org.apache.gora.store.impl

Class DataStoreBase<K,T extends PersistentBase>

java.lang.Object

org.apache.gora.store.impl.DataStoreBase<K,T>

All Implemented Interfaces:

Closeable, AutoCloseable, DataStore<K,T>, org.apache.hadoop.conf.Configurable, org.apache.hadoop.io.Writable

Direct Known Subclasses:

AccumuloStore, CassandraStore, FileBackedDataStoreBase, HBaseStore, MemStore, SolrStore

public abstract class DataStoreBase<K,T extends PersistentBase>
extends Object
implements DataStore<K,T>, org.apache.hadoop.conf.Configurable, org.apache.hadoop.io.Writable, Closeable

A Base class for Avro persistent DataStores.

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	autoCreateSchema
protected BeanFactory<K,T>	beanFactory
protected org.apache.hadoop.conf.Configuration	conf
protected org.apache.avro.specific.SpecificDatumReader<T>	datumReader
protected org.apache.avro.specific.SpecificDatumWriter<T>	datumWriter
protected Map<String,org.apache.avro.Schema.Field>	fieldMap A map of field names to Field objects containing schema's fields
protected Class<K>	keyClass
static org.slf4j.Logger	LOG
protected Class<T>	persistentClass
protected Properties	properties
protected org.apache.avro.Schema	schema The schema of the persistent class

Constructor Summary

Constructors

Constructor and Description
DataStoreBase()

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object obj)
T	get(K key) Returns the object corresponding to the given key fetching all the fields.
BeanFactory<K,T>	getBeanFactory() Returns the BeanFactory used by the DataStore
org.apache.hadoop.conf.Configuration	getConf()
protected String[]	getFields()
protected String[]	getFieldsToQuery(String[] fields) Checks whether the fields argument is null, and if so returns all the fields of the Persistent object, else returns the argument.
Class<K>	getKeyClass() Returns the class of the keys
protected org.apache.hadoop.conf.Configuration	getOrCreateConf()
Class<T>	getPersistentClass() Returns the class of the persistent objects
protected String	getSchemaName(String mappingSchemaName, Class<?> persistentClass) Returns the name of the schema to use for the persistent class.
void	initialize(Class<K> keyClass, Class<T> persistentClass, Properties properties) Initializes this DataStore.
K	newKey() Returns a new instance of the key object.
T	newPersistent() Returns a new instance of the managed persistent object.
void	readFields(DataInput in)
void	setBeanFactory(BeanFactory<K,T> beanFactory) Sets the BeanFactory to use by the DataStore.
void	setConf(org.apache.hadoop.conf.Configuration conf)
void	setKeyClass(Class<K> keyClass) Sets the class of the keys
void	setPersistentClass(Class<T> persistentClass) Sets the class of the persistent objects
void	truncateSchema() Deletes all the data associated with the schema, but keeps the schema (table or similar) intact.
void	write(DataOutput out)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.gora.store.DataStore

close, createSchema, delete, deleteByQuery, deleteSchema, execute, flush, get, getPartitions, getSchemaName, newQuery, put, schemaExists

Methods inherited from interface java.io.Closeable

close

Field Detail

beanFactory

protected BeanFactory<K,T extends PersistentBase> beanFactory

keyClass

protected Class<K> keyClass

persistentClass

protected Class<T extends PersistentBase> persistentClass

schema

protected org.apache.avro.Schema schema

The schema of the persistent class

fieldMap

protected Map<String,org.apache.avro.Schema.Field> fieldMap

A map of field names to Field objects containing schema's fields

conf

protected org.apache.hadoop.conf.Configuration conf

autoCreateSchema

protected boolean autoCreateSchema

properties

protected Properties properties

datumReader

protected org.apache.avro.specific.SpecificDatumReader<T extends PersistentBase> datumReader

datumWriter

protected org.apache.avro.specific.SpecificDatumWriter<T extends PersistentBase> datumWriter

LOG

public static final org.slf4j.Logger LOG

Constructor Detail

DataStoreBase

public DataStoreBase()

Method Detail

initialize

public void initialize(Class<K> keyClass,
              Class<T> persistentClass,
              Properties properties)

Description copied from interface: DataStore

Initializes this DataStore.

