HDDS-12889. Enable AppendCharacterWithChar PMD rule

dev-support/pmd/pmd-ruleset.xml

@@ -35,6 +35,7 @@
   <rule ref="category/java/bestpractices.xml/SimplifiableTestAssertion" />
 
   <rule ref="category/java/performance.xml/AddEmptyString"/>
+  <rule ref="category/java/performance.xml/AppendCharacterWithChar" />
   <rule ref="category/java/performance.xml/AvoidFileStream"/>
   <rule ref="category/java/performance.xml/InefficientEmptyStringCheck"/>
   <rule ref="category/java/performance.xml/InefficientStringBuffering"/>

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/HddsUtils.java

@@ -845,7 +845,7 @@ public static HddsProtos.UUID toProtobuf(UUID uuid) {
     if (elements != null && elements.length > startIndex) {
       final StringBuilder sb = new StringBuilder();
       for (int line = startIndex; line < elements.length; line++) {
-        sb.append(elements[line]).append("\n");
+        sb.append(elements[line]).append('\n');
       }
       return sb.toString();
     }

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/NodeDetails.java

@@ -105,7 +105,7 @@ public String getHostAddress() {
   public String getRatisHostPortStr() {
     StringBuilder hostPort = new StringBuilder();
     hostPort.append(getHostName())
-        .append(":")
+        .append(':')
         .append(ratisPort);
     return hostPort.toString();
   }

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

@@ -182,7 +182,7 @@ public static List<SCMNodeInfo> buildNodeInfo(ConfigurationSource conf) {
   }
 
   private static String buildAddress(String address, int port) {
-    return new StringBuilder().append(address).append(":")
+    return new StringBuilder().append(address).append(':')
         .append(port).toString();
   }
 

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

@@ -893,18 +893,18 @@ public String toString() {
     StringBuilder tree = new StringBuilder();
     tree.append("Level: ");
     tree.append(maxLevel);
-    tree.append("\n");
+    tree.append('\n');
     netlock.readLock().lock();
     try {
       // print the number of leaves
       int numOfLeaves = clusterTree.getNumOfLeaves();
       tree.append("Number of leaves:");
       tree.append(numOfLeaves);
-      tree.append("\n");
+      tree.append('\n');
       // print all nodes
       for (int i = 0; i < numOfLeaves; i++) {
         tree.append(clusterTree.getLeaf(i).getNetworkFullPath());
-        tree.append("\n");
+        tree.append('\n');
       }
     } finally {
       netlock.readLock().unlock();

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

@@ -521,20 +521,20 @@ public int hashCode() {
   @Override
   public String toString() {
     final StringBuilder b =
-        new StringBuilder(getClass().getSimpleName()).append("{");
+        new StringBuilder(getClass().getSimpleName()).append('{');
     b.append(" Id: ").append(id.getId());
     b.append(", Nodes: [");
     for (DatanodeDetails datanodeDetails : nodeStatus.keySet()) {
       b.append(" {").append(datanodeDetails);
       b.append(", ReplicaIndex: ").append(this.getReplicaIndex(datanodeDetails)).append("},");
     }
-    b.append("]");
+    b.append(']');
     b.append(", ReplicationConfig: ").append(replicationConfig);
     b.append(", State:").append(getPipelineState());
     b.append(", leaderId:").append(leaderId != null ? leaderId.toString() : "");
     b.append(", CreationTimestamp").append(getCreationTimestamp()
         .atZone(ZoneId.systemDefault()));
-    b.append("}");
+    b.append('}');
     return b.toString();
   }
 

hadoop-hdds/common/src/main/java/org/apache/hadoop/hdds/tracing/StringCodec.java

@@ -70,9 +70,9 @@ public JaegerSpanContext extract(StringBuilder s) {
   public void inject(JaegerSpanContext context, StringBuilder string) {
     int intFlag = context.getFlags() & 255;
     string.append(context.getTraceId())
-        .append(":").append(Long.toHexString(context.getSpanId()))
-        .append(":").append(Long.toHexString(context.getParentId()))
-        .append(":").append(Integer.toHexString(intFlag));
+        .append(':').append(Long.toHexString(context.getSpanId()))
+        .append(':').append(Long.toHexString(context.getParentId()))
+        .append(':').append(Integer.toHexString(intFlag));
   }
 
   private static long high(String hexString) {

hadoop-hdds/common/src/main/java/org/apache/hadoop/ozone/container/common/helpers/BlockData.java

