FilePersistence<T>

Abstract persistence component that stores data in flat files and caches them in memory.

Description

The FilePersistence class allows you to create persistence components that store data in flat files and chache them in memory.

Important points

This is the most basic persistence component that is only able to store data items of any type.
Specific CRUD operations over the data items must be implemented in child classes by accessing the self._items property and calling the save method.

Configuration parameters

path: path to the file where data is stored

References

*:logger:*:*:1.0 - (optional) ILogger components to pass log messages

Constructors

Creates a new instance of the file persistence component.

public FilePersistence(Class type, JsonFilePersister persister)

persister: JsonFilePersister - (optional) persister component that loads and saves data from/to a flat file.

Instance methods

configure

Configures the component by passing its configuration parameters.

public void configure(ConfigParams config) config) throws ConfigException

config: ConfigParams - configuration parameters to be set.

Examples

 {@code
  class MyJsonFilePersistence extends FilePersistence<MyData> {
    public MyJsonFilePersistence(String path) {
      super(MyData.class, new JsonFilePersister(path));
    }
  
    public MyData getByName(IContext context, String name) {
      MyData item = find(name); // search method
      ...
      return item;
    } 
  
    public MyData set(IContext context, MyData item) {
      this._items = filter(); // filter method
      ...
      this._items.add(item);
      this.save(context);
    }
  
  }
  }