Package org.apache.hadoop.hbase.constraint

Class Constraints

java.lang.Object

org.apache.hadoop.hbase.constraint.Constraints

@Public
public final class Constraints
extends Object

Utilities for adding/removing constraints from a table.

Since TableDescriptor is immutable now, you should use TableDescriptorBuilder. And when disabling or removing constraints, you could use TableDescriptorBuilder.newBuilder(TableDescriptor) to clone the old TableDescriptor and then pass it the below methods.

Field Summary

Fields

Modifier and Type	Field	Description
private static final Pattern	CONSTRAINT_HTD_ATTR_KEY_PATTERN
private static final String	CONSTRAINT_HTD_KEY_PREFIX
private static final Comparator<Constraint>	constraintComparator
private static String	COUNTER_KEY
private static final int	DEFAULT_PRIORITY
private static final String	ENABLED_KEY
private static final org.slf4j.Logger	LOG
private static final long	MIN_PRIORITY
private static final String	PRIORITY_KEY
private static final long	UNSET_PRIORITY

Constructor Summary

Constructors

Modifier	Constructor	Description
private	Constraints()

Method Summary

Modifier and Type	Method	Description
static TableDescriptorBuilder	add(TableDescriptorBuilder builder, Class<? extends Constraint>... constraints)	Add configuration-less constraints to the table.
static TableDescriptorBuilder	add(TableDescriptorBuilder builder, Class<? extends Constraint> constraint, org.apache.hadoop.conf.Configuration conf)	Add a Constraint to the table with the given configuration
static TableDescriptorBuilder	add(TableDescriptorBuilder builder, Pair<Class<? extends Constraint>,org.apache.hadoop.conf.Configuration>... constraints)	Add constraints and their associated configurations to the table.
private static TableDescriptorBuilder	addConstraint(TableDescriptorBuilder builder, Class<? extends Constraint> clazz, org.apache.hadoop.conf.Configuration conf, long priority)	Write the raw constraint and configuration to the descriptor.
private static TableDescriptorBuilder	changeConstraintEnabled(TableDescriptorBuilder builder, Class<? extends Constraint> clazz, boolean enabled)	Change the whether the constraint (if it is already present) is enabled or disabled.
private static org.apache.hadoop.conf.Configuration	configure(org.apache.hadoop.conf.Configuration conf, boolean enabled, long priority)	Setup the configuration for a constraint as to whether it is enabled and its priority
static TableDescriptorBuilder	disable(TableDescriptorBuilder builder)	Turn off processing constraints for a given table, even if constraints have been turned on or added.
static void	disableConstraint(TableDescriptorBuilder builder, Class<? extends Constraint> clazz)	Disable the given Constraint.
static TableDescriptorBuilder	enable(TableDescriptorBuilder builder)	Enable constraints on a table.
static void	enableConstraint(TableDescriptorBuilder builder, Class<? extends Constraint> clazz)	Enable the given Constraint.
static boolean	enabled(TableDescriptor desc, Class<? extends Constraint> clazz)	Check to see if the given constraint is enabled.
(package private) static List<? extends Constraint>	getConstraints(TableDescriptor desc, ClassLoader classloader)	Get the constraints stored in the table descriptor
private static Pair<String,String>	getKeyValueForClass(TableDescriptorBuilder builder, Class<? extends Constraint> clazz)	Get the kv Map.Entry in the descriptor builder for the specified class
private static Pair<String,String>	getKeyValueForClass(TableDescriptor desc, Class<? extends Constraint> clazz)	Get the kv Map.Entry in the descriptor for the specified class
private static long	getNextPriority(TableDescriptorBuilder builder)
static boolean	has(TableDescriptor desc, Class<? extends Constraint> clazz)	Check to see if the Constraint is currently set.
private static org.apache.hadoop.conf.Configuration	readConfiguration(byte[] bytes)	Read the Configuration stored in the byte stream.
private static org.apache.hadoop.conf.Configuration	readConfiguration(String bytes)	Read in the configuration from the String encoded configuration
static TableDescriptorBuilder	remove(TableDescriptorBuilder builder)	Remove all Constraints that have been added to the table and turn off the constraint processing.
static TableDescriptorBuilder	remove(TableDescriptorBuilder builder, Class<? extends Constraint> clazz)	Remove the constraint (and associated information) for the table descriptor.
private static String	serializeConfiguration(org.apache.hadoop.conf.Configuration conf)	Write the configuration to a String
private static String	serializeConstraintClass(Class<? extends Constraint> clazz)	Just write the class to a String representation of the class as a key for the TableDescriptor
static TableDescriptorBuilder	setConfiguration(TableDescriptorBuilder builder, Class<? extends Constraint> clazz, org.apache.hadoop.conf.Configuration configuration)	Update the configuration for the Constraint; does not change the order in which the constraint is run.
private static TableDescriptorBuilder	updateLatestPriority(TableDescriptorBuilder builder, long priority)
private static TableDescriptorBuilder	writeConstraint(TableDescriptorBuilder builder, String key, org.apache.hadoop.conf.Configuration conf)	Write the given key and associated configuration to the TableDescriptorBuilder.