@@ -279,7 +279,7 @@ public void appendTo(StringBuilder sb) {
     sb.append("[blockId=");
     blockID.appendTo(sb);
     sb.append(", size=").append(size);
-    sb.append("]");
+    sb.append(']');
   }
 
   public long getBlockGroupLength() {

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/helpers/BlockDeletingServiceMetrics.java

@@ -206,22 +206,22 @@ public long getProcessedTransactionFailCount() {
   @Override
   public String toString() {
     StringBuilder buffer = new StringBuilder()
-        .append("successCount = ").append(successCount.value()).append("\t")
-        .append("successBytes = ").append(successBytes.value()).append("\t")
-        .append("failureCount = ").append(failureCount.value()).append("\t")
+        .append("successCount = ").append(successCount.value()).append('\t')
+        .append("successBytes = ").append(successBytes.value()).append('\t')
+        .append("failureCount = ").append(failureCount.value()).append('\t')
         .append("outOfOrderDeleteBlockTransactionCount = ")
-        .append(outOfOrderDeleteBlockTransactionCount.value()).append("\t")
-        .append("totalPendingBlockCount = ").append(totalPendingBlockCount.value()).append("\t")
-        .append("totalBlockChosenCount = ").append(totalBlockChosenCount.value()).append("\t")
-        .append("totalContainerChosenCount = ").append(totalContainerChosenCount.value()).append("\t")
-        .append("receivedTransactionCount = ").append(receivedTransactionCount.value()).append("\t")
-        .append("receivedRetryTransactionCount = ").append(receivedRetryTransactionCount.value()).append("\t")
-        .append("processedTransactionSuccessCount = ").append(processedTransactionSuccessCount.value()).append("\t")
-        .append("processedTransactionFailCount = ").append(processedTransactionFailCount.value()).append("\t")
-        .append("receivedContainerCount = ").append(receivedContainerCount.value()).append("\t")
-        .append("receivedBlockCount = ").append(receivedBlockCount.value()).append("\t")
-        .append("markedBlockCount = ").append(markedBlockCount.value()).append("\t")
-        .append("totalLockTimeoutTransactionCount = ").append(totalLockTimeoutTransactionCount.value()).append("\t");
+        .append(outOfOrderDeleteBlockTransactionCount.value()).append('\t')
+        .append("totalPendingBlockCount = ").append(totalPendingBlockCount.value()).append('\t')
+        .append("totalBlockChosenCount = ").append(totalBlockChosenCount.value()).append('\t')
+        .append("totalContainerChosenCount = ").append(totalContainerChosenCount.value()).append('\t')
+        .append("receivedTransactionCount = ").append(receivedTransactionCount.value()).append('\t')
+        .append("receivedRetryTransactionCount = ").append(receivedRetryTransactionCount.value()).append('\t')
+        .append("processedTransactionSuccessCount = ").append(processedTransactionSuccessCount.value()).append('\t')
+        .append("processedTransactionFailCount = ").append(processedTransactionFailCount.value()).append('\t')
+        .append("receivedContainerCount = ").append(receivedContainerCount.value()).append('\t')
+        .append("receivedBlockCount = ").append(receivedBlockCount.value()).append('\t')
+        .append("markedBlockCount = ").append(markedBlockCount.value()).append('\t')
+        .append("totalLockTimeoutTransactionCount = ").append(totalLockTimeoutTransactionCount.value()).append('\t');
     return buffer.toString();
   }
 }

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/helpers/DeletedContainerBlocksSummary.java

@@ -99,7 +99,7 @@ public String getTxIDSummary() {
   @Override public String toString() {
     StringBuffer sb = new StringBuffer();
     for (DeletedBlocksTransaction blks : blocks) {
-      sb.append(" ")
+      sb.append(' ')
           .append("TXID=")
           .append(blks.getTxID())
           .append(", ")
@@ -108,8 +108,8 @@ public String getTxIDSummary() {
           .append(", ")
           .append(blks.getContainerID())
           .append(" : [")
-          .append(StringUtils.join(',', blks.getLocalIDList())).append("]")
-          .append("\n");
+          .append(StringUtils.join(',', blks.getLocalIDList())).append(']')
+          .append('\n');
     }
     return sb.toString();
   }

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/impl/StorageLocationReport.java

@@ -235,7 +235,7 @@ public static StorageLocationReport getFromProtobuf(StorageReportProto report)
   @Override
   public String toString() {
     StringBuilder sb = new StringBuilder(128)
-        .append("{")
+        .append('{')
         .append(" id=").append(id)
         .append(" dir=").append(storageLocation)
         .append(" type=").append(storageType);

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/ec/reconstruction/ECReconstructionCoordinator.java

