Data class of Quota.
-  private static QuotaList quotaList;
-
-  /** Setting QuotaList parameters from large to small. */
-  static {
-    quotaList = new QuotaList();
-    quotaList.addQuotaList(OZONE_QUOTA_TB, Units.TB, TB);
-    quotaList.addQuotaList(OZONE_QUOTA_GB, Units.GB, GB);
-    quotaList.addQuotaList(OZONE_QUOTA_MB, Units.MB, MB);
-    quotaList.addQuotaList(OZONE_QUOTA_KB, Units.KB, KB);
-    quotaList.addQuotaList(OZONE_QUOTA_B, Units.B, 1L);
-  }
+  private static final QuotaList QUOTA_LIST = new QuotaList();
 
   /**
    * Used to convert user input values into bytes such as: 1MB-> 1048576.
    */
   private static class RawQuotaInBytes {
-    private Units unit;
-    private long size;
+    private final Units unit;
+    private final long size;
 
     RawQuotaInBytes(Units unit, long size) {
       this.unit = unit;
@@ -84,9 +69,9 @@ public long getSize() {
      */
     public long sizeInBytes() {
       long sQuota = -1L;
-      for (Units quota : quotaList.getUnitQuotaArray()) {
+      for (Units quota : QUOTA_LIST.getUnitQuotaArray()) {
         if (quota == this.unit) {
-          sQuota = quotaList.getQuotaSize(quota);
+          sQuota = QUOTA_LIST.getQuotaSize(quota);
           break;
         }
       }
@@ -162,11 +147,11 @@ public static OzoneQuota parseSpaceQuota(String quotaInBytes) {
     Units currUnit = Units.B;
 
     try {
-      for (String quota : quotaList.getOzoneQuotaArray()) {
+      for (String quota : QUOTA_LIST.getOzoneQuotaArray()) {
         if (uppercase.endsWith((quota))) {
           size = uppercase
               .substring(0, uppercase.length() - quota.length());
-          currUnit = quotaList.getUnits(quota);
+          currUnit = QUOTA_LIST.getUnits(quota);
           break;
         }
       }
@@ -242,10 +227,10 @@ public static OzoneQuota getOzoneQuota(long quotaInBytes,
       long quotaInNamespace) {
     long size = 1L;
     Units unit = Units.B;
-    for (Long quota : quotaList.getSizeQuotaArray()) {
+    for (Long quota : QUOTA_LIST.getSizeQuotaArray()) {
       if (quotaInBytes % quota == 0) {
         size = quotaInBytes / quota;
-        unit = quotaList.getQuotaUnit(quota);
+        unit = QUOTA_LIST.getQuotaUnit(quota);
       }
     }
     return new OzoneQuota(quotaInNamespace, new RawQuotaInBytes(unit, size));

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/client/QuotaList.java

@@ -19,8 +19,14 @@
 package org.apache.hadoop.hdds.client;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 
+import static org.apache.hadoop.ozone.OzoneConsts.GB;
+import static org.apache.hadoop.ozone.OzoneConsts.KB;
+import static org.apache.hadoop.ozone.OzoneConsts.MB;
+import static org.apache.hadoop.ozone.OzoneConsts.TB;
+
 /**
  *This class contains arraylist for storage constant used in OzoneQuota.
  */
@@ -33,25 +39,32 @@ public QuotaList() {
     ozoneQuota = new ArrayList<>();
     unitQuota = new ArrayList<>();
     sizeQuota = new ArrayList<>();
+
+    // Setting QuotaList parameters from large to small.
+    addQuotaList(OzoneQuota.OZONE_QUOTA_TB, OzoneQuota.Units.TB, TB);
+    addQuotaList(OzoneQuota.OZONE_QUOTA_GB, OzoneQuota.Units.GB, GB);
+    addQuotaList(OzoneQuota.OZONE_QUOTA_MB, OzoneQuota.Units.MB, MB);
+    addQuotaList(OzoneQuota.OZONE_QUOTA_KB, OzoneQuota.Units.KB, KB);
+    addQuotaList(OzoneQuota.OZONE_QUOTA_B, OzoneQuota.Units.B, 1L);
   }
 
