org.yawlfoundation.yawl.util

Class HibernateEngine

java.lang.Object

org.yawlfoundation.yawl.util.HibernateEngine

Direct Known Subclasses:

HibernateEngine, Persister

public class HibernateEngine
extends java.lang.Object

This singleton class provides db & persistence support via Hibernate.

Author:

Michael Adams

Created/Last Date:

03/08/2007 last update: 18/09/2014 (for v3.0+)

Field Summary

Fields

Modifier and Type	Field and Description
static int	DB_DELETE
static int	DB_INSERT
static int	DB_UPDATE

Constructor Summary

Constructors

Constructor and Description
HibernateEngine(boolean persistenceOn, java.util.Set<java.lang.Class> classes)
HibernateEngine(boolean persistenceOn, java.util.Set<java.lang.Class> classes, java.util.Properties props) The constuctor - called from getInstance()

Method Summary

Modifier and Type	Method and Description
org.hibernate.Transaction	beginTransaction()
void	closeFactory()
void	commit()
org.hibernate.Query	createQuery(java.lang.String queryString)
boolean	exec(java.lang.Object obj, int action)
boolean	exec(java.lang.Object obj, int action, boolean commit) persists the object instance passed
boolean	exec(java.lang.Object obj, int action, org.hibernate.Transaction tx) persists the object instance passed
java.util.List	execJoinQuery(java.lang.String table, java.lang.String field, java.lang.String value) executes a join query.
java.util.List	execQuery(java.lang.String queryString) executes a Query object based on the hql string passed
java.util.List	execSQLQuery(java.lang.String queryString) executes a plain SQL Query
int	execUpdate(java.lang.String queryString)
int	execUpdate(java.lang.String queryString, boolean commit)
java.lang.Object	get(java.lang.Class claz, java.io.Serializable key)
java.lang.Object	get(java.lang.Class claz, java.io.Serializable key, boolean doCommit)
java.util.List	getByCriteria(java.lang.Class claz, boolean commit, org.hibernate.criterion.Criterion... criteria)
java.util.List	getByCriteria(java.lang.Class claz, org.hibernate.criterion.Criterion... criteria)
java.util.List	getObjectsForClass(java.lang.String className) returns all the instances currently persisted for the class passed
java.util.List	getObjectsForClassWhere(java.lang.String className, java.lang.String whereClause) returns all the instances currently persisted for the class passed that match the condition specified in the where clause
org.hibernate.Transaction	getOrBeginTransaction()
boolean	isAvailable(java.lang.String tableName)
boolean	isPersisting()
java.lang.Object	load(java.lang.Class claz, java.io.Serializable key)
java.lang.Object	load(java.lang.Class claz, java.io.Serializable key, boolean doCommit)
void	rollback()
java.lang.Object	selectScalar(java.lang.String className, java.lang.String field, java.lang.String value) gets a scalar value (as an object) based on the sql string passed
void	setPersisting(boolean persist)

Methods inherited from class java.lang.Object

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

Field Detail

DB_UPDATE

public static final int DB_UPDATE

See Also:

Constant Field Values

DB_DELETE

public static final int DB_DELETE

See Also:

Constant Field Values

DB_INSERT

public static final int DB_INSERT

See Also:

Constant Field Values

Constructor Detail

HibernateEngine

public HibernateEngine(boolean persistenceOn,
                       java.util.Set<java.lang.Class> classes,
                       java.util.Properties props)
                throws org.hibernate.HibernateException

The constuctor - called from getInstance()

Throws:

org.hibernate.HibernateException

HibernateEngine

public HibernateEngine(boolean persistenceOn,
                       java.util.Set<java.lang.Class> classes)

Method Detail

isAvailable

public boolean isAvailable(java.lang.String tableName)

Returns:

true if a table of 'tableName' currently exists and has at least one row

setPersisting

public void setPersisting(boolean persist)

isPersisting

public boolean isPersisting()

