Introduce ReadOptimizedView & RealtimeView out of TableFileSystemView

- Usage now marks code as clearly using either RO or RT views, for future evolution
  - Tests on all of FileGroups and FileSlices

hoodie-client/src/main/java/com/uber/hoodie/HoodieReadClient.java

@@ -177,7 +177,7 @@ public class HoodieReadClient implements Serializable {
                             + hoodieTable.getMetaClient().getBasePath());
                 }
 
-                TableFileSystemView fileSystemView = new HoodieTableFileSystemView(hoodieTable.getMetaClient(),
+                TableFileSystemView.ReadOptimizedView fileSystemView = new HoodieTableFileSystemView(hoodieTable.getMetaClient(),
                         hoodieTable.getCompletedCommitTimeline(), fs.globStatus(new Path(path)));
                 List<HoodieDataFile> latestFiles = fileSystemView.getLatestDataFiles().collect(
                         Collectors.toList());

hoodie-client/src/main/java/com/uber/hoodie/HoodieWriteClient.java

@@ -479,7 +479,7 @@ public class HoodieWriteClient<T extends HoodieRecordPayload> implements Seriali
                 .mapToPair((PairFunction<String, String, List<String>>) partitionPath -> {
                     // Scan all partitions files with this commit time
                     logger.info("Collecting latest files in partition path " + partitionPath);
-                    TableFileSystemView view = table.getFileSystemView();
+                    TableFileSystemView.ReadOptimizedView view = table.getROFileSystemView();
                     List<String> latestFiles =
                         view.getLatestDataFilesBeforeOrOn(partitionPath, commitTime)
                             .map(HoodieDataFile::getFileName).collect(Collectors.toList());

hoodie-client/src/main/java/com/uber/hoodie/index/HoodieBloomIndex.java

@@ -184,7 +184,7 @@ public class HoodieBloomIndex<T extends HoodieRecordPayload> extends HoodieIndex
                     List<Tuple2<String, String>> list = new ArrayList<>();
                     if (latestCommitTime.isPresent()) {
                         List<HoodieDataFile> filteredFiles =
-                                hoodieTable.getFileSystemView().getLatestDataFilesBeforeOrOn(partitionPath,
+                                hoodieTable.getROFileSystemView().getLatestDataFilesBeforeOrOn(partitionPath,
                                         latestCommitTime.get().getTimestamp()).collect(Collectors.toList());
                         for (HoodieDataFile file : filteredFiles) {
                             list.add(new Tuple2<>(partitionPath, file.getFileName()));

hoodie-client/src/main/java/com/uber/hoodie/io/HoodieIOHandle.java

@@ -40,7 +40,7 @@ public abstract class HoodieIOHandle<T extends HoodieRecordPayload> {
     protected final FileSystem fs;
     protected final HoodieTable<T> hoodieTable;
     protected HoodieTimeline hoodieTimeline;
-    protected TableFileSystemView fileSystemView;
+    protected TableFileSystemView.ReadOptimizedView fileSystemView;
     protected final Schema schema;
 
     public HoodieIOHandle(HoodieWriteConfig config, String commitTime,
@@ -50,7 +50,7 @@ public abstract class HoodieIOHandle<T extends HoodieRecordPayload> {
         this.fs = FSUtils.getFs();
         this.hoodieTable = hoodieTable;
         this.hoodieTimeline = hoodieTable.getCompletedCommitTimeline();
-        this.fileSystemView = hoodieTable.getFileSystemView();
+        this.fileSystemView = hoodieTable.getROFileSystemView();
         this.schema =
             HoodieAvroUtils.addMetadataFields(new Schema.Parser().parse(config.getSchema()));
     }

hoodie-client/src/main/java/com/uber/hoodie/io/compact/HoodieRealtimeTableCompactor.java

@@ -84,7 +84,7 @@ public class HoodieRealtimeTableCompactor implements HoodieCompactor {
     List<CompactionOperation> operations =
         jsc.parallelize(partitionPaths, partitionPaths.size())
             .flatMap((FlatMapFunction<String, CompactionOperation>) partitionPath -> hoodieTable
-                .getFileSystemView()
+                .getRTFileSystemView()
                 .getLatestFileSlices(partitionPath)
                 .map(s -> new CompactionOperation(s.getDataFile().get(),
                         partitionPath, s.getLogFiles().collect(Collectors.toList()), config))

hoodie-client/src/main/java/com/uber/hoodie/table/HoodieCopyOnWriteTable.java

@@ -311,7 +311,7 @@ public class HoodieCopyOnWriteTable<T extends HoodieRecordPayload> extends Hoodi
 
             if (!commitTimeline.empty()) { // if we have some commits
                 HoodieInstant latestCommitTime = commitTimeline.lastInstant().get();
-                List<HoodieDataFile> allFiles = getFileSystemView()
+                List<HoodieDataFile> allFiles = getROFileSystemView()
                     .getLatestDataFilesBeforeOrOn(partitionPath, latestCommitTime.getTimestamp())
                     .collect(Collectors.toList());
 

hoodie-client/src/main/java/com/uber/hoodie/table/HoodieTable.java

@@ -108,6 +108,24 @@ public abstract class HoodieTable<T extends HoodieRecordPayload> implements Seri
         return new HoodieTableFileSystemView(metaClient, getCompletedCommitTimeline());
     }
 
+    /**
+     * Get the read optimized view of the file system for this table
+     *
+     * @return
+     */
+    public TableFileSystemView.ReadOptimizedView getROFileSystemView() {
+        return new HoodieTableFileSystemView(metaClient, getCompletedCommitTimeline());
+    }
+
+    /**
+     * Get the real time view of the file system for this table
+     *
+     * @return
+     */
+    public TableFileSystemView.RealtimeView getRTFileSystemView() {
+        return new HoodieTableFileSystemView(metaClient, getCompletedCommitTimeline());
+    }
+
     /**
      * Get the view of the file system for this table
      *