com.yahoo.elide.core

Class PersistentResource<T>

java.lang.Object

com.yahoo.elide.core.PersistentResource<T>

Type Parameters:

T - type of resource

All Implemented Interfaces:

PersistentResource<T>

public class PersistentResource<T>
extends Object
implements PersistentResource<T>

Resource wrapper around Entity bean.

Field Summary

Fields

Modifier and Type	Field and Description
static Set<String>	ALL_FIELDS
static String	CLASS_NO_FIELD
protected EntityDictionary	dictionary The Dictionary.
protected T	obj

Constructor Summary

Constructors

Constructor and Description
PersistentResource(T obj, PersistentResource parent, String parentRelationship, String id, @NonNull RequestScope scope) Construct a new resource from the ID provided.
PersistentResource(T obj, String id, @NonNull RequestScope scope) Construct a new resource from the ID provided.

Method Summary

Modifier and Type	Method and Description
protected void	addInverseRelation(String relationName, Object inverseObj) If a bidirectional relationship exists, attempts to add itself to the inverse relationship.
void	addRelation(String fieldName, PersistentResource newRelation) Add relation link from a given parent resource to a child resource.
protected boolean	addToCollection(Collection collection, String collectionName, PersistentResource toAdd) Adds a new element to a collection and tests update permission.
protected void	auditClass(Audit.Action action, ChangeSpec changeSpec) Audit an action on an entity.
protected void	auditField(ChangeSpec changeSpec) Audit an action on field.
protected static boolean	checkIncludeSparseField(Map<String,Set<String>> sparseFields, String type, String fieldName)
protected boolean	checkRelation(Relationship relationship) Check the permissions of the relationship, and return true or false.
protected void	checkTransferablePermission(Set<PersistentResource> resourceIdentifiers) Check if adding or updating a relation is allowed.
boolean	clearRelation(String relationName) Clear all elements from a relation.
static <T> PersistentResource<T>	createObject(PersistentResource<?> parent, String parentRelationship, Type<T> entityClass, RequestScope requestScope, Optional<String> uuid) Create a resource in the database.
static <T> PersistentResource<T>	createObject(Type<T> entityClass, RequestScope requestScope, Optional<String> uuid) Create a resource in the database.
protected void	deleteInverseRelation(String relationName, Object inverseEntity) If a bidirectional relationship exists, attempts to delete itself from the inverse relationship.
void	deleteResource() Delete an existing entity.
protected void	delFromCollection(Collection collection, String collectionName, PersistentResource toDelete, boolean isInverseCheck) Deletes an existing element in a collection and tests update and delete permissions.
boolean	equals(Object obj)
protected static io.reactivex.Observable<PersistentResource>	filter(Class<? extends Annotation> permission, Optional<FilterExpression> filter, Set<String> requestedFields, io.reactivex.Observable<PersistentResource> resources) Filter a set of PersistentResources.
protected Set<String>	filterFields(Collection<String> fields) Filter a set of fields.
static <T> T	firstOrNullIfEmpty(io.reactivex.Observable<T> coll)
Object	getAttribute(Attribute attr) Get the value for a particular attribute (i.e.
Object	getAttribute(String attr) Deprecated.
protected Map<String,Object>	getAttributes() Get attributes mapping from entity.
EntityDictionary	getDictionary() Gets dictionary.
String	getId() Get resource ID.
ResourceLineage	getLineage() Gets lineage.
T	getObject() Wrapped Entity bean.
io.reactivex.Observable<PersistentResource>	getRelation(List<String> ids, Relationship relationship) Load a relation from the PersistentResource.
PersistentResource	getRelation(Relationship relationship, String id) Get relation looking for a _single_ id.
io.reactivex.Observable<PersistentResource>	getRelationChecked(Relationship relationship) Get collection of resources from relation field.
io.reactivex.Observable<PersistentResource>	getRelationCheckedFiltered(Relationship relationship) Get observable of resources from relation field.
protected Map<String,Relationship>	getRelationships() Get relationship mappings.
protected Map<String,Relationship>	getRelationshipsWithRelationshipFunction(Function<String,io.reactivex.Observable<PersistentResource>> relationshipFunction) Get relationship mappings.
RelationshipType	getRelationshipType(String relation) Get a relationship type.
RequestScope	getRequestScope() Gets request scope.
Type<T>	getResourceType() Entity type.
String	getTypeName() Gets type.
Optional<String>	getUUID() Gets UUID.
static Object	getValue(Object target, String fieldName, RequestScope requestScope) Invoke the get[fieldName] method on the target object OR get the field with the corresponding name.
protected Object	getValueChecked(Attribute attribute) Gets a value from an entity and checks read permissions.
protected Object	getValueUnchecked(String fieldName) Retrieve an object without checking read permissions (i.e.
int	hashCode()
boolean	isIdGenerated() Indicates if the ID is generated or not.
boolean	isNewlyCreated() Returns whether or not this resource was created in this transaction.
static <T> @NonNull PersistentResource<T>	loadRecord(EntityProjection projection, String id, RequestScope requestScope) Load an single entity from the DB.
static io.reactivex.Observable<PersistentResource>	loadRecords(EntityProjection projection, List<String> ids, RequestScope requestScope) Load a collection from the datastore.
boolean	matchesId(String checkId) Check whether an id matches for this persistent resource.
protected void	nullValue(String fieldName, PersistentResource oldValue) Nulls the relationship or attribute and checks update permissions.
boolean	relationshipAlreadyExists(String fieldName, PersistentResource toAdd) Checks whether the new entity is already a part of the relationship.
void	removeRelation(String fieldName, PersistentResource removeResource) Remove a relationship.
void	setId(String id) Set resource ID.
void	setObject(T obj) Sets object.
protected void	setValue(String fieldName, Object value) Invoke the set[fieldName] method on the target object OR set the field with the corresponding name.
protected void	setValueChecked(String fieldName, Object newValue) Sets value.
Resource	toResource() Convert a persistent resource to a resource.
Resource	toResource(EntityProjection projection) Fetch a resource with support for lambda function for getting relationships and attributes.
Resource	toResource(Map<String,Relationship> relationships, Map<String,Object> attributes) Convert a persistent resource to a resource.
String	toString()
boolean	updateAttribute(String fieldName, Object newVal) Update attribute in existing resource.
boolean	updateRelation(String fieldName, Set<PersistentResource> resourceIdentifiers) Perform a full replacement on relationships.
protected boolean	updateToManyRelation(String fieldName, Set<PersistentResource> resourceIdentifiers, Set<PersistentResource> mine) Updates a to-many relationship.
protected boolean	updateToOneRelation(String fieldName, Set<PersistentResource> resourceIdentifiers, Set<PersistentResource> mine) Update a 2-one relationship.

