Cache (Apache Ant API)
Date: 2018-09-12

Package org.apache.tools.ant.types.selectors.modifiedselector

## Interface Cache

- All Known Implementing Classes:
    `PropertiesfileCache`

      public interface Cache

  A Cache let the user store key-value-pairs in a permanent manner and access them. It is possible that a client uses get() before load() therefore the implementation must ensure that no error occurred because of the wrong order. The implementing class should implement a useful toString() method.
  Since:
    Ant 1.6
  Version:
    2003-09-13

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `void` | `delete()` | Deletes the cache.
    `java.lang.Object` | `get​(java.lang.Object key)` | Returns a value for a given key from the cache.
    `boolean` | `isValid()` | Checks its prerequisites.
    `java.util.Iterator<java.lang.String>` | `iterator()` | Returns an iterator over the keys in the cache.
    `void` | `load()` | Loads the cache, must handle not existing cache.
    `void` | `put​(java.lang.Object key, java.lang.Object value)` | Saves a key-value-pair in the cache.
    `void` | `save()` | Saves modification of the cache.

- - ### Method Detail

    - #### isValid

          boolean isValid()

      Checks its prerequisites.
      Returns:
        true if all is ok, otherwise false.

    - #### delete

          void delete()

      Deletes the cache. If file based the file has to be deleted also.

    - #### load

          void load()

      Loads the cache, must handle not existing cache.

    - #### save

          void save()

      Saves modification of the cache.

    - #### get

          java.lang.Object get​(java.lang.Object key)

      Returns a value for a given key from the cache.
      Parameters:
        `key` - the key
      Returns:
        the stored value

    - #### put

          void put​(java.lang.Object key,
                   java.lang.Object value)

      Saves a key-value-pair in the cache.
      Parameters:
        `key` - the key
        `value` - the value

    - #### iterator

          java.util.Iterator<java.lang.String> iterator()

      Returns an iterator over the keys in the cache.
      Returns:
        An iterator over the keys.