Package org.nuxeo.ecm.core.storage.sql

Class Fragment

java.lang.Object

org.nuxeo.ecm.core.storage.sql.Fragment

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

CollectionFragment, SimpleFragment

public abstract class Fragment
extends Object
implements Serializable

A rich value corresponding to one row or a collection of rows in a table.

In addition to the basic Row, this holds the old values (to check dirty state), the state and a reference to the session.

This class has two kinds of state-changing methods:

• the "set" ones, which only change the state,
• the "mark" ones, which change the state and do the corresponding changes in the pristine/modified maps of the context.

Author:

Florent Guillaume

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Fragment.State	The possible states of a fragment.

Field Summary

Fields

Modifier and Type	Field	Description
protected PersistenceContext	context
protected Serializable[]	oldvalues	The row old values, from the time of construction / refetch.
protected Row	row	The row holding the data.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Fragment(Row row, Fragment.State state, PersistenceContext context)	Constructs a Fragment from a Row.

Method Summary

Modifier and Type	Method	Description
protected void	accessed()	Checks that access to the fragment is possible.
void	clearDirty()	Clears the dirty state.
Serializable	getId()	Gets the id.
abstract RowMapper.RowUpdate	getRowUpdate()	Returns the row update to do in the database to write this value.
Fragment.State	getState()	Gets the state.
protected void	markModified()	Marks the fragment modified.
protected abstract Fragment.State	refetch()	Refetches this fragment from the database.
protected abstract Fragment.State	refetchDeleted()	Resets the data for a fragment that was invalidated by deletion.
protected void	setDeleted(boolean primary)	Marks the fragment deleted.
protected void	setDetached()	Detaches the fragment from its persistence context.
void	setId(Serializable id)	Sets the id.
protected void	setInvalidatedDeleted()	Sets the fragment in the "invalidated from a deletion" state.
protected void	setInvalidatedModified()	Sets the fragment in the "invalidated from a modification" state.
protected void	setPristine()	Sets the (created/modified) fragment in the pristine state.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

row

protected Row row

The row holding the data.

oldvalues

protected Serializable[] oldvalues

The row old values, from the time of construction / refetch. The size of the the array is following #row.values.length.

context

protected PersistenceContext context

Constructor Detail

Fragment

protected Fragment(Row row,
                   Fragment.State state,
                   PersistenceContext context)

Constructs a Fragment from a Row.

Parameters:

row - the row

state - the initial state for the fragment

context - the persistence context to which the fragment is tied, or null

Method Detail

getState

public Fragment.State getState()

Gets the state.

Returns:

the state

setId

public void setId(Serializable id)

Sets the id. This only used at most once to change a temporary id to the persistent one.

Parameters:

id - the new persistent id

getId

public Serializable getId()

Gets the id.

Returns:

the id

clearDirty

public void clearDirty()

Clears the dirty state.

getRowUpdate

public abstract RowMapper.RowUpdate getRowUpdate()

Returns the row update to do in the database to write this value.

Returns:

a row update, or null if the value is unchanged since last clear

Since:

8.3

refetch

protected abstract Fragment.State refetch()

Refetches this fragment from the database. Needed when an invalidation has been received and the fragment is accessed again.

Returns:

the new state, Fragment.State.PRISTINE or Fragment.State.ABSENT

refetchDeleted

protected abstract Fragment.State refetchDeleted()

Resets the data for a fragment that was invalidated by deletion.

Returns:

the new state, Fragment.State.PRISTINE or Fragment.State.ABSENT

accessed

protected void accessed()

Checks that access to the fragment is possible. Called internally before a get, so that invalidated fragments can be refetched.

markModified

protected void markModified()

Marks the fragment modified. Called internally after a put/set.

setDeleted

protected void setDeleted(boolean primary)

Marks the fragment deleted. Called after a remove.

setDetached

protected void setDetached()

Detaches the fragment from its persistence context. The caller makes sure that the fragment is removed from the context map.

setPristine

protected void setPristine()

Sets the (created/modified) fragment in the pristine state. Called after a save.

setInvalidatedModified

protected void setInvalidatedModified()

Sets the fragment in the "invalidated from a modification" state. This is called:

• when a database operation does non-tracked changes, which means that on access a refetch will be needed,
• during post-commit invalidation.

setInvalidatedDeleted

protected void setInvalidatedDeleted()

Sets the fragment in the "invalidated from a deletion" state. This is called:

• when a database operation does a delete,
• during post-commit invalidation.

toString

public String toString()

Overrides:

toString in class Object