diff --git a/hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/master/BackupLogCleaner.java b/hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/master/BackupLogCleaner.java index a8ece39..cdab4a9 100644 --- a/hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/master/BackupLogCleaner.java +++ b/hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/master/BackupLogCleaner.java @@ -20,6 +20,7 @@ package org.apache.hadoop.hbase.backup.master; import java.io.IOException; import java.util.ArrayList; +import java.util.Collections; import java.util.List; import java.util.Map; @@ -116,7 +117,7 @@ public class BackupLogCleaner extends BaseLogCleanerDelegate { } catch (IOException e) { LOG.error("Failed to get backup system table table, therefore will keep all files", e); // nothing to delete - return new ArrayList(); + return Collections.emptyList(); } } diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ProtobufUtil.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ProtobufUtil.java index 7a5efb1..1baef59 100644 --- a/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ProtobufUtil.java +++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ProtobufUtil.java @@ -435,7 +435,7 @@ public final class ProtobufUtil { */ public static List toTableDescriptorList(GetTableDescriptorsResponse proto) { if (proto == null) { - return new ArrayList<>(); + return Collections.emptyList(); } return proto.getTableSchemaList().stream().map(ProtobufUtil::toTableDescriptor) .collect(Collectors.toList()); @@ -448,7 +448,7 @@ public final class ProtobufUtil { */ public static List toTableDescriptorList(ListTableDescriptorsByNamespaceResponse proto) { - if (proto == null) return new ArrayList<>(); + if (proto == null) Collections.emptyList(); return proto.getTableSchemaList().stream().map(ProtobufUtil::toTableDescriptor) .collect(Collectors.toList()); } @@ -2276,7 +2276,7 @@ public final class ProtobufUtil { public static List toTableNameList(List tableNamesList) { if (tableNamesList == null) { - return new ArrayList<>(); + return Collections.emptyList(); } return tableNamesList.stream().map(ProtobufUtil::toTableName).collect(Collectors.toList()); } diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/util/ByteRangeUtils.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/util/ByteRangeUtils.java index 90f3bf3..a691d1b 100644 --- a/hbase-common/src/main/java/org/apache/hadoop/hbase/util/ByteRangeUtils.java +++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/util/ByteRangeUtils.java @@ -22,6 +22,8 @@ import java.io.IOException; import java.io.OutputStream; import java.util.ArrayList; import java.util.Collection; +import java.util.Collections; +import java.util.List; import org.apache.yetus.audience.InterfaceAudience; @@ -45,9 +47,9 @@ public class ByteRangeUtils { return maxCompares; } - public static ArrayList copyToNewArrays(Collection ranges) { + public static List copyToNewArrays(Collection ranges) { if (ranges == null) { - return new ArrayList<>(0); + return Collections.emptyList(); } ArrayList arrays = Lists.newArrayListWithCapacity(ranges.size()); for (ByteRange range : ranges) { @@ -56,9 +58,9 @@ public class ByteRangeUtils { return arrays; } - public static ArrayList fromArrays(Collection arrays) { + public static List fromArrays(Collection arrays) { if (arrays == null) { - return new ArrayList<>(0); + return Collections.emptyList(); } ArrayList ranges = Lists.newArrayListWithCapacity(arrays.size()); for (byte[] array : arrays) { diff --git a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/RESTServer.java b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/RESTServer.java index 3033f18..c5d8c47 100644 --- a/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/RESTServer.java +++ b/hbase-rest/src/main/java/org/apache/hadoop/hbase/rest/RESTServer.java @@ -20,6 +20,7 @@ package org.apache.hadoop.hbase.rest; import java.lang.management.ManagementFactory; import java.util.ArrayList; +import java.util.Collections; import java.util.List; import java.util.Map; import java.util.EnumSet; @@ -116,7 +117,7 @@ public class RESTServer implements Constants { String name, String defaultValue) { String valueString = conf.get(name, defaultValue); if (valueString == null) { - return new ArrayList<>(); + return Collections.emptyList(); } return new ArrayList<>(StringUtils.getTrimmedStringCollection(valueString)); } diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignmentManager.