Indexer (S-Space Package 2.0.1 API)

All Superinterfaces:

Iterable<Map.Entry<T,Integer>>

All Known Implementing Classes:

HashIndexer, ObjectIndexer, TypedIsomorphicGraphIndexer
```
public interface Indexer<T>
extends Iterable<Map.Entry<T,Integer>>
```
A utility class for mapping a set of objects to unique indices. The indices returned by this class will always being at 0.

See Also:
Counter

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`clear()` Removes all of the item-index mappings.
`boolean`	`contains(T item)` Returns `true` if the item has a corresponding index
`int`	`find(T item)` Returns the index for the item or a negative value corresponding to the index the object would have been assigned if it had been added.
`int`	`highestIndex()` Returns the highest index to which any element is mapped.
`int`	`index(T item)` Adds the item and creates an index for it, returning that index.
`boolean`	`indexAll(Collection<T> items)` Adds an index for each item in the collection if it did not already exist, returning `true` if at least one new index was added.
`Set<T>`	`items()` Returns an unmodifiable view of the items currently mapped to indices
`Iterator<Map.Entry<T,Integer>>`	`iterator()` Returns an iterator over all the objects and their corresponding indices.
`T`	`lookup(int index)` Returns the element to which this index is mapped or `null` if the index has not been mapped
`Map<Integer,T>`	`mapping()` Returns an unmodifiable view from each index to the object mapped to that index.
`int`	`size()` Returns the number of items that are mapped to indices.

- Method Detail
  - index
```
int index(T item)
```
    Adds the item and creates an index for it, returning that index.
  - indexAll
```
boolean indexAll(Collection<T> items)
```
    Adds an index for each item in the collection if it did not already exist, returning true if at least one new index was added.
  - clear
```
void clear()
```
    Removes all of the item-index mappings.
  - contains
```
boolean contains(T item)
```
    Returns true if the item has a corresponding index
  - items
```
Set<T> items()
```
    Returns an unmodifiable view of the items currently mapped to indices
  - find
```
int find(T item)
```
    Returns the index for the item or a negative value corresponding to the index the object would have been assigned if it had been added.
  - highestIndex
```
int highestIndex()
```
    Returns the highest index to which any element is mapped.
  - iterator
```
Iterator<Map.Entry<T,Integer>> iterator()
```
    Returns an iterator over all the objects and their corresponding indices. The returned iterator does not support remove.
    
    Specified by:
    
    iterator in interface Iterable<Map.Entry<T,Integer>>
  - lookup
```
T lookup(int index)
```
    Returns the element to which this index is mapped or null if the index has not been mapped
  - mapping
```
Map<Integer,T> mapping()
```
    Returns an unmodifiable view from each index to the object mapped to that index.
  - size
```
int size()
```
    Returns the number of items that are mapped to indices.

Interface Indexer<T>

Method Summary

Method Detail

index

indexAll

clear

contains

items

find

highestIndex

iterator

lookup

mapping

size