Methods inherited from class java.lang.Object

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

Field Detail

obj

protected T obj

ALL_FIELDS

public static final Set<String> ALL_FIELDS

CLASS_NO_FIELD

public static final String CLASS_NO_FIELD

See Also:

Constant Field Values

dictionary

protected final EntityDictionary dictionary

The Dictionary.

Constructor Detail

PersistentResource

public PersistentResource(@NonNull
                          T obj,
                          PersistentResource parent,
                          String parentRelationship,
                          String id,
                          @NonNull
                          @NonNull RequestScope scope)

Construct a new resource from the ID provided.

Parameters:

obj - the obj

parent - the parent

id - the id

parentRelationship - The parent relationship traversed to this resource.

scope - the request scope

PersistentResource

public PersistentResource(@NonNull
                          T obj,
                          String id,
                          @NonNull
                          @NonNull RequestScope scope)

Construct a new resource from the ID provided.

Parameters:

obj - the obj

id - the id

scope - the request scope

Method Detail

toString

public String toString()

Overrides:

toString in class Object

createObject

public static <T> PersistentResource<T> createObject(Type<T> entityClass,
                                                     RequestScope requestScope,
                                                     Optional<String> uuid)

Create a resource in the database.

Type Parameters:

T - object type

Parameters:

entityClass - the entity class

requestScope - the request scope

uuid - the (optional) uuid

Returns:

persistent resource

createObject

public static <T> PersistentResource<T> createObject(PersistentResource<?> parent,
                                                     String parentRelationship,
                                                     Type<T> entityClass,
                                                     RequestScope requestScope,
                                                     Optional<String> uuid)

Create a resource in the database.