@@ -373,7 +373,7 @@ private void logBlockGroupDetails(BlockLocationInfo blockLocationInfo,
       int cnt = 0;
       for (ContainerProtos.ChunkInfo chunkInfo : data.getChunks()) {
         if (cnt > 0) {
-          sb.append("\n");
+          sb.append('\n');
         }
         sb.append("  chunkNum: ")
             .append(++cnt)

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/keyvalue/KeyValueHandler.java

@@ -1427,7 +1427,7 @@ private boolean logBlocksFoundOnDisk(Container container) throws IOException {
       StringBuilder stringBuilder = new StringBuilder();
       for (Path block : dir) {
         if (notEmpty) {
-          stringBuilder.append(",");
+          stringBuilder.append(',');
         }
         stringBuilder.append(block);
         notEmpty = true;

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/replication/AbstractReplicationTask.java

@@ -144,7 +144,7 @@ protected Object getCommandForDebug() {
   @Override
   public String toString() {
     StringBuilder sb = new StringBuilder()
-        .append(getStatus()).append(" ")
+        .append(getStatus()).append(' ')
         .append(getCommandForDebug());
     if (getStatus() == Status.QUEUED) {
       sb.append(", queued at ").append(getQueued());

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/CloseContainerCommand.java

@@ -90,7 +90,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline())
         .append(", containerID: ").append(getContainerID())

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/ClosePipelineCommand.java

@@ -75,7 +75,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline())
         .append(", pipelineID: ").append(getPipelineID());

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/CreatePipelineCommand.java

@@ -159,7 +159,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline())
         .append(", pipelineID: ").append(getPipelineID())

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/DeleteBlocksCommand.java

@@ -69,7 +69,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline())
         .append(", deletedBlocksTransaction: [");
@@ -83,7 +83,7 @@ public String toString() {
     if (!blocksTobeDeleted.isEmpty()) {
       sb.delete(sb.length() - 2, sb.length());
     }
-    sb.append("]");
+    sb.append(']');
     return sb.toString();
   }
 }

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/DeleteContainerCommand.java

@@ -108,7 +108,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline())
         .append(", containerID: ").append(getContainerID())

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/FinalizeNewLayoutVersionCommand.java

@@ -78,7 +78,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline())
         .append(", finalizeUpgrade: ").append(finalizeUpgrade)

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/ReconstructECContainersCommand.java

@@ -131,15 +131,15 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline())
         .append(", containerID: ").append(containerID)
         .append(", replicationConfig: ").append(ecReplicationConfig)
         .append(", sources: [").append(getSources().stream()
             .map(a -> a.dnDetails
                 + " replicaIndex: " + a.getReplicaIndex())
-            .collect(Collectors.joining(", "))).append("]")
+            .collect(Collectors.joining(", "))).append(']')
         .append(", targets: ").append(getTargetDatanodes())
         .append(", missingIndexes: ").append(
             Arrays.toString(missingContainerIndexes.toByteArray()));

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/RefreshVolumeUsageCommand.java

@@ -60,7 +60,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline());
     return sb.toString();

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/ReplicateContainerCommand.java

@@ -159,7 +159,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType());
     sb.append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline());
     sb.append(", containerId=").append(getContainerID());

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/ReregisterCommand.java

@@ -59,7 +59,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline());
     return sb.toString();

hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/protocol/commands/SetNodeOperationalStateCommand.java

@@ -91,7 +91,7 @@ public String toString() {
     StringBuilder sb = new StringBuilder();
     sb.append(getType())
         .append(": cmdID: ").append(getId())
-        .append(", encodedToken: \"").append(getEncodedToken()).append("\"")
+        .append(", encodedToken: \"").append(getEncodedToken()).append('"')
         .append(", term: ").append(getTerm())
         .append(", deadlineMsSinceEpoch: ").append(getDeadline())
         .append(", opState: ").append(opState)

hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/common/utils/TestHddsVolumeUtil.java

@@ -73,7 +73,7 @@ public void setup() throws Exception {
     for (int i = 0; i < VOLUMNE_NUM; i++) {
       hddsVolumeDirs[i] =
           Files.createDirectory(tempDir.resolve("volumeDir" + i)).toFile();
-      hddsDirs.append(hddsVolumeDirs[i]).append(",");
+      hddsDirs.append(hddsVolumeDirs[i]).append(',');
     }
     conf.set(ScmConfigKeys.HDDS_DATANODE_DIR_KEY, hddsDirs.toString());
     hddsVolumeSet = new MutableVolumeSet(datanodeId, clusterId, conf, null,
@@ -85,7 +85,7 @@ public void setup() throws Exception {
     for (int i = 0; i < VOLUMNE_NUM; i++) {
       dbVolumeDirs[i] =
           Files.createDirectory(tempDir.resolve("dbVolumeDir" + i)).toFile();
-      dbDirs.append(dbVolumeDirs[i]).append(",");
+      dbDirs.append(dbVolumeDirs[i]).append(',');
     }
     conf.set(OzoneConfigKeys.HDDS_DATANODE_CONTAINER_DB_DIR,
         dbDirs.toString());

hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/common/volume/TestDbVolume.java

