org.apache.hadoop.hbase

Interface TableDescriptors

All Superinterfaces:

AutoCloseable, Closeable

All Known Implementing Classes:

FSTableDescriptors

@InterfaceAudience.Private
public interface TableDescriptors
extends Closeable

Get, remove and modify table descriptors.

Method Summary

Modifier and Type	Method and Description
default void	close()
default boolean	exists(TableName tableName) Test whether a given table exists, i.e, has a table descriptor.
TableDescriptor	get(TableName tableName)
Map<String,TableDescriptor>	getAll() Get Map of all TableDescriptors.
Map<String,TableDescriptor>	getByNamespace(String name) Get Map of all NamespaceDescriptors for a given namespace.
TableDescriptor	remove(TableName tablename)
default void	update(TableDescriptor htd) Add or update descriptor.
void	update(TableDescriptor htd, boolean cacheOnly) Add or update descriptor

Method Detail

exists

default boolean exists(TableName tableName)
                throws IOException

Test whether a given table exists, i.e, has a table descriptor.

Throws:

IOException

close

default void close()
            throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException

get

TableDescriptor get(TableName tableName)
             throws IOException

Returns:

TableDescriptor for tablename

Throws:

IOException

getByNamespace

Map<String,TableDescriptor> getByNamespace(String name)
                                    throws IOException

Get Map of all NamespaceDescriptors for a given namespace.

Returns:

Map of all descriptors.

Throws:

IOException

getAll

Map<String,TableDescriptor> getAll()
                            throws IOException

Get Map of all TableDescriptors. Populates the descriptor cache as a side effect.

Notice: the key of map is the table name which contains namespace. It was generated by TableName.getNameWithNamespaceInclAsString().

Returns:

Map of all descriptors.

Throws:

IOException

update

default void update(TableDescriptor htd)
             throws IOException

Add or update descriptor. Just call update(TableDescriptor, boolean) with cacheOnly as false.

Throws:

IOException

update

void update(TableDescriptor htd,
            boolean cacheOnly)
     throws IOException

Add or update descriptor

Parameters:

htd - Descriptor to set into TableDescriptors

cacheOnly - only add the given htd to cache, without updating the storage. For example, when creating table, we will write the descriptor to fs when creating the fs layout, so we do not need to update the fs again.

Throws:

IOException

remove

TableDescriptor remove(TableName tablename)
                throws IOException

Returns:

Instance of table descriptor or null if none found.

Throws:

IOException