BlockAliasMap.Reader (Apache Hadoop HDFS 3.5.0 API)
Description: declaration: package: org.apache.hadoop.hdfs.server.common.blockaliasmap, class: BlockAliasMap, class: Reader

Package org.apache.hadoop.hdfs.server.common.blockaliasmap

# Class BlockAliasMap.Reader<U extends BlockAlias>

java.lang.Object
org.apache.hadoop.hdfs.server.common.blockaliasmap.BlockAliasMap.Reader<U>

All Implemented Interfaces:
  `Closeable`, `AutoCloseable`, `Iterable<U>`

Direct Known Subclasses:
  `LevelDBFileRegionAliasMap.LevelDBReader`, `TextFileRegionAliasMap.TextReader`

Enclosing class:
  BlockAliasMap<T extends BlockAlias>

public abstract static class BlockAliasMap.Reader<U extends BlockAlias> extends Object implements Iterable<U>, Closeable
An abstract class that is used to read `BlockAlias`es for provided blocks.

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `static interface`
  `BlockAliasMap.Reader.Options`
  reader options.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Reader()`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `abstract Optional<U>`
  `resolve(org.apache.hadoop.hdfs.protocol.Block ident)`

  ### Methods inherited from class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

  ### Methods inherited from interface java.io.Closeable

  `close`

  ### Methods inherited from interface java.lang.Iterable

  `forEach, iterator, spliterator`

- ## Constructor Details

  - ### Reader

    public Reader()

- ## Method Details

  - ### resolve

    public abstract Optional<U> resolve(org.apache.hadoop.hdfs.protocol.Block ident) throws IOException
    Parameters:
      `ident` - block to resolve
    Returns:
      BlockAlias corresponding to the provided block.
    Throws:
      `IOException`