Package org.apache.hadoop.hbase

Class TableName

java.lang.Object

org.apache.hadoop.hbase.TableName

All Implemented Interfaces:

Comparable<TableName>

@Public
public final class TableName
extends Object
implements Comparable<TableName>

Immutable POJO class for representing a table name. Which is of the form: <table namespace>:<table qualifier> Two special namespaces: 1. hbase - system namespace, used to contain hbase internal tables 2. default - tables with no explicit specified namespace will automatically fall into this namespace. ie a) foo:bar, means namespace=foo and qualifier=bar b) bar, means namespace=default and qualifier=bar c) default:bar, means namespace=default and qualifier=bar

Internally, in this class, we cache the instances to limit the number of objects and make the "equals" faster. We try to minimize the number of objects created of the number of array copy to check if we already have an instance of this TableName. The code is not optimize for a new instance creation but is optimized to check for existence.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DISALLOWED_TABLE_NAME	One globally disallowed name
private final int	hashCode
static final TableName	META_TABLE_NAME	The hbase:meta table's name.
private final byte[]	name
private final String	nameAsString
private final byte[]	namespace
static final char	NAMESPACE_DELIM	Namespace delimiter
static final TableName	NAMESPACE_TABLE_NAME	The Namespace table's name.
private final String	namespaceAsString
static final String	OLD_META_STR
static final TableName	OLD_META_TABLE_NAME	TableName for old .META.
static final String	OLD_ROOT_STR
static final TableName	OLD_ROOT_TABLE_NAME	TableName for old -ROOT- table.
private final byte[]	qualifier
private final String	qualifierAsString
private final boolean	systemTable
private static final Set<TableName>	tableCache	See createTableNameIfNecessary(ByteBuffer, ByteBuffer)
static final String	VALID_NAMESPACE_REGEX
static final String	VALID_TABLE_QUALIFIER_REGEX
static final String	VALID_USER_TABLE_REGEX

Constructor Summary

Constructors

Modifier	Constructor	Description
private	TableName(String qualifier)	This is only for the old and meta tables.
private	TableName(ByteBuffer namespace, ByteBuffer qualifier)

Method Summary

Modifier and Type	Method	Description
int	compareTo(TableName tableName)
private static TableName	createTableNameIfNecessary(ByteBuffer bns, ByteBuffer qns)	Check that the object does not exist already.
boolean	equals(Object o)
private static TableName	getADummyTableName(String qualifier)	It is used to create table names for old META, and ROOT table.
byte[]	getName()
String	getNameAsString()
byte[]	getNamespace()
String	getNamespaceAsString()
String	getNameWithNamespaceInclAsString()	Ideally, getNameAsString should contain namespace within it, but if the namespace is default, it just returns the name.
byte[]	getQualifier()
String	getQualifierAsString()
int	hashCode()
static byte[]	isLegalFullyQualifiedTableName(byte[] tableName)	Check passed byte array, "tableName", is legal user-space table name.
static void	isLegalNamespaceName(byte[] namespaceName)
static void	isLegalNamespaceName(byte[] namespaceName, int start, int end)	Valid namespace characters are alphabetic characters, numbers, and underscores.
static byte[]	isLegalTableQualifierName(byte[] qualifierName)
static byte[]	isLegalTableQualifierName(byte[] qualifierName, boolean isSnapshot)
static void	isLegalTableQualifierName(byte[] qualifierName, int start, int end)	Qualifier names can only contain 'word' characters [\p{IsAlphabetic}\p{Digit}] or '_', '.' or '-'.
static void	isLegalTableQualifierName(byte[] qualifierName, int start, int end, boolean isSnapshot)
static boolean	isMetaTableName(TableName tn)	Returns True if tn is the hbase:meta table name.
boolean	isSystemTable()
byte[]	toBytes()	Returns A pointer to TableName as String bytes.
String	toString()
static TableName	valueOf(byte[] fullName)	Construct a TableName
static TableName	valueOf(byte[] namespace, byte[] qualifier)
static TableName	valueOf(byte[] fullName, int offset, int length)	Construct a TableName
static TableName	valueOf(String name)	Construct a TableName
static TableName	valueOf(String namespaceAsString, String qualifierAsString)
static TableName	valueOf(ByteBuffer fullname)	Construct a TableName
static TableName	valueOf(ByteBuffer namespace, ByteBuffer qualifier)

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

tableCache

private static final Set<TableName> tableCache

See createTableNameIfNecessary(ByteBuffer, ByteBuffer)

NAMESPACE_DELIM

public static final char NAMESPACE_DELIM

Namespace delimiter

See Also:

• Constant Field Values

VALID_NAMESPACE_REGEX

public static final String VALID_NAMESPACE_REGEX

See Also:

• Constant Field Values

VALID_TABLE_QUALIFIER_REGEX

public static final String VALID_TABLE_QUALIFIER_REGEX

See Also:

• Constant Field Values

VALID_USER_TABLE_REGEX

public static final String VALID_USER_TABLE_REGEX

See Also:

• Constant Field Values

META_TABLE_NAME

public static final TableName META_TABLE_NAME

The hbase:meta table's name.

NAMESPACE_TABLE_NAME

public static final TableName NAMESPACE_TABLE_NAME

The Namespace table's name.

OLD_META_STR

public static final String OLD_META_STR

See Also:

• Constant Field Values

OLD_ROOT_STR

public static final String OLD_ROOT_STR

See Also:

• Constant Field Values

DISALLOWED_TABLE_NAME

public static final String DISALLOWED_TABLE_NAME

One globally disallowed name

See Also:

• Constant Field Values

OLD_ROOT_TABLE_NAME

public static final TableName OLD_ROOT_TABLE_NAME

TableName for old -ROOT- table. It is used to read/process old WALs which have ROOT edits.