-  public void addQuotaList(
+  private void addQuotaList(
       String oQuota, OzoneQuota.Units uQuota, Long sQuota) {
     ozoneQuota.add(oQuota);
     unitQuota.add(uQuota);
     sizeQuota.add(sQuota);
   }
 
   public List<String> getOzoneQuotaArray() {
-    return this.ozoneQuota;
+    return Collections.unmodifiableList(this.ozoneQuota);
   }
 
   public List<Long> getSizeQuotaArray() {
-    return this.sizeQuota;
+    return Collections.unmodifiableList(this.sizeQuota);
   }
 
   public List<OzoneQuota.Units> getUnitQuotaArray() {
-    return this.unitQuota;
+    return Collections.unmodifiableList(this.unitQuota);
   }
 
   public OzoneQuota.Units getUnits(String oQuota) {

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/conf/OzoneConfiguration.java

@@ -30,6 +30,7 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.List;
@@ -163,15 +164,11 @@ public XMLConfiguration() {
     }
 
     public XMLConfiguration(List<Property> properties) {
-      this.properties = properties;
+      this.properties = new ArrayList<>(properties);
     }
 
     public List<Property> getProperties() {
-      return properties;
-    }
-
-    public void setProperties(List<Property> properties) {
-      this.properties = properties;
+      return Collections.unmodifiableList(properties);
     }
   }
 

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/freon/FakeClusterTopology.java

@@ -18,6 +18,7 @@
 package org.apache.hadoop.hdds.freon;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Random;
 import java.util.UUID;
@@ -36,20 +37,20 @@
  * Class to store pre-generated topology information for load-tests.
  */
 @SuppressWarnings("java:S2245") // no need for secure random
-public class FakeClusterTopology {
+public final class FakeClusterTopology {
 
   private static final Logger LOGGER =
       LoggerFactory.getLogger(FakeClusterTopology.class);
 
   public static final FakeClusterTopology INSTANCE = new FakeClusterTopology();
 
-  private List<DatanodeDetailsProto> datanodes = new ArrayList<>();
+  private final List<DatanodeDetailsProto> datanodes = new ArrayList<>();
 
-  private List<Pipeline> pipelines = new ArrayList<>();
+  private final List<Pipeline> pipelines = new ArrayList<>();
 
-  private Random random = new Random();
+  private final Random random = new Random();
 
-  public FakeClusterTopology() {
+  private FakeClusterTopology() {
     try {
       for (int i = 0; i < 9; i++) {
         datanodes.add(createDatanode());
@@ -87,7 +88,7 @@ public Pipeline getRandomPipeline() {
     return pipelines.get(random.nextInt(pipelines.size()));
   }
 
-  public List<DatanodeDetailsProto> getAllDatanodes() {
-    return datanodes;
+  public Iterable<DatanodeDetailsProto> getAllDatanodes() {
+    return Collections.unmodifiableList(datanodes);
   }
 }

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/protocol/DatanodeDetails.java

@@ -222,7 +222,7 @@ public synchronized void setPort(Name name, int port) {
    * @return DataNode Ports
    */
   public synchronized List<Port> getPorts() {
-    return ports;
+    return new ArrayList<>(ports);
   }
 
   /**

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/ScmInfo.java

@@ -19,24 +19,25 @@
 package org.apache.hadoop.hdds.scm;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 
 /**
  * ScmInfo wraps the result returned from SCM#getScmInfo which
  * contains clusterId and the SCM Id.
  */
 public final class ScmInfo {
-  private String clusterId;
-  private String scmId;
-  private List<String> peerRoles;
+  private final String clusterId;
+  private final String scmId;
+  private final List<String> peerRoles;
 