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_PRIORITY

private static final int DEFAULT_PRIORITY

See Also:

• Constant Field Values

LOG

private static final org.slf4j.Logger LOG

CONSTRAINT_HTD_KEY_PREFIX

private static final String CONSTRAINT_HTD_KEY_PREFIX

See Also:

• Constant Field Values

CONSTRAINT_HTD_ATTR_KEY_PATTERN

private static final Pattern CONSTRAINT_HTD_ATTR_KEY_PATTERN

ENABLED_KEY

private static final String ENABLED_KEY

See Also:

• Constant Field Values

PRIORITY_KEY

private static final String PRIORITY_KEY

See Also:

• Constant Field Values

MIN_PRIORITY

private static final long MIN_PRIORITY

See Also:

• Constant Field Values

UNSET_PRIORITY

private static final long UNSET_PRIORITY

See Also:

• Constant Field Values

COUNTER_KEY

private static String COUNTER_KEY

constraintComparator

private static final Comparator<Constraint> constraintComparator

Constructor Details

Constraints

private Constraints()

Method Details

enable

public static TableDescriptorBuilder enable(TableDescriptorBuilder builder)
                                     throws IOException

Enable constraints on a table.

Currently, if you attempt to add a constraint to the table, then Constraints will automatically be turned on.

Throws:

IOException

disable

public static TableDescriptorBuilder disable(TableDescriptorBuilder builder)
                                      throws IOException

Turn off processing constraints for a given table, even if constraints have been turned on or added.

Throws:

IOException

remove

public static TableDescriptorBuilder remove(TableDescriptorBuilder builder)
                                     throws IOException

Remove all Constraints that have been added to the table and turn off the constraint processing.

All Configurations and their associated Constraint are removed.

Throws:

IOException

has

public static boolean has(TableDescriptor desc,
 Class<? extends Constraint> clazz)

Check to see if the Constraint is currently set.

Parameters:

desc - TableDescriptor to check

clazz - Constraint class to check for.

Returns:

true if the Constraint is present, even if it is disabled. false otherwise.

getKeyValueForClass

private static Pair<String,String> getKeyValueForClass(TableDescriptor desc,
 Class<? extends Constraint> clazz)

Get the kv Map.Entry in the descriptor for the specified class

Parameters:

desc - TableDescriptor to read

clazz - To search for

Returns:

The Pair of <key, value> in the table, if that class is present. null otherwise.

getKeyValueForClass

private static Pair<String,String> getKeyValueForClass(TableDescriptorBuilder builder,
 Class<? extends Constraint> clazz)

Get the kv Map.Entry in the descriptor builder for the specified class

Parameters:

builder - TableDescriptorBuilder to read

clazz - To search for

Returns:

The Pair of <key, value> in the table, if that class is present. null otherwise.

add

@SafeVarargs
public static TableDescriptorBuilder add(TableDescriptorBuilder builder,
 Class<? extends Constraint>... constraints)
                                  throws IOException

Add configuration-less constraints to the table.

