ChangeTrackingMap

java.lang.Object
- org.fuin.utils4j.ChangeTrackingMap

All Implemented Interfaces:

java.util.Map, Taggable
```
public class ChangeTrackingMap
extends java.lang.Object
implements java.util.Map, Taggable
```
A wrapper for maps that keeps track of all changes made to the map since construction. Only adding, replacing or deleting elements is tracked (not changes inside the objects). It's also possible to revert all changes.

Nested Class Summary
- Nested classes/interfaces inherited from interface java.util.Map
  java.util.Map.Entry<K,V>

Constructor Summary

Constructors
Constructor and Description

ChangeTrackingMap(java.util.Map map)
Constructor with covered map.

Constructors
Constructor and Description
`ChangeTrackingMap(java.util.Map map)` Constructor with covered map.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clear()`
`boolean`	`containsKey(java.lang.Object key)`
`boolean`	`containsValue(java.lang.Object value)`
`java.util.Set`	`entrySet()`
`java.lang.Object`	`get(java.lang.Object key)`
`java.util.Map`	`getAdded()` Returns added elements.
`java.util.Map`	`getChanged()` Returns changed elements.
`java.util.Map`	`getRemoved()` Returns removed elements.
`boolean`	`hasChangedSinceTagging()` Returns if the content of the object has changed since setting the tag.
`boolean`	`isChanged()` Returns if the list has changed.
`boolean`	`isEmpty()`
`boolean`	`isTagged()` Returns if the object is currently tagged.
`java.util.Set`	`keySet()`
`java.lang.Object`	`put(java.lang.Object key, java.lang.Object newValue)`
`void`	`putAll(java.util.Map newMap)`
`java.lang.Object`	`remove(java.lang.Object key)`
`void`	`revert()` Roll back all changes made since construction.
`void`	`revertToTag()` Reverts all changes made since setting the tag and clears internal state.
`int`	`size()`
`void`	`tag()` Start memorizing changes.
`java.lang.String`	`toString()`
`void`	`untag()` Stop memorizing changes and clear internal state.
`java.util.Collection`	`values()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map
compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

- Constructor Detail
  - ChangeTrackingMap
```
public ChangeTrackingMap(java.util.Map map)
```
    Constructor with covered map. The map is tagged at construction time - This means isTagged() will return true without calling tag() first. If this behavior is not wanted you can call untag() after constructing the map.
    
    Parameters:
    
    map - Wrapped map - Be aware that this map will be changed by this class. There is no internal copy of the map - The reference itself is used.
- Method Detail
  - isChanged
```
public final boolean isChanged()
```
    Returns if the list has changed. If the map is not in tag mode (this means isTagged() returns true) this method will always return false.
    
    Returns:
    
    If elements have been added or deleted true else false.
  - getRemoved
```
public final java.util.Map getRemoved()
```
    Returns removed elements. If the map is not in tag mode (this means isTagged() returns true) this method will always return an empty map.
    
    Returns:
    
    Elements that have been deleted since construction of this instance - Unmodifiable map!
  - getChanged
```
public final java.util.Map getChanged()
```
    Returns changed elements. If the map is not in tag mode (this means isTagged() returns true) this method will always return an empty map.
    
    Returns:
    
    Elements that have been changed since construction of this instance - Unmodifiable map!
  - revert
```
public final void revert()
```
    Roll back all changes made since construction. This is the same function ad revertToTag(). If the map is not in tag mode ( this means isTagged() returns true) this method will do nothing.
  - getAdded
```
public final java.util.Map getAdded()
```
    Returns added elements. If the map is not in tag mode (this means isTagged() returns true) this method will always return an empty map.
    
    Returns:
    
    Elements that have been added since construction of this instance - Unmodifiable map!
  - clear
```
public final void clear()
```
    Specified by:
    
    clear in interface java.util.Map
  - containsKey
```
public final boolean containsKey(java.lang.Object key)
```
    Specified by:
    
    containsKey in interface java.util.Map
  - containsValue
```
public final boolean containsValue(java.lang.Object value)
```
    Specified by:
    
    containsValue in interface java.util.Map
  - entrySet
```
public final java.util.Set entrySet()
```
    Specified by:
    
    entrySet in interface java.util.Map
  - get
```
public final java.lang.Object get(java.lang.Object key)
```
    Specified by:
    
    get in interface java.util.Map
  - isEmpty
```
public final boolean isEmpty()
```
    Specified by:
    
    isEmpty in interface java.util.Map
  - keySet
```
public final java.util.Set keySet()
```
    Specified by:
    
    keySet in interface java.util.Map
  - put
```
public final java.lang.Object put(java.lang.Object key,
                                  java.lang.Object newValue)
```
    Specified by:
    
    put in interface java.util.Map
  - putAll
```
public final void putAll(java.util.Map newMap)
```
    Specified by:
    
    putAll in interface java.util.Map
  - remove
```
public final java.lang.Object remove(java.lang.Object key)
```
    Specified by:
    
    remove in interface java.util.Map
  - size
```
public final int size()
```
    Specified by:
    
    size in interface java.util.Map
  - values
```
public final java.util.Collection values()
```
    Specified by:
    
    values in interface java.util.Map
  - toString
```
public final java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object
  - hasChangedSinceTagging
```
public final boolean hasChangedSinceTagging()
```
    Returns if the content of the object has changed since setting the tag.
    
    Specified by:
    
    hasChangedSinceTagging in interface Taggable
    
    Returns:
    
    If something has changed true else false.
  - isTagged
```
public final boolean isTagged()
```
    Returns if the object is currently tagged.
    
    Specified by:
    
    isTagged in interface Taggable
    
    Returns:
    
    If a tag is set true else false.
  - revertToTag
```
public final void revertToTag()
```
    Reverts all changes made since setting the tag and clears internal state.
    
    Specified by:
    
    revertToTag in interface Taggable
  - tag
```
public final void tag()
```
    Start memorizing changes.
    
    Specified by:
    
    tag in interface Taggable
  - untag
```
public final void untag()
```
    Stop memorizing changes and clear internal state. It's not reverting any change! It's simply a "forget all changes".
    
    Specified by:
    
    untag in interface Taggable

Class ChangeTrackingMap

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.Map

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.Map

Constructor Detail

ChangeTrackingMap

Method Detail

isChanged

getRemoved

getChanged

revert

getAdded

clear

containsKey

containsValue

entrySet

get

isEmpty

keySet

put

putAll

remove

size

values

toString

hasChangedSinceTagging

isTagged

revertToTag

tag

untag