Returns:

true if this instance is persisting

exec

public boolean exec(java.lang.Object obj,
                    int action)

exec

public boolean exec(java.lang.Object obj,
                    int action,
                    boolean commit)

persists the object instance passed

Parameters:

obj - - an instance of the object to persist

action - - type type of action performed

Returns:

true if persist was successful, false if otherwise

exec

public boolean exec(java.lang.Object obj,
                    int action,
                    org.hibernate.Transaction tx)

persists the object instance passed

Parameters:

obj - - an instance of the object to persist

action - - type type of action performed

tx - - an active Transaction object. NOTE: Any objects persisted via this method will not be permanently actioned until the transaction is committed via a call to 'commit()'.

Returns:

true if persist was successful, false if otherwise

getOrBeginTransaction

public org.hibernate.Transaction getOrBeginTransaction()

execQuery

public java.util.List execQuery(java.lang.String queryString)

executes a Query object based on the hql string passed

Parameters:

queryString - - the hibernate query to execute

Returns:

the List of objects returned, or null if the query has some problem

execSQLQuery

public java.util.List execSQLQuery(java.lang.String queryString)

executes a plain SQL Query

Parameters:

queryString - - the SQL query to execute

Returns:

the List of objects returned, or null if the query has some problem

execUpdate

public int execUpdate(java.lang.String queryString)

execUpdate

public int execUpdate(java.lang.String queryString,
                      boolean commit)

createQuery

public org.hibernate.Query createQuery(java.lang.String queryString)

beginTransaction

public org.hibernate.Transaction beginTransaction()

load

public java.lang.Object load(java.lang.Class claz,
                             java.io.Serializable key)

load

public java.lang.Object load(java.lang.Class claz,
                             java.io.Serializable key,
                             boolean doCommit)

get

public java.lang.Object get(java.lang.Class claz,
                            java.io.Serializable key)

get

public java.lang.Object get(java.lang.Class claz,
                            java.io.Serializable key,
                            boolean doCommit)

getByCriteria

public java.util.List getByCriteria(java.lang.Class claz,
                                    org.hibernate.criterion.Criterion... criteria)

getByCriteria

public java.util.List getByCriteria(java.lang.Class claz,
                                    boolean commit,
                                    org.hibernate.criterion.Criterion... criteria)

commit

public void commit()

rollback

public void rollback()

closeFactory

public void closeFactory()

execJoinQuery

public java.util.List execJoinQuery(java.lang.String table,
                                    java.lang.String field,
                                    java.lang.String value)

executes a join query. For example, passing ("car", "part", "pid") will return a list of 'car' objects that have in their 'part' property (a Set) a part with a key id="pid"

Parameters:

table - the parent table - returned objects are of this class

field - the property name of the [Set] column in the parent table

value - the id of the child object in the set to match

Returns:

a List of objects of class 'table' that have, in their [Set] property called 'field', an object with an key field value of 'value'

selectScalar

public java.lang.Object selectScalar(java.lang.String className,
                                     java.lang.String field,
                                     java.lang.String value)

gets a scalar value (as an object) based on the sql string passed

Parameters:

className - - the type of object to select

field - - the column name which contains the queried value

value - - the value to find in the 'field' column

Returns:

the first (or only) object matching 'where [field] = [value]'

getObjectsForClass

public java.util.List getObjectsForClass(java.lang.String className)

returns all the instances currently persisted for the class passed

Parameters:

className - - the name of the class to retrieve instances of

Returns:

a List of the instances retrieved

getObjectsForClassWhere

public java.util.List getObjectsForClassWhere(java.lang.String className,
                                              java.lang.String whereClause)

returns all the instances currently persisted for the class passed that match the condition specified in the where clause

Parameters:

className - the name of the class to retrieve instances of

whereClause - the condition (without the 'where' part) e.g. "age=21"

Returns:

a List of the instances retrieved