This will overwrite any configuration associated with the previous constraint of the same class.

Each constraint, when added to the table, will have a specific priority, dictating the order in which the Constraint will be run. A Constraint earlier in the list will be run before those later in the list. The same logic applies between two Constraints over time (earlier added is run first on the regionserver).

Parameters:

builder - TableDescriptorBuilder to add a Constraint

constraints - Constraints to add. All constraints are considered automatically enabled on add

Throws:

IOException - If constraint could not be serialized/added to table

add

@SafeVarargs
public static TableDescriptorBuilder add(TableDescriptorBuilder builder,
 Pair<Class<? extends Constraint>,org.apache.hadoop.conf.Configuration>... constraints)
                                  throws IOException

Add constraints and their associated configurations to the table.

Adding the same constraint class twice will overwrite the first constraint's configuration

Each constraint, when added to the table, will have a specific priority, dictating the order in which the Constraint will be run. A Constraint earlier in the list will be run before those later in the list. The same logic applies between two Constraints over time (earlier added is run first on the regionserver).

Parameters:

builder - TableDescriptorBuilder to add a Constraint

constraints - Pair of a Constraint and its associated Configuration. The Constraint will be configured on load with the specified configuration.All constraints are considered automatically enabled on add

Throws:

IOException - if any constraint could not be deserialized. Assumes if 1 constraint is not loaded properly, something has gone terribly wrong and that all constraints need to be enforced.

add

public static TableDescriptorBuilder add(TableDescriptorBuilder builder,
 Class<? extends Constraint> constraint,
 org.apache.hadoop.conf.Configuration conf)
                                  throws IOException

Add a Constraint to the table with the given configuration

Each constraint, when added to the table, will have a specific priority, dictating the order in which the Constraint will be run. A Constraint added will run on the regionserver before those added to the TableDescriptorBuilder later.

Parameters:

builder - TableDescriptorBuilder to add a Constraint

constraint - to be added

conf - configuration associated with the constraint

Throws:

IOException - if any constraint could not be deserialized. Assumes if 1 constraint is not loaded properly, something has gone terribly wrong and that all constraints need to be enforced.

addConstraint

private static TableDescriptorBuilder addConstraint(TableDescriptorBuilder builder,
 Class<? extends Constraint> clazz,
 org.apache.hadoop.conf.Configuration conf,
 long priority)
                                             throws IOException

Write the raw constraint and configuration to the descriptor.

This method takes care of creating a new configuration based on the passed in configuration and then updating that with enabled and priority of the constraint.

When a constraint is added, it is automatically enabled.

Throws:

IOException

configure

private static org.apache.hadoop.conf.Configuration configure(org.apache.hadoop.conf.Configuration conf,
 boolean enabled,
 long priority)

Setup the configuration for a constraint as to whether it is enabled and its priority

Parameters:

conf - on which to base the new configuration

enabled - true if it should be run

priority - relative to other constraints

Returns:

a new configuration, storable in the TableDescriptor

serializeConstraintClass

private static String serializeConstraintClass(Class<? extends Constraint> clazz)

Just write the class to a String representation of the class as a key for the TableDescriptor

Parameters:

clazz - Constraint class to convert to a TableDescriptor key

Returns:

key to store in the TableDescriptor

writeConstraint

private static TableDescriptorBuilder writeConstraint(TableDescriptorBuilder builder,
 String key,
 org.apache.hadoop.conf.Configuration conf)
                                               throws IOException

Write the given key and associated configuration to the TableDescriptorBuilder.