Specified by:

initialize in interface DataStore<K,T extends PersistentBase>

Parameters:

keyClass - the class of the keys

persistentClass - the class of the persistent objects

properties - extra metadata

setPersistentClass

public void setPersistentClass(Class<T> persistentClass)

Description copied from interface: DataStore

Sets the class of the persistent objects

Specified by:

setPersistentClass in interface DataStore<K,T extends PersistentBase>

Parameters:

persistentClass - class of persistent objects

getPersistentClass

public Class<T> getPersistentClass()

Description copied from interface: DataStore

Returns the class of the persistent objects

Specified by:

getPersistentClass in interface DataStore<K,T extends PersistentBase>

Returns:

class of the persistent objects

getKeyClass

public Class<K> getKeyClass()

Description copied from interface: DataStore

Returns the class of the keys

Specified by:

getKeyClass in interface DataStore<K,T extends PersistentBase>

Returns:

class of the keys

setKeyClass

public void setKeyClass(Class<K> keyClass)

Description copied from interface: DataStore

Sets the class of the keys

Specified by:

setKeyClass in interface DataStore<K,T extends PersistentBase>

Parameters:

keyClass - the class of keys

newKey

public K newKey()

Description copied from interface: DataStore

Returns a new instance of the key object. If the object cannot be instantiated (it the class is a Java primitive wrapper, or does not have no-arg constructor) it throws an exception. Only use this function if you can make sure that the key class has a no-arg constructor.

Specified by:

newKey in interface DataStore<K,T extends PersistentBase>

Returns:

a new instance of the key object.

newPersistent

public T newPersistent()

Description copied from interface: DataStore

Returns a new instance of the managed persistent object.

Specified by:

newPersistent in interface DataStore<K,T extends PersistentBase>

Returns:

a new instance of the managed persistent object.

setBeanFactory

public void setBeanFactory(BeanFactory<K,T> beanFactory)

Description copied from interface: DataStore

Sets the BeanFactory to use by the DataStore.

Specified by:

setBeanFactory in interface DataStore<K,T extends PersistentBase>

Parameters:

beanFactory - the BeanFactory to use

getBeanFactory

public BeanFactory<K,T> getBeanFactory()

Description copied from interface: DataStore

Returns the BeanFactory used by the DataStore

Specified by:

getBeanFactory in interface DataStore<K,T extends PersistentBase>

Returns:

the BeanFactory used by the DataStore

get

public T get(K key)

Description copied from interface: DataStore

Returns the object corresponding to the given key fetching all the fields.

Specified by:

get in interface DataStore<K,T extends PersistentBase>

Parameters:

key - the key of the object

Returns:

the Object corresponding to the key or null if it cannot be found

getFieldsToQuery

protected String[] getFieldsToQuery(String[] fields)

Checks whether the fields argument is null, and if so returns all the fields of the Persistent object, else returns the argument.

getFields

protected String[] getFields()

getConf

public org.apache.hadoop.conf.Configuration getConf()

Specified by:

getConf in interface org.apache.hadoop.conf.Configurable

setConf

public void setConf(org.apache.hadoop.conf.Configuration conf)

Specified by:

setConf in interface org.apache.hadoop.conf.Configurable

getOrCreateConf

protected org.apache.hadoop.conf.Configuration getOrCreateConf()

readFields

public void readFields(DataInput in)

Specified by:

readFields in interface org.apache.hadoop.io.Writable

write

public void write(DataOutput out)

Specified by:

write in interface org.apache.hadoop.io.Writable

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

truncateSchema

public void truncateSchema()

Description copied from interface: DataStore

Deletes all the data associated with the schema, but keeps the schema (table or similar) intact.

Specified by:

truncateSchema in interface DataStore<K,T extends PersistentBase>

getSchemaName

protected String getSchemaName(String mappingSchemaName,
                   Class<?> persistentClass)

Returns the name of the schema to use for the persistent class. First the schema name in the Configuration is used. If null, the schema name in the defined properties is returned. If null then the provided mappingSchemaName is returned. If this is null too, the class name, without the package, of the persistent class is returned.

Parameters:

mappingSchemaName - the name of the schema as read from the mapping file

persistentClass - persistent class