cdmlib-services/src/main/java/eu/etaxonomy/cdm/api/service/IService.java

   1 /**
   2 * Copyright (C) 2007 EDIT
   3 * European Distributed Institute of Taxonomy
   4 * http://www.e-taxonomy.eu
   5 *
   6 * The contents of this file are subject to the Mozilla Public License Version 1.1
   7 * See LICENSE.TXT at the top of this package for the full license terms.
   8 */
   9
  10 package eu.etaxonomy.cdm.api.service;
  11
  12
  13 import java.util.Collection;
  14 import java.util.List;
  15 import java.util.Map;
  16 import java.util.Set;
  17 import java.util.UUID;
  18
  19 import org.hibernate.LockOptions;
  20 import org.hibernate.Session;
  21 import org.hibernate.event.spi.MergeEvent;
  22
  23 import eu.etaxonomy.cdm.api.service.pager.Pager;
  24 import eu.etaxonomy.cdm.model.common.ICdmBase;
  25 import eu.etaxonomy.cdm.persistence.dao.initializer.IBeanInitializer;
  26 import eu.etaxonomy.cdm.persistence.dto.MergeResult;
  27 import eu.etaxonomy.cdm.persistence.hibernate.PostMergeEntityListener;
  28 import eu.etaxonomy.cdm.persistence.query.Grouping;
  29 import eu.etaxonomy.cdm.persistence.query.OrderHint;
  30
  31
  32 /**
  33  * @author a.mueller
  34  *
  35  */
  36 /**
  37  * @author a.kohlbecker
  38  * @date 23.03.2009
  39  *
  40  * @param <T>
  41  */
  42 public interface IService<T extends ICdmBase>{
  43
  44     // FIXME what does this method do?
  45     public void clear();
  46
  47     /**
  48      * Obtain the specified lock mode on the given object t
  49      * <BR>
  50      * NOTE: with hibernate 4 we changed parameter lockMode to lockOptions. LockOptions can be created from LockMode.
  51      */
  52     public void lock(T t, LockOptions lockOptions);
  53
  54     /**
  55      * Refreshes a given object t using the specified lockmode
  56      *
  57      * All bean properties given in the <code>propertyPaths</code> parameter are recursively initialized.
  58      * <p>
  59      * For detailed description and examples <b>please refer to:</b>
  60      * {@link IBeanInitializer#initialize(Object, List)}
  61      *
  62      * NOTE: in the case of lockmodes that hit the database (e.g. LockMode.READ), you will need to re-initialize
  63      * child propertiesto avoid a HibernateLazyInitializationException (even if the properties of the child
  64      * were initialized prior to the refresh).
  65      *
  66      * NOTE: with hibernate 4 we changed parameter lockMode to lockOptions. LockOptions can be created from LockMode.
  67      *
  68      * @param t
  69      * @param lockOptions
  70      */
  71     public void refresh(T t, LockOptions lockOptions, List<String> propertyPaths);
  72
  73     /**
  74      * Returns a count of all entities of type <T>  optionally restricted
  75      * to objects belonging to a class that that extends <T>
  76      *
  77      * @param clazz the class of entities to be counted (can be null to count all entities of type <T>)
  78      * @return a count of entities
  79      */
  80     public int count(Class<? extends T> clazz);
  81
  82     /**
  83      * Delete an existing persistent object
  84      *
  85      * @param persistentObject the object to be deleted
  86      * @return the unique identifier of the deleted entity
  87      * @return deleteResult
  88      */
  89     public DeleteResult delete(UUID persistentObjectUUID) ;
  90
  91
  92
  93     /**
  94      * Returns true if an entity of type <T> with a unique identifier matching the
  95      * identifier supplied exists in the database, or false if no such entity can be
  96      * found.
  97      * @param uuid the unique identifier of the entity required
  98      * @return an entity of type <T> matching the uuid, or null if that entity does not exist
  99      */
 100     public boolean exists(UUID uuid);
 101
 102     /**
 103      * Return a list of persisted entities that match the unique identifier
 104      * set supplied as an argument
 105      *
 106      * @param uuidSet the set of unique identifiers of the entities required
 107      * @return a list of entities of type <T>
 108      */
 109     public List<T> find(Set<UUID> uuidSet);
 110
 111     /**
 112      * Return a persisted entity that matches the unique identifier
 113      * supplied as an argument, or null if the entity does not exist
 114      *
 115      * @param uuid the unique identifier of the entity required
 116      * @return an entity of type <T>, or null if the entity does not exist or uuid is <code>null</code>
 117      */
 118     public T find(UUID uuid);
 119
 120
 121
 122         /**
 123          * Return a persisted entity that matches the unique identifier
 124      * supplied as an argument, or null if the entity does not exist.