Type Parameters:

T - object type

Parameters:

parent - - The immediate ancestor in the lineage or null if this is a root.

parentRelationship - - The name of the parent relationship traversed to create this object.

entityClass - the entity class

requestScope - the request scope

uuid - the (optional) uuid

Returns:

persistent resource

matchesId

public boolean matchesId(String checkId)

Check whether an id matches for this persistent resource.

Specified by:

matchesId in interface PersistentResource<T>

Parameters:

checkId - the check id

Returns:

True if matches false otherwise

loadRecord

@NonNull
public static <T> @NonNull PersistentResource<T> loadRecord(EntityProjection projection,
                                                                     String id,
                                                                     RequestScope requestScope)
                                                              throws InvalidObjectIdentifierException

Load an single entity from the DB.

Type Parameters:

T - type of resource

Parameters:

projection - What to load from the DB.

id - the id

requestScope - the request scope

Returns:

resource persistent resource

Throws:

InvalidObjectIdentifierException - the invalid object identifier exception

loadRecords

public static io.reactivex.Observable<PersistentResource> loadRecords(EntityProjection projection,
                                                                      List<String> ids,
                                                                      RequestScope requestScope)

Load a collection from the datastore.

Parameters:

projection - the projection to load

requestScope - the request scope

ids - a list of object identifiers to optionally load. Can be empty.

Returns:

a filtered collection of resources loaded from the datastore.

updateAttribute

public boolean updateAttribute(String fieldName,
                               Object newVal)

Update attribute in existing resource.

Parameters:

fieldName - the field name

newVal - the new val

Returns:

true if object updated, false otherwise

updateRelation

public boolean updateRelation(String fieldName,
                              Set<PersistentResource> resourceIdentifiers)

Perform a full replacement on relationships. Here is an example: The following are ids for a hypothetical relationship. GIVEN: all (all the ids in the DB) = 1,2,3,4,5 mine (everything the current user has access to) = 1,2,3 requested (what the user wants to change to) = 3,6 THEN: deleted (what gets removed from the DB) = 1,2 final (what get stored in the relationship) = 3,4,5,6 BECAUSE: notMine = all - mine updated = (requested UNION mine) - (requested INTERSECT mine) deleted = (mine - requested) final = (notMine) UNION requested

Parameters:

fieldName - the field name

resourceIdentifiers - the resource identifiers

Returns:

True if object updated, false otherwise

updateToManyRelation

protected boolean updateToManyRelation(String fieldName,
                                       Set<PersistentResource> resourceIdentifiers,
                                       Set<PersistentResource> mine)

Updates a to-many relationship.

Parameters:

fieldName - the field name

resourceIdentifiers - the resource identifiers

mine - Existing, filtered relationships for field name

Returns:

true if updated. false otherwise

updateToOneRelation

protected boolean updateToOneRelation(String fieldName,
                                      Set<PersistentResource> resourceIdentifiers,
                                      Set<PersistentResource> mine)

Update a 2-one relationship.

Parameters:

fieldName - the field name

resourceIdentifiers - the resource identifiers

mine - Existing, filtered relationships for field name

Returns:

true if updated. false otherwise

clearRelation

public boolean clearRelation(String relationName)

Clear all elements from a relation.

Parameters:

relationName - Name of relation to clear

Returns:

True if object updated, false otherwise

removeRelation

public void removeRelation(String fieldName,
                           PersistentResource removeResource)

Remove a relationship.

Parameters:

fieldName - the field name

removeResource - the remove resource

relationshipAlreadyExists

public boolean relationshipAlreadyExists(String fieldName,
                                         PersistentResource toAdd)

Checks whether the new entity is already a part of the relationship.

Parameters:

fieldName - which relation link

toAdd - the new relation

Returns:

boolean representing the result of the check This method does not handle the case where the toAdd entity is newly created, since newly created entities have null id there is no easy way to check for identity

addRelation

public void addRelation(String fieldName,
                        PersistentResource newRelation)

Add relation link from a given parent resource to a child resource.

Parameters:

fieldName - which relation link

newRelation - the new relation

checkTransferablePermission

protected void checkTransferablePermission(Set<PersistentResource> resourceIdentifiers)

Check if adding or updating a relation is allowed.

Parameters:

resourceIdentifiers - The persistent resources that are being added

deleteResource

public void deleteResource()
                    throws ForbiddenAccessException

Delete an existing entity.

Throws:

ForbiddenAccessException - the forbidden access exception

getId

public String getId()

Get resource ID.