OLD_META_TABLE_NAME

public static final TableName OLD_META_TABLE_NAME

TableName for old .META. table. Used in testing.

name

private final byte[] name

nameAsString

private final String nameAsString

namespace

private final byte[] namespace

namespaceAsString

private final String namespaceAsString

qualifier

private final byte[] qualifier

qualifierAsString

private final String qualifierAsString

systemTable

private final boolean systemTable

hashCode

private final int hashCode

Constructor Details

TableName

private TableName(ByteBuffer namespace,
 ByteBuffer qualifier)
           throws IllegalArgumentException

Throws:

IllegalArgumentException

TableName

private TableName(String qualifier)

This is only for the old and meta tables.

Method Details

isMetaTableName

public static boolean isMetaTableName(TableName tn)

Returns True if tn is the hbase:meta table name.

isLegalFullyQualifiedTableName

public static byte[] isLegalFullyQualifiedTableName(byte[] tableName)

Check passed byte array, "tableName", is legal user-space table name.

Returns:

Returns passed tableName param

Throws:

IllegalArgumentException - if passed a tableName is null or is made of other than 'word' characters or underscores: i.e. [\p{IsAlphabetic}\p{Digit}.-:]. The ':' is used to delimit the namespace from the table name and can be used for nothing else. Namespace names can only contain 'word' characters [\p{IsAlphabetic}\p{Digit}] or '_' Qualifier names can only contain 'word' characters [\p{IsAlphabetic}\p{Digit}] or '_', '.' or '-'. The name may not start with '.' or '-'. Valid fully qualified table names: foo:bar, namespace=>foo, table=>bar org:foo.bar, namespace=org, table=>foo.bar

isLegalTableQualifierName

public static byte[] isLegalTableQualifierName(byte[] qualifierName)

isLegalTableQualifierName

public static byte[] isLegalTableQualifierName(byte[] qualifierName,
 boolean isSnapshot)

isLegalTableQualifierName

public static void isLegalTableQualifierName(byte[] qualifierName,
 int start,
 int end)

Qualifier names can only contain 'word' characters [\p{IsAlphabetic}\p{Digit}] or '_', '.' or '-'. The name may not start with '.' or '-'.

Parameters:

qualifierName - byte array containing the qualifier name

start - start index

end - end index (exclusive)

isLegalTableQualifierName

public static void isLegalTableQualifierName(byte[] qualifierName,
 int start,
 int end,
 boolean isSnapshot)

isLegalNamespaceName

public static void isLegalNamespaceName(byte[] namespaceName)

isLegalNamespaceName

public static void isLegalNamespaceName(byte[] namespaceName,
 int start,
 int end)

Valid namespace characters are alphabetic characters, numbers, and underscores.

getName

public byte[] getName()

getNameAsString

public String getNameAsString()

getNamespace

public byte[] getNamespace()

getNamespaceAsString

public String getNamespaceAsString()

getNameWithNamespaceInclAsString

public String getNameWithNamespaceInclAsString()

Ideally, getNameAsString should contain namespace within it, but if the namespace is default, it just returns the name. This method takes care of this corner case.

getQualifier

public byte[] getQualifier()

getQualifierAsString

public String getQualifierAsString()

toBytes

public byte[] toBytes()

Returns A pointer to TableName as String bytes.

isSystemTable

public boolean isSystemTable()

toString

public String toString()

Overrides:

toString in class Object

createTableNameIfNecessary

private static TableName createTableNameIfNecessary(ByteBuffer bns,
 ByteBuffer qns)

Check that the object does not exist already. There are two reasons for creating the objects only once: 1) With 100K regions, the table names take ~20MB. 2) Equals becomes much faster as it's resolved with a reference and an int comparison.

getADummyTableName

private static TableName getADummyTableName(String qualifier)

It is used to create table names for old META, and ROOT table. These tables are not really legal tables. They are not added into the cache.

Returns:

a dummy TableName instance (with no validation) for the passed qualifier

valueOf

public static TableName valueOf(String namespaceAsString,
 String qualifierAsString)

valueOf

public static TableName valueOf(byte[] fullName)
                         throws IllegalArgumentException

Construct a TableName

Parameters:

fullName - will use the entire byte array

Throws:

IllegalArgumentException - if fullName equals old root or old meta. Some code depends on this. The test is buried in the table creation to save on array comparison when we're creating a standard table object that will be in the cache.

valueOf

public static TableName valueOf(byte[] fullName,
 int offset,
 int length)
                         throws IllegalArgumentException

Construct a TableName

Parameters:

fullName - byte array to look into

offset - within said array

length - within said array

Throws:

IllegalArgumentException - if fullName equals old root or old meta.

valueOf

public static TableName valueOf(ByteBuffer fullname)

Construct a TableName

Parameters:

fullname - of a table, possibly with a leading namespace and ':' as delimiter.

Throws:

IllegalArgumentException - if fullName equals old root or old meta.

valueOf

public static TableName valueOf(String name)

Construct a TableName

Throws:

IllegalArgumentException - if fullName equals old root or old meta. Some code depends on this.

valueOf

public static TableName valueOf(byte[] namespace,
 byte[] qualifier)

valueOf

public static TableName valueOf(ByteBuffer namespace,
 ByteBuffer qualifier)

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

compareTo

public int compareTo(TableName tableName)

Specified by:

compareTo in interface Comparable<TableName>