Throws:

IOException

serializeConfiguration

private static String serializeConfiguration(org.apache.hadoop.conf.Configuration conf)
                                      throws IOException

Write the configuration to a String

Parameters:

conf - to write

Returns:

String representation of that configuration

Throws:

IOException

readConfiguration

private static org.apache.hadoop.conf.Configuration readConfiguration(byte[] bytes)
                                                               throws IOException

Read the Configuration stored in the byte stream.

Parameters:

bytes - to read from

Returns:

A valid configuration

Throws:

IOException

readConfiguration

private static org.apache.hadoop.conf.Configuration readConfiguration(String bytes)
                                                               throws IOException

Read in the configuration from the String encoded configuration

Parameters:

bytes - to read from

Returns:

A valid configuration

Throws:

IOException - if the configuration could not be read

getNextPriority

private static long getNextPriority(TableDescriptorBuilder builder)

updateLatestPriority

private static TableDescriptorBuilder updateLatestPriority(TableDescriptorBuilder builder,
 long priority)

setConfiguration

public static TableDescriptorBuilder setConfiguration(TableDescriptorBuilder builder,
 Class<? extends Constraint> clazz,
 org.apache.hadoop.conf.Configuration configuration)
                                               throws IOException,
IllegalArgumentException

Update the configuration for the Constraint; does not change the order in which the constraint is run.

Parameters:

builder - TableDescriptorBuilder to update

clazz - Constraint to update

configuration - to update the Constraint with.

Throws:

IOException - if the Constraint was not stored correctly

IllegalArgumentException - if the Constraint was not present on this table.

remove

public static TableDescriptorBuilder remove(TableDescriptorBuilder builder,
 Class<? extends Constraint> clazz)

Remove the constraint (and associated information) for the table descriptor.

Parameters:

builder - TableDescriptorBuilder to modify

clazz - Constraint class to remove

enableConstraint

public static void enableConstraint(TableDescriptorBuilder builder,
 Class<? extends Constraint> clazz)
                             throws IOException

Enable the given Constraint. Retains all the information (e.g. Configuration) for the Constraint, but makes sure that it gets loaded on the table.

Parameters:

builder - TableDescriptorBuilder to modify

clazz - Constraint to enable

Throws:

IOException - If the constraint cannot be properly deserialized

disableConstraint

public static void disableConstraint(TableDescriptorBuilder builder,
 Class<? extends Constraint> clazz)
                              throws IOException

Disable the given Constraint. Retains all the information (e.g. Configuration) for the Constraint, but it just doesn't load the Constraint on the table.

Parameters:

builder - TableDescriptorBuilder to modify

clazz - Constraint to disable.

Throws:

IOException - if the constraint cannot be found

changeConstraintEnabled

private static TableDescriptorBuilder changeConstraintEnabled(TableDescriptorBuilder builder,
 Class<? extends Constraint> clazz,
 boolean enabled)
                                                       throws IOException

Change the whether the constraint (if it is already present) is enabled or disabled.

Throws:

IOException

enabled

public static boolean enabled(TableDescriptor desc,
 Class<? extends Constraint> clazz)
                       throws IOException

Check to see if the given constraint is enabled.

Parameters:

desc - TableDescriptor to check.

clazz - Constraint to check for

Returns:

true if the Constraint is present and enabled. false otherwise.

Throws:

IOException - If the constraint has improperly stored in the table

getConstraints

static List<? extends Constraint> getConstraints(TableDescriptor desc,
 ClassLoader classloader)
                                          throws IOException

Get the constraints stored in the table descriptor

Parameters:

desc - To read from

classloader - To use when loading classes. If a special classloader is used on a region, for instance, then that should be the classloader used to load the constraints. This could also apply to unit-testing situation, where want to ensure that class is reloaded or not.

Returns:

List of configured Constraints

Throws:

IOException - if any part of reading/arguments fails