Specified by:

getId in interface PersistentResource<T>

Returns:

ID id

setId

public void setId(String id)

Set resource ID.

Parameters:

id - resource id

isIdGenerated

public boolean isIdGenerated()

Indicates if the ID is generated or not.

Returns:

Boolean

getUUID

public Optional<String> getUUID()

Gets UUID.

Specified by:

getUUID in interface PersistentResource<T>

Returns:

the UUID

getRelation

public PersistentResource getRelation(Relationship relationship,
                                      String id)

Get relation looking for a _single_ id. NOTE: Filter expressions for this type are _not_ applied at this level.

Parameters:

relationship - The relationship

id - single id to lookup

Returns:

The PersistentResource of the sought id or null if does not exist.

getRelation

public io.reactivex.Observable<PersistentResource> getRelation(List<String> ids,
                                                               Relationship relationship)

Load a relation from the PersistentResource.

Parameters:

relationship - the relation

ids - a list of object identifiers to optionally load. Can be empty.

Returns:

PersistentResource relation

getRelationCheckedFiltered

public io.reactivex.Observable<PersistentResource> getRelationCheckedFiltered(Relationship relationship)

Get observable of resources from relation field.

Parameters:

relationship - relationship

Returns:

collection relation

checkRelation

protected boolean checkRelation(Relationship relationship)

Check the permissions of the relationship, and return true or false.

Parameters:

relationship - The relationship to the entity

Returns:

True if the relationship to the entity has valid permissions for the user

getRelationChecked

public io.reactivex.Observable<PersistentResource> getRelationChecked(Relationship relationship)

Get collection of resources from relation field. Does not filter the relationship and does not invoke lifecycle hooks.

Parameters:

relationship - the relationship to fetch

Returns:

collection relation

getRelationshipType

public RelationshipType getRelationshipType(String relation)

Get a relationship type.

Parameters:

relation - Name of relationship

Returns:

Relationship type. RelationshipType.NONE if not found.

getAttribute

@Deprecated
public Object getAttribute(String attr)

Deprecated.

Get the value for a particular attribute (i.e. non-relational field)

Parameters:

attr - Attribute name

Returns:

Object value for attribute

getAttribute

public Object getAttribute(Attribute attr)

Get the value for a particular attribute (i.e. non-relational field)

Parameters:

attr - the Attribute

Returns:

Object value for attribute

getObject

public T getObject()

Wrapped Entity bean.

Specified by:

getObject in interface PersistentResource<T>

Returns:

bean object

setObject

public void setObject(T obj)

Sets object.

Parameters:

obj - the obj

getResourceType

public Type<T> getResourceType()

Entity type.

Specified by:

getResourceType in interface PersistentResource<T>

Returns:

type resource class

getTypeName

public String getTypeName()

Gets type.

Specified by:

getTypeName in interface PersistentResource<T>

Returns:

the type

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

isNewlyCreated

public boolean isNewlyCreated()

Returns whether or not this resource was created in this transaction.

Returns:

True if this resource is newly created.

getLineage

public ResourceLineage getLineage()

Gets lineage.

Returns:

the lineage

getDictionary

public EntityDictionary getDictionary()

Gets dictionary.

Returns:

the dictionary

getRequestScope

public RequestScope getRequestScope()

Gets request scope.

Specified by:

getRequestScope in interface PersistentResource<T>

Returns:

the request scope

toResource

public Resource toResource()

Convert a persistent resource to a resource.

Returns:

a resource

toResource

public Resource toResource(EntityProjection projection)

Fetch a resource with support for lambda function for getting relationships and attributes.

Returns:

The Resource

toResource

public Resource toResource(Map<String,Relationship> relationships,
                           Map<String,Object> attributes)

Convert a persistent resource to a resource.

Parameters:

relationships - The relationships

attributes - The attributes

Returns:

The Resource

getRelationships

protected Map<String,Relationship> getRelationships()

Get relationship mappings.

Returns:

Relationship mapping

getRelationshipsWithRelationshipFunction

protected Map<String,Relationship> getRelationshipsWithRelationshipFunction(Function<String,io.reactivex.Observable<PersistentResource>> relationshipFunction)

Get relationship mappings.

Parameters:

relationshipFunction - a function to load the value of a relationship. Takes a string of the relationship name and returns the relationship's value.