 125      * <p>
 126      * The difference between this method and {@link #find(UUID) find} is
 127      * that this method makes the hibernate read query with the
 128      * {@link org.hibernate.FlushMode FlushMode} for the session set to 'MANUAL'
 129      * <p>
 130      * <b>WARNING:</b>This method should <em>ONLY</em> be used when it is absolutely
 131      * necessary and safe to ensure that the hibernate session is not flushed before a read
 132      * query. A use case for this is the {@link eu.etaxonomy.cdm.api.cache.CdmCacher CdmCacher},
 133      * (ticket #4276) where a call to {@link eu.etaxonomy.cdm.api.cache.CdmCacher#load(UUID) load}
 134      * the CDM Entity using the standard {@link #find(UUID) find} method results in recursion
 135      * due to the fact that the {@link #find(UUID) find} method triggers a hibernate session
 136      * flush which eventually could call {@link eu.etaxonomy.cdm.model.name.NonViralName#getNameCache getNameCache},
 137          * which in turn (in the event that name cache is null) eventually calls the
 138          * {@link eu.etaxonomy.cdm.api.cache.CdmCacher#load(UUID uuid) load} again.
 139          * Apart from these kind of exceptional circumstances, the standard {@link #find(UUID) find}
 140          * method should always be used to ensure that the persistence layer is always in sync with the
 141          * underlying database.
 142          *
 143          * @param uuid
 144          * @return an entity of type <T>, or null if the entity does not exist or uuid is <code>null</code>
 145          */
 146         public T findWithoutFlush(UUID uuid);
 147
 148     /**
 149      * Return a persisted entity that matches the database identifier
 150      * supplied as an argument, or null if the entity does not exist
 151      *
 152      * @param id the database identifier of the entity required
 153      * @return an entity of type <T>, or null if the entity does not exist
 154      */
 155     public T find(int id);
 156
 157     /**
 158      * Returns a <code>List</code> of persisted entities that match the database identifiers.
 159      * Returns an empty list if no identifier matches.
 160      *
 161      * @param idSet
 162      * @return
 163      * @deprecated use {@link #loadByIds(Set, List)} instead
 164      */
 165     @Deprecated
 166     public List<T> findById(Set<Integer> idSet);  //can't be called find(Set<Integer>) as this conflicts with find(Set<UUID)
 167
 168
 169     // FIXME should we expose this method?
 170     public Session getSession();
 171
 172     /**
 173      * Returns a sublist of objects matching the grouping projections supplied using the groups parameter
 174      *
 175      * It would be nice to be able to return a pager, but for the moment hibernate doesn't
 176      * seem to support this (HHH-3238 - impossible to get the rowcount for a criteria that has projections)
 177      *
 178      * @param clazz Restrict the query to objects of a certain class, or null for all objects of type T or subclasses
 179      * @param limit the maximum number of entities returned (can be null to return
 180      *            all entities)
 181      * @param start The (0-based) offset from the start of the recordset (can be null, equivalent of starting at the beginning of the recordset)
 182      * @param groups The grouping objects representing a projection, plus an optional ordering on that projected property
 183      * @param propertyPaths paths initialized on the returned objects - only applied to the objects returned from the first grouping
 184      * @return a list of arrays of objects, each matching the grouping objects supplied in the parameters.
 185      */
 186     public List<Object[]> group(Class<? extends T> clazz,Integer limit, Integer start, List<Grouping> groups, List<String> propertyPaths);
 187
 188     /**
 189      * Returns a list of entities of type <T> optionally restricted
 190      * to objects belonging to a class that that extends <T>
 191      *
 192      * @param type  The type of entities to return (can be null to count all entities of type <T>)
 193      * @param limit The maximum number of objects returned (can be null for all matching objects)
 194      * @param start The offset from the start of the result set (0 - based, can be null - equivalent of starting at the beginning of the recordset)
 195      * @param orderHints
 196      *            Supports path like <code>orderHints.propertyNames</code> which
 197      *            include *-to-one properties like createdBy.username or
 198      *            authorTeam.persistentTitleCache
 199      * @param propertyPaths properties to be initialized
 200      * @return
 201      */
 202     //TODO refactor to public <S extends T> List<T> list(Class<S> type, Integer limit, Integer start, List<OrderHint> orderHints, List<String> propertyPaths);
 203     public <S extends T>  List<S> list(Class<S> type, Integer limit, Integer start, List<OrderHint> orderHints, List<String> propertyPaths);
 204
 205     /**
 206      * Finds the cdm entity specified by the <code>uuid</code> parameter and
 207      * initializes all its *ToOne relations.
