All Known Subinterfaces:

NotCachablePersistenceManager

All Known Implementing Classes:

FilePersistenceManager
```
@ConsumerType
public interface PersistenceManager
```
The PersistenceManager interface defines the API to be implemented to support persisting configuration data. This interface may be implemented by bundles, which support storing configuration data in different locations.
The Apache Felix Configuration Admin Service bundles provides an implementation of this interface using the platform file system to store configuration data.
Implementations of this interface must support loading and storing java.util.Dictionary objects as defined in section 104.4.2, Configuration Properties, of the Configuration Admin Service Specification Version 1.2.
To make implementations of this interface available to the Configuration Admin Service they must be registered as service for this interface. The Configuration Admin Service will consider all registered services plus the default platform file system based implementation to load configuration data. To store new configuration data, the persistence manager service with the highest rank value - the service.ranking service property - is used. If no persistence manager service has been registered, the platform file system based implementation is used.

Field Summary

Fields
Modifier and Type Field Description

static String PROPERTY_NAME
Service registration property to define a unique name for the persistence manager.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`delete(String pid)`	Removes the `Dictionary` for the given `pid`.
`boolean`	`exists(String pid)`	Returns `true` if a persisted `Dictionary` exists for the given `pid`.
`Enumeration`	`getDictionaries()`	Returns an enumeration of all `Dictionary` objects known to this persistence manager.
`Dictionary`	`load(String pid)`	Returns the `Dictionary` for the given `pid`.
`void`	`store(String pid, Dictionary properties)`	Stores the `Dictionary` under the given `pid`.

- Field Detail
  - PROPERTY_NAME
```
static final String PROPERTY_NAME
```
    Service registration property to define a unique name for the persistence manager.
    
    Since:
    
    1.2
    
    See Also:
    
    Constant Field Values
- Method Detail
  - exists
```
boolean exists(String pid)
```
    Returns true if a persisted Dictionary exists for the given pid.
    
    Parameters:
    
    pid - The identifier for the dictionary to test.
    
    Returns:
    
    true if a persisted dictionary exists for the pid.
  - load
```
Dictionary load(String pid)
         throws IOException
```
    Returns the Dictionary for the given pid.
    Implementations are expected to return dictionary instances which may be modified by the caller without affecting any underlying data or affecting future calls to this method with the same PID. In other words the reference equation load(pid) != load(pid) must hold true.
    
    Parameters:
    
    pid - The identifier for the dictionary to load.
    
    Returns:
    
    The dictionary for the identifier. This must not be null but may be empty.
    
    Throws:
    
    IOException - If an error occurs loading the dictionary. An IOException must also be thrown if no dictionary exists for the given identifier.
  - getDictionaries
```
Enumeration getDictionaries()
                     throws IOException
```
    Returns an enumeration of all Dictionary objects known to this persistence manager.
    Implementations of this method are allowed to return lazy enumerations. That is, it is allowable for the enumeration to not return a dictionary if loading it results in an error.
    Implementations are expected to return dictionary instances which may be modified by the caller without affecting any underlying data or affecting future calls to this method.
    The Enumeration returned from this method must be stable against concurrent calls to either of the load(String), store(String, Dictionary), and delete(String) methods.
    
    Returns:
    
    A possibly empty Enumeration of all dictionaries.
    
    Throws:
    
    IOException - If an error occurs getting the dictionaries.
  - store
```
void store(String pid,
           Dictionary properties)
    throws IOException
```
    Stores the Dictionary under the given pid.
    The dictionary provided to this method must be considered private to the caller. Any modification by the caller after this method finishes must not influence any internal storage of the provided data. Implementations must not modify the dictionary.
    
    Parameters:
    
    pid - The identifier of the dictionary.
    
    properties - The Dictionary to store.
    
    Throws:
    
    IOException - If an error occurs storing the dictionary. If this exception is thrown, it is expected, that exists(pid returns false.
  - delete
```
void delete(String pid)
     throws IOException
```
    Removes the Dictionary for the given pid. If such a dictionary does not exist, this method has no effect.
    
    Parameters:
    
    pid - The identifier of the dictionary to delete.
    
    Throws:
    
    IOException - If an error occurs deleting the dictionary. This exception must not be thrown if no dictionary with the given identifier exists.

Interface PersistenceManager

Field Summary

Method Summary

Field Detail

PROPERTY_NAME

Method Detail

exists

load

getDictionaries

store

delete