StateStoreData (MadgikCommons 1.5.1-SNAPSHOT API)

java.lang.Object
- gr.uoa.di.madgik.commons.state.store.data.StateStoreData

```
public class StateStoreData
extends Object
```
Class responsible of handling the persistency and retrieval of the actual state data clients want to persiste with the State Store Repository. This class dows not keep any internal state and is instanciated every time a new operation needs to be perofrmed on the repository payload data. The operations this class provides are not thread safe and even though it represents a shared resource it does not provide any kind of of resource locking policy. This is left to the wrapping class, StateManager. This class needs a value kith key EncodingCharset in the ConfigurationManager representing the charaset name to use during alphanumeric storage and retrieval through Put(gr.uoa.di.madgik.commons.state.store.registry.StateStoreRegistryKey, java.lang.String) and GetAlphanumeric(gr.uoa.di.madgik.commons.state.store.registry.StateStoreRegistryKey)

Author:

gpapanikos

Constructor Summary

Constructors
Constructor and Description

StateStoreData(StateStoreInfo Info)
Creates a new instance

Constructors
Constructor and Description
`StateStoreData(StateStoreInfo Info)` Creates a new instance

Method Summary

Methods
Modifier and Type	Method and Description
`String`	`GetAlphanumeric(StateStoreRegistryKey Key)` Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
`byte[]`	`GetByteArray(StateStoreRegistryKey Key)` Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
`File`	`GetFile(StateStoreRegistryKey Key)` Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
`ISerializable`	`GetISerializable(StateStoreRegistryKey Key)` Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
`Serializable`	`GetSerializable(StateStoreRegistryKey Key)` Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
`File`	`MoveToClean(Map<String,StateStoreRegistryKey> registry)` In case of deletes and updates in the registry and data file, there will be data kept in the file that are no longer needed but simply remain increrasing the size of the repository files.
`void`	`Put(StateStoreRegistryKey Key, byte[] bytearray)` Appends the provided payload to the repository data file.
`void`	`Put(StateStoreRegistryKey Key, File file)` Appends the provided payload to the repository data file.
`void`	`Put(StateStoreRegistryKey Key, ISerializable obj)` Appends the provided payload to the repository data file.
`void`	`Put(StateStoreRegistryKey Key, Serializable obj)` Appends the provided payload to the repository data file.
`void`	`Put(StateStoreRegistryKey Key, String Alphanumeric)` Appends the provided payload to the repository data file.

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

- Constructor Detail
  - StateStoreData
```
public StateStoreData(StateStoreInfo Info)
```
    Creates a new instance
    
    Parameters:
    Info - The repository persistency files information
- Method Detail
  - Put
```
public void Put(StateStoreRegistryKey Key,
       String Alphanumeric)
         throws Exception
```
    Appends the provided payload to the repository data file. The provided metadata StateStoreRegistryKey entry is updated with the offsets of the stored data
    
    Parameters:
    Key - The metadata entry representing the data.
    Alphanumeric - The payload to store as a sequence of bytes using the configuration value with key EncodingCharset from the ConfigurationManager
    
    Throws:
    
    Exception - the store could not be performed
  - GetAlphanumeric
```
public String GetAlphanumeric(StateStoreRegistryKey Key)
                       throws Exception
```
    Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
    
    Parameters:
    Key - The metadate entry referencing the data to retrieve
    
    Returns:
    The payload after decoding it using the value with key EncodingCharset from the ConfigurationManager back to a string from a byte array
    
    Throws:
    
    Exception - The retrieval could not be performed
  - Put
```
public void Put(StateStoreRegistryKey Key,
       byte[] bytearray)
         throws Exception
```
    Appends the provided payload to the repository data file. The provided metadata StateStoreRegistryKey entry is updated with the offsets of the stored data
    
    Parameters:
    Key - The metadata entry representing the data.
    bytearray - The payload to store as a sequence of bytes
    
    Throws:
    
    Exception - The store could not be performed
  - GetByteArray
```
public byte[] GetByteArray(StateStoreRegistryKey Key)
                    throws Exception
```
    Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
    
    Parameters:
    Key - The metadate entry referencing the data to retrieve
    
    Returns:
    The payload
    
    Throws:
    
    Exception - The retrieval could not be performed
  - Put
```
public void Put(StateStoreRegistryKey Key,
       ISerializable obj)
         throws Exception
```
    Appends the provided payload to the repository data file. The provided metadata StateStoreRegistryKey entry is updated with the offsets of the stored data
    
    Parameters:
    Key - The metadata entry representing the data.
    obj - The object to store serializing it through ISerializable.Serialize()
    
    Throws:
    
    Exception - The store could not be performed
  - GetISerializable
```
public ISerializable GetISerializable(StateStoreRegistryKey Key)
                               throws Exception
```
    Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
    
    Parameters:
    Key - The metadate entry referencing the data to retrieve
    
    Returns:
    The object instantiated with its default constructor and populated through the ISerializable.Deserialize(byte[])
    
    Throws:
    
    Exception - The retrieval could not be performed
  - Put
```
public void Put(StateStoreRegistryKey Key,
       Serializable obj)
         throws Exception
```
    Appends the provided payload to the repository data file. The provided metadata StateStoreRegistryKey entry is updated with the offsets of the stored data
    
    Parameters:
    Key - The metadata entry representing the data.
    obj - The object to store serializing it through an ObjectOutputStream
    
    Throws:
    
    Exception - The store could not be performed
  - GetSerializable
```
public Serializable GetSerializable(StateStoreRegistryKey Key)
                             throws Exception
```
    Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
    
    Parameters:
    Key - The metadate entry referencing the data to retrieve
    
    Returns:
    The object retrieved using an ObjectInputStream
    
    Throws:
    
    Exception - The retrieval could not be performed
  - Put
```
public void Put(StateStoreRegistryKey Key,
       File file)
         throws Exception
```
    Appends the provided payload to the repository data file. The provided metadata StateStoreRegistryKey entry is updated with the offsets of the stored data
    
    Parameters:
    Key - The metadata entry representing the data.
    file - The file whose payload to retrieve and store
    
    Throws:
    
    Exception - The store could not be performed
  - GetFile
```
public File GetFile(StateStoreRegistryKey Key)
             throws Exception
```
    Retrieves the actual payload referenced by the provided metadata entry and returns it as the expected type.
    
    Parameters:
    Key - The metadate entry referencing the data to retrieve
    
    Returns:
    The temporary file created where the payload is stored as it is retrieved by the repository data file
    
    Throws:
    
    Exception - The retrieval could not be performed
  - MoveToClean
```
public File MoveToClean(Map<String,StateStoreRegistryKey> registry)
                 throws Exception
```
    In case of deletes and updates in the registry and data file, there will be data kept in the file that are no longer needed but simply remain increrasing the size of the repository files. This method reorganizes the data file into a new temporary file it creates that holds only the needed valid data records. During the process each entry that is valid as provided by the caller it is persisted in the new clean file. The metadata entries provided are also updated to point to the new offsets where their respective data are stored. This leaves the registry part of the repository in an inconsistend state until the file that the StateStoreInfo points to as the data repository file is deleted and replaced with the file that this method returns
    
    Parameters:
    registry - the in memeory structure holding the entries that should be kept from the data file
    
    Returns:
    The file created holding the new clean file to be used as the repository data file
    
    Throws:
    
    Exception - The clean operation could not be performed

Class StateStoreData

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

StateStoreData

Method Detail

Put

GetAlphanumeric

Put

GetByteArray

Put

GetISerializable

Put

GetSerializable

Put

GetFile

MoveToClean