@@ -164,7 +164,7 @@ private MutableVolumeSet createHddsVolumeSet(int volumeNum)
     for (int i = 0; i < volumeNum; i++) {
       hddsVolumeDirs[i] =
           Files.createDirectory(folder.resolve("volumeDir" + i)).toFile();
-      hddsDirs.append(hddsVolumeDirs[i]).append(",");
+      hddsDirs.append(hddsVolumeDirs[i]).append(',');
     }
     CONF.set(ScmConfigKeys.HDDS_DATANODE_DIR_KEY, hddsDirs.toString());
     MutableVolumeSet hddsVolumeSet = new MutableVolumeSet(DATANODE_UUID,

hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/ozoneimpl/TestContainerReader.java

@@ -375,7 +375,7 @@ public void testMultipleContainerReader(ContainerTestVersionInfo versionInfo)
     for (int i = 0; i < volumeNum; i++) {
       volumeDirs[i] =
           Files.createDirectory(tempDir.resolve("volumeDir" + i)).toFile();
-      datanodeDirs = datanodeDirs.append(volumeDirs[i]).append(",");
+      datanodeDirs = datanodeDirs.append(volumeDirs[i]).append(',');
     }
 
     BlockUtils.shutdownCache(conf);

hadoop-hdds/container-service/src/test/java/org/apache/hadoop/ozone/container/ozoneimpl/TestOzoneContainer.java

@@ -189,7 +189,7 @@ public void testBuildNodeReport(ContainerTestVersionInfo versionInfo)
     for (int i = 0; i < 3; i++) {
       dbPaths[i] =
           Files.createDirectory(folder.resolve(Integer.toString(i))).toFile();
-      dbDirString.append(dbPaths[i]).append(",");
+      dbDirString.append(dbPaths[i]).append(',');
     }
     conf.set(OzoneConfigKeys.HDDS_DATANODE_CONTAINER_DB_DIR,
         dbDirString.toString());

hadoop-hdds/erasurecode/src/test/java/org/apache/ozone/erasurecode/TestCoderBase.java

@@ -482,15 +482,15 @@ protected void dumpSetting() {
       StringBuilder sb = new StringBuilder("Erasure coder test settings:\n");
       sb.append(" numDataUnits=").append(numDataUnits);
       sb.append(" numParityUnits=").append(numParityUnits);
-      sb.append(" chunkSize=").append(chunkSize).append("\n");
+      sb.append(" chunkSize=").append(chunkSize).append('\n');
 
       sb.append(" erasedDataIndexes=").
           append(Arrays.toString(erasedDataIndexes));
       sb.append(" erasedParityIndexes=").
           append(Arrays.toString(erasedParityIndexes));
       sb.append(" usingDirectBuffer=").append(usingDirectBuffer);
       sb.append(" allowVerboseDump=").append(allowDump);
-      sb.append("\n");
+      sb.append('\n');
 
       System.out.println(sb.toString());
     }

hadoop-hdds/erasurecode/src/test/java/org/apache/ozone/erasurecode/rawcoder/RawErasureCoderBenchmark.java

@@ -85,7 +85,7 @@ private static void printAvailableCoders() {
     StringBuilder sb = new StringBuilder(
         "Available coders with coderIndex:\n");
     for (CODER coder : CODER.values()) {
-      sb.append(coder.ordinal()).append(":").append(coder).append("\n");
+      sb.append(coder.ordinal()).append(':').append(coder).append('\n');
     }
     System.out.println(sb);
   }

hadoop-hdds/framework/src/main/java/org/apache/hadoop/hdds/server/http/HttpServer2.java

@@ -1410,7 +1410,7 @@ public String toString() {
             : STATE_DESCRIPTION_NOT_LIVE)
         .append("), listening at:");
     for (ServerConnector l : listeners) {
-      sb.append(l.getHost()).append(":").append(l.getPort()).append("/,");
+      sb.append(l.getHost()).append(':').append(l.getPort()).append("/,");
     }
     return sb.toString();
   }