com.inductiveautomation.ignition.common

Class PersistentProperties

java.lang.Object

java.util.Dictionary<K,V>

java.util.Hashtable<java.lang.Object,java.lang.Object>

java.util.Properties

com.inductiveautomation.ignition.common.PersistentProperties

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.util.Map<java.lang.Object,java.lang.Object>

public class PersistentProperties
extends java.util.Properties

A simple extension of properties that is meant to represent a file based property file. The entire property file will be written eventually after a call to setProperty(), according to the max storage frequency.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	_savePaused
protected int	maxStorageFrequencyMS
protected boolean	writeQueued
protected java.lang.Thread	writeThread

Fields inherited from class java.util.Properties

defaults

Constructor Summary

Constructors

Constructor and Description
PersistentProperties()
PersistentProperties(java.io.File file, java.lang.String comments)
PersistentProperties(java.io.File file, java.lang.String comments, boolean requireInitial) Creates a new PersistentProperties object.

Method Summary

Modifier and Type	Method and Description
protected void	copyFile(java.io.File source, java.io.File dest)
java.io.File	getFile()
int	getMaxStorageFrequencyMS() Returns the maximum rate at which the file will be written.
java.io.File	getTempFile()
boolean	isNew()
java.util.Set<java.lang.Object>	keySet()
protected void	potentiallyExecuteWrite()
java.lang.Object	remove(java.lang.Object key)
java.lang.Object	removeIntermediate(java.lang.Object key)
void	setMaxStorageFrequencyMS(int maxStorageFrequencyMS) Sets the maximum rate at which the file will be written.
java.lang.Object	setProperty(java.lang.String key, java.lang.String value)
java.lang.Object	setPropertyIntermediate(java.lang.String key, java.lang.String value) Sets a property without pesisting the change.
void	storeChanges() Do the following to ensure there is always a well-formed file on the HD Write file to temp file Copy temp file to main file
protected void	tryLoad(java.io.File file) Tries to call super.loadFromXML with an input stream from this file.

Methods inherited from class java.util.Properties

getProperty, getProperty, list, list, load, load, loadFromXML, propertyNames, save, store, store, storeToXML, storeToXML, stringPropertyNames

Methods inherited from class java.util.Hashtable

clear, clone, compute, computeIfAbsent, computeIfPresent, contains, containsKey, containsValue, elements, entrySet, equals, forEach, get, getOrDefault, hashCode, isEmpty, keys, merge, put, putAll, putIfAbsent, rehash, remove, replace, replace, replaceAll, size, toString, values

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

_savePaused

protected transient boolean _savePaused

maxStorageFrequencyMS

protected int maxStorageFrequencyMS

writeThread

protected transient java.lang.Thread writeThread

writeQueued

protected transient boolean writeQueued

Constructor Detail

PersistentProperties

public PersistentProperties(java.io.File file,
                            java.lang.String comments)
                     throws java.io.IOException

Throws:

java.io.IOException

PersistentProperties

public PersistentProperties(java.io.File file,
                            java.lang.String comments,
                            boolean requireInitial)
                     throws java.io.IOException

Creates a new PersistentProperties object. The backup file will be "."+filename+".bak" and the clean file will be filename+"_clean".

Parameters:

requireInitial - Whether or not a valid file or _clean file is required. If false, the constructor will accept the situation where none of the 3 files exist.

Throws:

java.io.IOException

PersistentProperties

public PersistentProperties()

Method Detail

getMaxStorageFrequencyMS

public int getMaxStorageFrequencyMS()

Returns the maximum rate at which the file will be written. After a property is set, the file is written immediately, unless the specified time has not passed, in which case the file will be marked as "dirty" and written when the delay expires.

Defaults to 500ms.

setMaxStorageFrequencyMS

public void setMaxStorageFrequencyMS(int maxStorageFrequencyMS)

Sets the maximum rate at which the file will be written. If 0, writes will occur immediately, and in the same thread, instead of asynchronously.

isNew

public boolean isNew()

getFile

public java.io.File getFile()

getTempFile

public java.io.File getTempFile()

tryLoad

protected void tryLoad(java.io.File file)
                throws java.io.IOException

Tries to call super.loadFromXML with an input stream from this file.

Throws:

java.io.IOException - if anything goes wrong with the load.

removeIntermediate

public java.lang.Object removeIntermediate(java.lang.Object key)

remove

public java.lang.Object remove(java.lang.Object key)

Specified by:

remove in interface java.util.Map<java.lang.Object,java.lang.Object>

Overrides:

remove in class java.util.Hashtable<java.lang.Object,java.lang.Object>

setProperty

public java.lang.Object setProperty(java.lang.String key,
                                    java.lang.String value)

Overrides:

setProperty in class java.util.Properties

setPropertyIntermediate

public java.lang.Object setPropertyIntermediate(java.lang.String key,
                                                java.lang.String value)

Sets a property without pesisting the change.

keySet

public java.util.Set<java.lang.Object> keySet()

Specified by:

keySet in interface java.util.Map<java.lang.Object,java.lang.Object>

Overrides:

keySet in class java.util.Hashtable<java.lang.Object,java.lang.Object>

storeChanges

public void storeChanges()

Do the following to ensure there is always a well-formed file on the HD

1. Write file to temp file
2. Copy temp file to main file

potentiallyExecuteWrite

protected void potentiallyExecuteWrite()

copyFile

protected void copyFile(java.io.File source,
                        java.io.File dest)
                 throws java.io.IOException

Throws:

java.io.IOException