 208      *
 209      * @param uuid
 210      * @return the cdm entity or <code>null</code> if not object with given uuid exists or uuid is <code>null</code>
 211      */
 212     public T load(UUID uuid);
 213
 214     /**
 215      * Return a persisted entity that matches the database identifier
 216      * supplied as an argument, or null if the entity does not exist
 217      *
 218      * @param id the database identifier of the entity required
 219      * @param propertyPaths
 220      * @return
 221      */
 222     public T load(int id, List<String> propertyPaths);
 223
 224     /**
 225      * Finds the cdm entity specified by the <code>uuid</code> parameter and
 226      * recursively initializes all bean properties given in the
 227      * <code>propertyPaths</code> parameter.
 228      * <p>
 229      * For detailed description and examples <b>please refer to:</b>
 230      * {@link IBeanInitializer#initialize(Object, List)}
 231      *
 232      * @param uuid
 233      * @return the cdm entity or <code>null</code> if not object with given uuid exists or uuid is <code>null</code>
 234      */
 235     public T load(UUID uuid, List<String> propertyPaths);
 236
 237
 238     /**
 239      * Finds the cdm entities specified by the <code>uuids</code>,
 240      * recursively initializes all bean properties given in the
 241      * <code>propertyPaths</code> parameter and returns the initialised
 242      * entity list;
 243      * <p>
 244      * For detailed description and examples <b>please refer to:</b>
 245      * {@link IBeanInitializer#initialize(Object, List)}
 246      * @param uuids
 247      * @param propertyPaths
 248      * @return
 249      */
 250     public List<T> load(List<UUID> uuids, List<String> propertyPaths);
 251
 252     /**
 253      * Copy the state of the given object onto the persistent object with the same identifier.
 254      *
 255      * @param transientObject the entity to be merged
 256      * @return The unique identifier of the persisted entity
 257      */
 258     public T merge(T transientObject);
 259
 260     /**
 261      * Returns a paged list of entities of type <T> optionally restricted
 262      * to objects belonging to a class that that extends <T>
 263      *
 264      * @param type  The type of entities to return (can be null to count all entities of type <T>)
 265      * @param pageSize The maximum number of objects returned (can be null for all matching objects)
 266      * @param pageNumber The offset (in pageSize chunks) from the start of the result set (0 - based,
 267      *                   can be null, equivalent of starting at the beginning of the recordset)
 268      * @param orderHints
 269      *            Supports path like <code>orderHints.propertyNames</code> which
 270      *            include *-to-one properties like createdBy.username or
 271      *            authorTeam.persistentTitleCache
 272      * @param propertyPaths properties to be initialized
 273      * @return a pager of objects of type <T>
 274      */
 275     public <S extends T> Pager<S> page(Class<S> type, Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, List<String> propertyPaths);
 276
 277     /**
 278      * Re-read the state of the given instance from the underlying database.
 279      *
 280      * Hibernate claims that it is inadvisable to use refresh in long-running-sessions.
 281      * I don't really see where we would get into a situation where problems as discussed
 282      * this forum thread would apply for our scenario
 283      *
 284      * http://forum.hibernate.org/viewtopic.php?t=974544
 285      *
 286      * @param persistentObject the object to be refreshed
 287      * @return the unique identifier
 288      */
 289     public UUID refresh(T persistentObject);
 290
 291     public List<T> rows(String tableName, int limit, int start);
 292
 293     /**
 294      * Save a collection containing new entities (persists the entities)
 295      * @param newInstances the new entities to be persisted
 296      * @return A Map containing the new entities, keyed using the generated UUID's
 297      *         of those entities
 298      */
 299     public Map<UUID,T> save(Collection<T> newInstances);
 300
 301     /**
 302      * Save a new entity (persists the entity)
 303      * @param newInstance the new entity to be persisted
 304      * @return A generated UUID for the new persistent entity
 305      */
 306     public T save(T newInstance);
 307
 308     /**
 309      * Save a new entity or update the persistent state of an existing
 310      * transient entity that has been persisted previously
 311      *
 312      * @param transientObject the entity to be persisted
 313      * @return The unique identifier of the persisted entity
 314      */
 315     public UUID saveOrUpdate(T transientObject);
 316
 317     /**
 318      * Save new entities or update the persistent state of existing
 319      * transient entities that have been persisted previously
 320      *
 321      * @param transientObjects the entities to be persisted
 322      * @return The unique identifier of the persisted entity
 323      */
 324     public Map<UUID,T> saveOrUpdate(Collection<T> transientObjects);
 325
 326     /**
 327      * Update the persistent state of an existing transient entity
 328      * that has been persisted previously
 329      *
 330      * @param transientObject the entity to be persisted
 331      * @return The unique identifier of the persisted entity
 332      */
 333     public UUID update(T transientObject);
 334
 335     /**
 336      * Simply calls the load method.
