com.partnersoft.io
Class SequentialIterableInput<T>

java.lang.Object
  com.partnersoft.io.AbstractIterableInput<T>
      com.partnersoft.io.SequentialIterableInput<T>

Type Parameters:

T -

All Implemented Interfaces:

IterableInput<T>, java.lang.Iterable<T>

Direct Known Subclasses:

SequentialRoverBytesInput

public class SequentialIterableInput<T>
extends AbstractIterableInput<T>

A sequential aggregator of IterableInputs. Goes through them in order; handles closings on all at the same time.

Copyright 2009 Partner Software, Inc.

Version:

$Id$

Author:

Paul Reavis

Nested Class Summary

Nested classes/interfaces inherited from interface com.partnersoft.io.IterableInput

IterableInput.Status

Constructor Summary

SequentialIterableInput(java.lang.Iterable<IterableInput<T>> inputs)

SequentialIterableInput(IterableInput<T>... inputs)

Method Summary

protected void	closeImp() Subclass implementation of guts of close() method.
protected boolean	fetchImp() Subclass implementation of guts of fetch() method.
T	getFetched() Returns the last fetched item (if immutable) or a copy of it (if mutable).
protected void	openImp() Subclass implementation of guts of open() method.

Methods inherited from class com.partnersoft.io.AbstractIterableInput

close, fetch, getException, getStatus, isFetchValid, iterator, open

Methods inherited from class java.lang.Object

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

Constructor Detail

SequentialIterableInput

public SequentialIterableInput(java.lang.Iterable<IterableInput<T>> inputs)

SequentialIterableInput

public SequentialIterableInput(IterableInput<T>... inputs)

Method Detail

openImp

protected void openImp()
                throws java.lang.Exception

Description copied from class: AbstractIterableInput

Subclass implementation of guts of open() method.

Subclasses must implement this to do the actual work required by open(). Feel free to throw exceptions; these are caught inside the open() itself and applied to the exception variable. Thus, you can focus on the actual task instead of paperwork.

Specified by:

openImp in class AbstractIterableInput<T>

Throws:

java.lang.Exception

closeImp

protected void closeImp()
                 throws java.lang.Exception

Description copied from class: AbstractIterableInput

Subclass implementation of guts of close() method.

Subclasses must implement this to do the actual work required by close(). Feel free to throw exceptions; these are caught inside the close() itself and applied to the exception variable. Thus, you can focus on the actual task instead of paperwork.

Specified by:

closeImp in class AbstractIterableInput<T>

Throws:

java.lang.Exception

fetchImp

protected boolean fetchImp()
                    throws java.lang.Exception

Description copied from class: AbstractIterableInput

Subclass implementation of guts of fetch() method.

Subclasses must implement this to do the actual work required by fetch(). Feel free to throw exceptions; these are caught inside the fetch() itself and applied to the exception variable. Thus, you can focus on the actual task instead of paperwork.

Specified by:

fetchImp in class AbstractIterableInput<T>

Returns:

true if fetch successful

Throws:

java.lang.Exception

getFetched

public T getFetched()

Description copied from interface: IterableInput

Returns the last fetched item (if immutable) or a copy of it (if mutable). Note that this means multiple calls to getFetched() may return different objects for the same fetch, but that the return value is always safe to share since modifying it won't affect the IterableInput's internal state.

The last fetched item is that loaded by the most recent call to fetch().

Implementations may prefer to instantiate this lazily; in other words, the underlying IterableInput may know that it has a valid fetch (e.g. loaded the characters for a String into an internal buffer) but may not have created this object yet (e.g. created a new String with the characters from the buffer). This allows skipping items without instantiating them, or accessing the underlying state without instantiating an actual item.

Implementations may also wish to provide unsafe access to the fetched item via other methods or public variables. The requirement that a safe copy be returned does prevent object reuse or other optimizations with this method, so feel free to use other means to provide a high-performance alternative.

This method may only be called when the input is in the FETCHING status. Calling it from any other status will result in an IllegalStateException.

Returns:

object representing the most recent fetch