Memento (Nuxeo ECM Projects 5.5-SNAPSHOT API Documentation)

All Known Implementing Classes:

XMLMemento
```
public interface Memento
```
Interface to a memento used for saving the important state of an object in a form that can be persisted in the file system.
Mementos were designed with the following requirements in mind:
1. Certain objects need to be saved and restored across platform sessions.
2. When an object is restored, an appropriate class for an object might not be available. It must be possible to skip an object in this case.
3. When an object is restored, the appropriate class for the object may be different from the one when the object was originally saved. If so, the new class should still be able to read the old form of the data.
Mementos meet these requirements by providing support for storing a mapping of arbitrary string keys to primitive values, and by allowing mementos to have other mementos as children (arranged into a tree). A robust external storage format based on XML is used.
The key for an attribute may be any alpha numeric value. However, the value of TAG_ID is reserved for internal use.
This interface is not intended to be implemented or extended by clients.

Field Summary

Fields
Modifier and Type Field and Description

static String TAG_ID
Special reserved key used to store the memento id (value "org.eclipse.ui.id").

Fields
Modifier and Type	Field and Description
`static String`	`TAG_ID` Special reserved key used to store the memento id (value `"org.eclipse.ui.id"`).

Method Summary

Methods
Modifier and Type	Method and Description
`Memento`	`createChild(String type)` Creates a new child of this memento with the given type.
`Memento`	`createChild(String type, String id)` Creates a new child of this memento with the given type and id.
`Boolean`	`getBoolean(String key)` Returns the boolean value of the given key.
`Memento`	`getChild(String type)` Returns the first child with the given type id.
`Memento[]`	`getChildren(String type)` Returns all children with the given type id.
`Float`	`getFloat(String key)` Returns the floating point value of the given key.
`String`	`getID()` Returns the id for this memento.
`Integer`	`getInteger(String key)` Returns the integer value of the given key.
`String`	`getString(String key)` Returns the string value of the given key.
`String`	`getTextData()` Returns the data of the Text node of the memento.
`void`	`putBoolean(String key, boolean value)` Sets the value of the given key to the given boolean.
`void`	`putFloat(String key, float value)` Sets the value of the given key to the given floating point number.
`void`	`putInteger(String key, int value)` Sets the value of the given key to the given integer.
`void`	`putMemento(Memento memento)` Copy the attributes and children from `memento` to the receiver.
`void`	`putString(String key, String value)` Sets the value of the given key to the given string.
`void`	`putTextData(String data)` Sets the memento's Text node to contain the given data.

- Field Detail
  - TAG_ID
```
static final String TAG_ID
```
    Special reserved key used to store the memento id (value "org.eclipse.ui.id").
    
    See Also:
    getID(), Constant Field Values
- Method Detail
  - createChild
```
Memento createChild(String type)
```
    Creates a new child of this memento with the given type.
    The getChild and getChildren methods are used to retrieve children of a given type.
    
    Parameters:
    type - the type
    
    Returns:
    a new child memento
    See Also:
    getChild(java.lang.String), getChildren(java.lang.String)
  - createChild
```
Memento createChild(String type,
                  String id)
```
    Creates a new child of this memento with the given type and id. The id is stored in the child memento (using a special reserved key, TAG_ID) and can be retrieved using getId.
    The getChild and getChildren methods are used to retrieve children of a given type.
    
    Parameters:
    type - the type
    id - the child id
    
    Returns:
    a new child memento with the given type and id
    See Also:
    getID()
  - getChild
```
Memento getChild(String type)
```
    Returns the first child with the given type id.
    
    Parameters:
    type - the type id
    
    Returns:
    the first child with the given type
  - getChildren
```
Memento[] getChildren(String type)
```
    Returns all children with the given type id.
    
    Parameters:
    type - the type id
    
    Returns:
    an array of children with the given type
  - getFloat
```
Float getFloat(String key)
```
    Returns the floating point value of the given key.
    
    Parameters:
    key - the key
    
    Returns:
    the value, or null if the key was not found or was found but was not a floating point number
  - getID
```
String getID()
```
    Returns the id for this memento.
    
    Returns:
    the memento id, or null if none
    See Also:
    createChild(String, String)
  - getInteger
```
Integer getInteger(String key)
```
    Returns the integer value of the given key.
    
    Parameters:
    key - the key
    
    Returns:
    the value, or null if the key was not found or was found but was not an integer
  - getBoolean
```
Boolean getBoolean(String key)
```
    Returns the boolean value of the given key.
    
    Parameters:
    key - the key
    
    Returns:
    the value, or null if the key was not found or was found but was not an integer
  - getString
```
String getString(String key)
```
    Returns the string value of the given key.
    
    Parameters:
    key - the key
    
    Returns:
    the value, or null if the key was not found
  - getTextData
```
String getTextData()
```
    Returns the data of the Text node of the memento. Each memento is allowed only one Text node.
    
    Returns:
    the data of the Text node of the memento, or null if the memento has no Text node.
    Since:
    
    2.0
  - putFloat
```
void putFloat(String key,
            float value)
```
    Sets the value of the given key to the given floating point number.
    
    Parameters:
    key - the key
    value - the value
  - putInteger
```
void putInteger(String key,
              int value)
```
    Sets the value of the given key to the given integer.
    
    Parameters:
    key - the key
    value - the value
  - putMemento
```
void putMemento(Memento memento)
```
    Copy the attributes and children from memento to the receiver.
    
    Parameters:
    memento - the Memento to be copied.
  - putString
```
void putString(String key,
             String value)
```
    Sets the value of the given key to the given string.
    
    Parameters:
    key - the key
    value - the value
  - putBoolean
```
void putBoolean(String key,
              boolean value)
```
    Sets the value of the given key to the given boolean.
    
    Parameters:
    key - the key
    value - the value
  - putTextData
```
void putTextData(String data)
```
    Sets the memento's Text node to contain the given data. Creates the Text node if none exists. If a Text node does exist, it's current contents are replaced. Each memento is allowed only one text node.
    
    Parameters:
    data - the data to be placed on the Text node
    Since:
    
    2.0

Interface Memento

Field Summary

Method Summary

Field Detail

TAG_ID

Method Detail

createChild

createChild

getChild

getChildren

getFloat

getID

getInteger

getBoolean

getString

getTextData

putFloat

putInteger

putMemento

putString

putBoolean

putTextData