 337      * Required specifically for the editor to allow load calls which
 338      * can also update the session cache.
 339      *
 340      * @param uuid
 341      * @return
 342      */
 343     public T loadWithUpdate(UUID uuid);
 344
 345     /**
 346      * Method that lists the objects matching the example provided.
 347      * The includeProperties property is used to specify which properties of the example are used.
 348      *
 349      * If includeProperties is null or empty, then all literal properties are used (restrictions are
 350      * applied as in the Hibernate Query-By-Example API call Example.create(object)).
 351      *
 352      * If includeProperties is not empty then only literal properties that are named in the set are used to
 353      * create restrictions, *PLUS* any *ToOne related entities. Related entities are matched on ID, not by
 354      * their internal literal values (e.g. the call is criteria.add(Restrictions.eq(property,relatedObject)), not
 355      * criteria.createCriteria(property).add(Example.create(relatedObject)))
 356      *
 357      * @param example
 358      * @param includeProperties
 359      * @param limit the maximum number of entities returned (can be null to return
 360      *            all entities)
 361      * @param start The (0-based) offset from the start of the recordset
 362      * @param orderHints
 363      *            Supports path like <code>orderHints.propertyNames</code> which
 364      *            include *-to-one properties like createdBy.username or
 365      * @param propertyPaths paths initialized on the returned objects - only applied to the objects returned from the first grouping
 366      * @return a list of matching objects
 367      */
 368     public List<T> list(T example, Set<String> includeProperties, Integer limit, Integer start, List<OrderHint> orderHints, List<String> propertyPaths);
 369
 370         public DeleteResult delete(T persistentObject);
 371
 372     /**
 373      * Deletes a collection of persistent objects correponding to the
 374      * given list of uuids. The result will have status as ok if even one
 375      * of the deletes is successful, else error.
 376      *
 377      * @param persistentObjectUUIDs uuids of persistent objects to delete
 378      * @return DeleteResult object
 379      */
 380     public DeleteResult delete(Collection<UUID> persistentObjectUUIDs);
 381
 382     /**
 383      * Merges a list of detached objects and returns the new
 384      * list of merged objects
 385      *
 386      * @param detachedObjects
 387      * @return a list of merged objects
 388      */
 389     public List<T> merge(List<T> detachedObjects);
 390
 391     /**
 392      * Loads a batch of entities referenced by their ids.
 393      *
 394      * @param idSet
 395      * @param propertyPaths
 396      * @return
 397      */
 398     List<T> loadByIds(List<Integer> idSet, List<String> propertyPaths);
 399
 400     /**
 401      * This method allows for the possibility of returning the input transient
 402      * entities instead of the merged persistent entity
 403      *
 404      * WARNING : This method should never be used when the objective of the merge
 405      * is to attach to an existing session which is the standard use case.
 406      * This method should only be used in the
 407      * case of an external call which does not use hibernate sessions and is
 408      * only interested in the entity as a POJO. Apart from the session information
 409      * the only other difference between the transient and persisted object is in the case
 410      * of new objects (id=0) where hibernate sets the id after commit. This id is copied
 411      * over to the transient entity in {@link PostMergeEntityListener#onMerge(MergeEvent,Map)}
 412      * making the two objects identical and allowing the transient object to be used further
 413      * as a POJO
 414      *
 415      * @param detachedObjects
 416      * @param returnTransientEntity
 417      * @return
 418      */
 419     public List<MergeResult<T>> merge(List<T> detachedObjects, boolean returnTransientEntity);
 420
 421     /**
 422      * This method allows for the possibility of returning the input transient
 423      * entity instead of the merged persistent entity
 424      *
 425      * WARNING : This method should never be used when the objective of the merge
 426      * is to attach to an existing session which is the standard use case.
 427      * This method should only be used in the case of an external call which does
 428      * not use hibernate sessions and is only interested in the entity as a POJO.
 429      * This method returns the root merged transient entity as well as all newly merged
 430      * persistent entities within the return object.
 431      *
 432      * @param newInstance
 433      * @param returnTransientEntity
 434      * @return
 435      */
 436     public MergeResult<T> merge(T newInstance, boolean returnTransientEntity);
 437
 438 }