   /**
    * Builder for ScmInfo.
    */
   public static class Builder {
     private String clusterId;
     private String scmId;
-    private List<String> peerRoles;
+    private final List<String> peerRoles;
 
     public Builder() {
       peerRoles = new ArrayList<>();
@@ -104,6 +105,6 @@ public String getScmId() {
    * @return List of peer address
    */
   public List<String> getRatisPeerRoles() {
-    return peerRoles;
+    return Collections.unmodifiableList(peerRoles);
   }
 }

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/XceiverClientReply.java

@@ -22,6 +22,7 @@
 import org.apache.hadoop.hdds.protocol.datanode.proto.ContainerProtos
     .ContainerCommandResponseProto;
 
+import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.concurrent.CompletableFuture;
@@ -60,7 +61,7 @@ public void setLogIndex(long logIndex) {
   }
 
   public List<DatanodeDetails> getDatanodes() {
-    return datanodes;
+    return Collections.unmodifiableList(datanodes);
   }
 
   public void addDatanode(DatanodeDetails dn) {

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/container/common/helpers/ExcludeList.java

@@ -25,6 +25,7 @@
 import java.time.Clock;
 import java.time.ZoneOffset;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.Map;
@@ -38,28 +39,24 @@
  */
 public class ExcludeList {
 
-  private final Map<DatanodeDetails, Long> datanodes;
-  private final Set<ContainerID> containerIds;
-  private final Set<PipelineID> pipelineIds;
+  private final Map<DatanodeDetails, Long> datanodes = new ConcurrentHashMap<>();
+  private final Set<ContainerID> containerIds = new HashSet<>();
+  private final Set<PipelineID> pipelineIds = new HashSet<>();
   private long expiryTime = 0;
-  private java.time.Clock clock;
+  private final Clock clock;
 
 
   public ExcludeList() {
-    datanodes = new ConcurrentHashMap<>();
-    containerIds = new HashSet<>();
-    pipelineIds = new HashSet<>();
     clock = Clock.system(ZoneOffset.UTC);
   }
 
-  public ExcludeList(long autoExpiryTime, java.time.Clock clock) {
-    this();
+  public ExcludeList(long autoExpiryTime, Clock clock) {
     this.expiryTime = autoExpiryTime;
     this.clock = clock;
   }
 
   public Set<ContainerID> getContainerIds() {
-    return containerIds;
+    return Collections.unmodifiableSet(containerIds);
   }
 
   public Set<DatanodeDetails> getDatanodes() {
@@ -99,7 +96,7 @@ public void addPipeline(PipelineID pipelineId) {
   }
 
   public Set<PipelineID> getPipelineIds() {
-    return pipelineIds;
+    return Collections.unmodifiableSet(pipelineIds);
   }
 
   public HddsProtos.ExcludeListProto getProtoBuf() {

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/scm/ha/SCMHAUtils.java

@@ -65,7 +65,7 @@ public final class SCMHAUtils {
   public static final Logger LOG =
       LoggerFactory.getLogger(SCMHAUtils.class);
 
-  private static final List<Class<? extends Exception>>
+  private static final ImmutableList<Class<? extends Exception>>
       RETRIABLE_WITH_NO_FAILOVER_EXCEPTION_LIST =
       ImmutableList.<Class<? extends Exception>>builder()
           .add(LeaderNotReadyException.class)
@@ -74,7 +74,7 @@ public final class SCMHAUtils {
           .add(ResourceUnavailableException.class)
           .build();
 
-  private static final List<Class<? extends Exception>>
+  private static final ImmutableList<Class<? extends Exception>>
       NON_RETRIABLE_EXCEPTION_LIST =
       ImmutableList.<Class<? extends Exception>>builder()
           .add(SCMException.class)
@@ -316,7 +316,7 @@ public static Throwable getExceptionForClass(Exception e,
     return null;
   }
 
-  public static List<Class<? extends
+  private static List<Class<? extends
       Exception>> getRetriableWithNoFailoverExceptionList() {
     return RETRIABLE_WITH_NO_FAILOVER_EXCEPTION_LIST;
   }