Returns:

Relationship mapping

getAttributes

protected Map<String,Object> getAttributes()

Get attributes mapping from entity.

Returns:

Mapping of attributes to objects

setValueChecked

protected void setValueChecked(String fieldName,
                               Object newValue)

Sets value.

Parameters:

fieldName - the field name

newValue - the new value

nullValue

protected void nullValue(String fieldName,
                         PersistentResource oldValue)

Nulls the relationship or attribute and checks update permissions. Invokes the set[fieldName] method on the target object OR set the field with the corresponding name.

Parameters:

fieldName - the field name to set or invoke equivalent set method

oldValue - the old value

getValueChecked

protected Object getValueChecked(Attribute attribute)

Gets a value from an entity and checks read permissions.

Parameters:

attribute - the attribute to fetch.

Returns:

value value

getValueUnchecked

protected Object getValueUnchecked(String fieldName)

Retrieve an object without checking read permissions (i.e. value is used internally and not sent to others)

Parameters:

fieldName - the field name

Returns:

Value

addToCollection

protected boolean addToCollection(Collection collection,
                                  String collectionName,
                                  PersistentResource toAdd)

Adds a new element to a collection and tests update permission.

Parameters:

collection - the collection

collectionName - the collection name

toAdd - the to add

Returns:

True if added to collection false otherwise (i.e. element already in collection)

delFromCollection

protected void delFromCollection(Collection collection,
                                 String collectionName,
                                 PersistentResource toDelete,
                                 boolean isInverseCheck)

Deletes an existing element in a collection and tests update and delete permissions.

Parameters:

collection - the collection

collectionName - the collection name

toDelete - the to delete

isInverseCheck - Whether or not the deletion is already coming from cleaning up an inverse. Without this parameter, we could find ourselves in a loop of checks. TODO: This is a band-aid for a quick fix. This should certainly be refactored.

setValue

protected void setValue(String fieldName,
                        Object value)

Invoke the set[fieldName] method on the target object OR set the field with the corresponding name.

Parameters:

fieldName - the field name to set or invoke equivalent set method

value - the value to set

getValue

public static Object getValue(Object target,
                              String fieldName,
                              RequestScope requestScope)

Invoke the get[fieldName] method on the target object OR get the field with the corresponding name.

Parameters:

target - the object to get

fieldName - the field name to get or invoke equivalent get method

requestScope - the request scope

Returns:

the value

deleteInverseRelation

protected void deleteInverseRelation(String relationName,
                                     Object inverseEntity)

If a bidirectional relationship exists, attempts to delete itself from the inverse relationship. Given A to B as the relationship, A corresponds to this and B is the inverse.

Parameters:

relationName - The name of the relationship on this (A) object.

inverseEntity - The value (B) which has been deleted from this object.

addInverseRelation

protected void addInverseRelation(String relationName,
                                  Object inverseObj)

If a bidirectional relationship exists, attempts to add itself to the inverse relationship. Given A to B as the relationship, A corresponds to this and B is the inverse.

Parameters:

relationName - The name of the relationship on this (A) object.

inverseObj - The value (B) which has been added to this object.

filter

protected static io.reactivex.Observable<PersistentResource> filter(Class<? extends Annotation> permission,
                                                                    Optional<FilterExpression> filter,
                                                                    Set<String> requestedFields,
                                                                    io.reactivex.Observable<PersistentResource> resources)

Filter a set of PersistentResources. Verify fields have ReadPermission on filter join.

Parameters:

permission - the permission

resources - the resources

Returns:

Filtered set of resources

filterFields

protected Set<String> filterFields(Collection<String> fields)

Filter a set of fields.

Parameters:

fields - the fields

Returns:

Filtered set of fields

checkIncludeSparseField

protected static boolean checkIncludeSparseField(Map<String,Set<String>> sparseFields,
                                                 String type,
                                                 String fieldName)

auditField

protected void auditField(ChangeSpec changeSpec)

Audit an action on field.

Parameters:

changeSpec - Change spec for audit

auditClass

protected void auditClass(Audit.Action action,
                          ChangeSpec changeSpec)

Audit an action on an entity.

Parameters:

action - the action

changeSpec - the change that occurred

firstOrNullIfEmpty

public static <T> T firstOrNullIfEmpty(io.reactivex.Observable<T> coll)