aQute.lib.persistentmap

Class PersistentMap<V>

java.lang.Object

java.util.AbstractMap<java.lang.String,V>

aQute.lib.persistentmap.PersistentMap<V>

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, java.util.Map<java.lang.String,V>

public class PersistentMap<V>
extends java.util.AbstractMap<java.lang.String,V>
implements java.io.Closeable

Implements a low performance but easy to use map that is backed on a directory. All objects are stored as JSON objects and therefore should be DTOs. Each key is a file name and the contents is the value encoded in JSON. The PersistentMap will attempt to lock the directory. This is a non-concurrent implementation so you must ensure it is only used in a single thread. It cannot of course also not share the data directory.

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

java.util.AbstractMap.SimpleEntry<K,V>, java.util.AbstractMap.SimpleImmutableEntry<K,V>

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

java.util.Map.Entry<K,V>

Field Summary

Fields

Modifier and Type	Field and Description
(package private) java.util.Map<java.lang.String,java.lang.ref.SoftReference<V>>	cache
(package private) boolean	closed
(package private) static JSONCodec	codec
(package private) java.io.File	data
(package private) java.io.File	dir
(package private) boolean	inited
(package private) java.io.RandomAccessFile	lockFile
(package private) java.lang.reflect.Type	type

Constructor Summary

Constructors

Constructor and Description
PersistentMap(java.io.File dir, java.lang.Class<V> type)
PersistentMap(java.io.File dir, java.lang.Class<V> type, java.util.Map<java.lang.String,V> map)
PersistentMap(java.io.File dir, java.lang.reflect.Type type)
PersistentMap(java.io.File dir, java.lang.reflect.Type type, java.util.Map<java.lang.String,V> map)

Method Summary

Modifier and Type	Method and Description
void	clear()
void	clear(long whenOlder)
void	close()
java.util.Set<java.util.Map.Entry<java.lang.String,V>>	entrySet()
(package private) void	init()
java.util.Set<java.lang.String>	keySet()
private java.nio.channels.FileLock	lock()
V	put(java.lang.String key, V value)
V	remove(java.lang.String key)
java.lang.String	toString()
private void	unlock(java.nio.channels.FileLock lock)

Methods inherited from class java.util.AbstractMap

clone, containsKey, containsValue, equals, get, hashCode, isEmpty, putAll, remove, size, values

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, forEach, getOrDefault, merge, putIfAbsent, remove, replace, replace, replaceAll

Field Detail

codec

static final JSONCodec codec

dir

final java.io.File dir

data

final java.io.File data

lockFile

final java.io.RandomAccessFile lockFile

cache

final java.util.Map<java.lang.String,java.lang.ref.SoftReference<V>> cache

inited

boolean inited

closed

boolean closed

type

java.lang.reflect.Type type

Constructor Detail

PersistentMap

public PersistentMap(java.io.File dir,
                     java.lang.reflect.Type type)
              throws java.lang.Exception

Throws:

java.lang.Exception

PersistentMap

public PersistentMap(java.io.File dir,
                     java.lang.Class<V> type)
              throws java.lang.Exception

Throws:

java.lang.Exception

PersistentMap

public PersistentMap(java.io.File dir,
                     java.lang.Class<V> type,
                     java.util.Map<java.lang.String,V> map)
              throws java.lang.Exception

Throws:

java.lang.Exception

PersistentMap

public PersistentMap(java.io.File dir,
                     java.lang.reflect.Type type,
                     java.util.Map<java.lang.String,V> map)
              throws java.lang.Exception

Throws:

java.lang.Exception

Method Detail

init

void init()

entrySet

public java.util.Set<java.util.Map.Entry<java.lang.String,V>> entrySet()

Specified by:

entrySet in interface java.util.Map<java.lang.String,V>

Specified by:

entrySet in class java.util.AbstractMap<java.lang.String,V>

put

public V put(java.lang.String key,
             V value)

Specified by:

put in interface java.util.Map<java.lang.String,V>

Overrides:

put in class java.util.AbstractMap<java.lang.String,V>

lock

private java.nio.channels.FileLock lock()
                                 throws java.io.IOException,
                                        java.lang.InterruptedException

Throws:

java.io.IOException

java.lang.InterruptedException

unlock

private void unlock(java.nio.channels.FileLock lock)
             throws java.io.IOException

Throws:

java.io.IOException

remove

public V remove(java.lang.String key)

clear

public void clear()

Specified by:

clear in interface java.util.Map<java.lang.String,V>

Overrides:

clear in class java.util.AbstractMap<java.lang.String,V>

keySet

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

Specified by:

keySet in interface java.util.Map<java.lang.String,V>

Overrides:

keySet in class java.util.AbstractMap<java.lang.String,V>

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Throws:

java.io.IOException

toString

public java.lang.String toString()

Overrides:

toString in class java.util.AbstractMap<java.lang.String,V>

clear

public void clear(long whenOlder)