dk.netarkivet.common.utils
Class FileArrayIterator<T>

java.lang.Object
  dk.netarkivet.common.utils.FilterIterator<java.io.File,T>
      dk.netarkivet.common.utils.FileArrayIterator<T>

Type Parameters:

T - The type returned by the FileArrayIterator

All Implemented Interfaces:

java.util.Iterator<T>

public abstract class FileArrayIterator<T>
extends FilterIterator<java.io.File,T>

An iterator that iterates over elements that can be read from files, given an array of files. It is robust against disappearing files, but does not try to find new ones that appear while iterating. It keeps the Iterator contract that next() returns an element if hasNext() returned true since last next(). This may mean that the underlying file has disappeared by the time next() is called, but the object is returned anyway.

Constructor Summary

protected

FileArrayIterator(java.io.File[] files)

Method Summary

protected T	filter(java.io.File f) Returns the T object corresponding to the given file, or null if that object is to be skipped.
protected abstract T	getNext(java.io.File file) Gives an object created from the given file, or null.

Methods inherited from class dk.netarkivet.common.utils.FilterIterator

hasNext, next, remove

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FileArrayIterator

protected FileArrayIterator(java.io.File[] files)

Method Detail

filter

protected T filter(java.io.File f)

Returns the T object corresponding to the given file, or null if that object is to be skipped.

Specified by:

filter in class FilterIterator<java.io.File,T>

Parameters:

f - A given file

Returns:

An object in the T domain, or null

getNext

protected abstract T getNext(java.io.File file)

Gives an object created from the given file, or null.

Parameters:

file - The file to read

Returns:

An object of the type iterated over by the list, or null if the file does not exist or cannot be used to create an appropriate object.