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignmentManager.java index 1b8e757..cef4286 100644 --- a/hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignmentManager.java +++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignmentManager.java @@ -518,7 +518,7 @@ public class AssignmentManager implements ServerListener { private List getCarryingSystemTables(ServerName serverName) { Set regions = this.getRegionStates().getServerNode(serverName).getRegions(); if (regions == null) { - return new ArrayList<>(); + return Collections.emptyList(); } return regions.stream() .map(RegionStateNode::getRegionInfo) @@ -1853,7 +1853,7 @@ public class AssignmentManager implements ServerListener { .map((s)->new Pair<>(s, master.getRegionServerVersion(s))) .collect(Collectors.toList()); if (serverList.isEmpty()) { - return new ArrayList<>(); + return Collections.emptyList(); } String highestVersion = Collections.max(serverList, (o1, o2) -> VersionInfo.compareVersion(o1.getSecond(), o2.getSecond())).getSecond(); diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/BaseRowProcessor.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/BaseRowProcessor.java index da691b7..9111e4f 100644 --- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/BaseRowProcessor.java +++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/BaseRowProcessor.java @@ -19,6 +19,7 @@ package org.apache.hadoop.hbase.regionserver; import java.io.IOException; import java.util.ArrayList; +import java.util.Collections; import java.util.List; import java.util.Locale; import java.util.UUID; @@ -57,7 +58,7 @@ implements RowProcessor { @Override public List getClusterIds() { - return new ArrayList<>(); + return Collections.emptyList(); } @Override diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StripeStoreFileManager.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StripeStoreFileManager.java index ecd980a..11b01a6 100644 --- a/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StripeStoreFileManager.java +++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StripeStoreFileManager.java @@ -996,7 +996,7 @@ public class StripeStoreFileManager @Override public List getStripeBoundaries() { - if (this.state.stripeFiles.isEmpty()) return new ArrayList<>(); + if (this.state.stripeFiles.isEmpty()) Collections.emptyList(); ArrayList result = new ArrayList<>(this.state.stripeEndRows.length + 2); result.add(OPEN_KEY); Collections.addAll(result, this.state.stripeEndRows); diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/tool/Canary.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/tool/Canary.java index a012a4e..ab18929 100644 --- a/hbase-server/src/main/java/org/apache/hadoop/hbase/tool/Canary.java +++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/tool/Canary.java @@ -1258,7 +1258,7 @@ public final class Canary implements Tool { try { table = admin.getConnection().getTable(tableDesc.getTableName()); } catch (TableNotFoundException e) { - return new ArrayList<>(); + return Collections.emptyList(); } finally { if (table !=null) { diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/FSUtils.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/FSUtils.java index c0b72aa..f1a6531 100644 --- a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/FSUtils.java +++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/FSUtils.java @@ -1018,7 +1018,7 @@ public abstract class FSUtils extends CommonFSUtils { // assumes we are in a table dir. List rds = listStatusWithStatusFilter(fs, tableDir, new RegionDirFilter(fs)); if (rds == null) { - return new ArrayList<>(); + return Collections.emptyList(); } List regionDirs = new ArrayList<>(rds.size()); for (FileStatus rdfs: rds) { @@ -1081,7 +1081,7 @@ public abstract class FSUtils extends CommonFSUtils { public static List getReferenceFilePaths(final FileSystem fs, final Path familyDir) throws IOException { List fds = listStatusWithStatusFilter(fs, familyDir, new ReferenceFileFilter(fs)); if (fds == null) { - return new ArrayList<>(); + return Collections.emptyList(); } List referenceFiles = new ArrayList<>(fds.size()); for (FileStatus fdfs: fds) { diff --git a/hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift/ThriftServerRunner.java b/hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift/ThriftServerRunner.java index 0060181..7ee292e 100644 --- a/hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift/ThriftServerRunner.java +++ b/hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift/ThriftServerRunner.java @@ -1514,7 +1514,7 @@ public class ThriftServerRunner implements Runnable { try { results = resultScannerWrapper.getScanner().next(nbRows); if (null == results) { - return new ArrayList<>(); + return Collections.emptyList(); } } catch (IOException e) { LOG.warn(e.getMessage(), e);