Package convex.core.data

Class ADataStructure<E extends ACell>

java.lang.Object

convex.core.data.AObject

convex.core.data.ACell

convex.core.data.ACountable<E>

convex.core.data.ADataStructure<E>

Type Parameters:

E - Type of Data Structure elements

All Implemented Interfaces:

IValidated, IWriteable

Direct Known Subclasses:

ACollection, AMap

public abstract class ADataStructure<E extends ACell>
extends ACountable<E>

Abstract base class for Persistent data structures. Each can be regarded as a countable, immutable collection of elements. Data structures in general support:

• Immutability
• Addition of an element(s) of appropriate type
• Construction of an empty (zero) element

"When you know your data can never change out from underneath you, everything is different." - Rich Hickey

Field Summary

Fields

Modifier and Type	Field	Description
protected final long	count

Fields inherited from class convex.core.data.ACell

cachedRef, memorySize

Fields inherited from class convex.core.data.AObject

encoding

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ADataStructure(long count)

Method Summary

Modifier and Type	Method	Description
abstract ADataStructure<E>	assoc(ACell key, ACell value)	Associates a key with a value in this associative data structure.
final void	checkIndex(long ix)	Checks if the given index is in range for this data structure
abstract ADataStructure<E>	conj(ACell x)	Adds an element to this data structure, in the natural manner defined by the general data structure type.
ADataStructure<E>	conjAll(ACollection<? extends E> xs)	Adds multiple elements to this data structure, in the natural manner defined by the general data structure type.
abstract boolean	containsKey(ACell key)	Checks if the data structure contains the specified key
final long	count()	Gets the count of elements in this data structure
abstract ADataStructure<E>	empty()	Returns an empty instance of the same Type as this data structure.
abstract ACell	get(ACell key)	Get the value associated with a given key.
abstract ACell	get(ACell key, ACell notFound)	Get the value associated with a given key.
boolean	isDataValue()	Returns true if this cell instance is a first class value, i.e.
final boolean	isEmpty()	Checks if this data structure is empty, i.e.
final int	size()	Gets the size of this data structure as an int.
AString	toCVMString(long limit)	Converts CVM data structure to a CVM String, as per 'print'

Methods inherited from class convex.core.data.ACountable

get, getElementRef, slice, slice

Methods inherited from class convex.core.data.ACell

attachMemorySize, attachRef, cachedEncoding, cachedHash, calcMemorySize, createEncoding, createRef, encode, encodeRaw, equals, equals, genericEquals, getCanonical, getChildRefs, getEncoding, getEncodingLength, getHash, getMemorySize, getMemorySize, getRef, getRef, getRefCount, getTag, getType, hashCode, isCanonical, isCVMValue, isEmbedded, toCanonical, toString, updateRefs, validate, validateCell

Methods inherited from class convex.core.data.AObject

attachEncoding, print, print, print

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface convex.core.data.IWriteable

estimatedEncodingSize

Field Details

count

protected final long count

Constructor Details

ADataStructure

protected ADataStructure(long count)

Method Details

count

public final long count()

Gets the count of elements in this data structure

Specified by:

count in class ACountable<E extends ACell>

Returns:

Number of elements

size

public final int size()

Description copied from class: ACountable

Gets the size of this data structure as an int. Returns Integer.MAX_SIZE if the count is larger than can fit in an int. If this might be a problem, use count() instead.

Overrides:

size in class ACountable<E extends ACell>

Returns:

Number of elements in this collection.

empty

public abstract ADataStructure<E> empty()

Returns an empty instance of the same Type as this data structure.

Specified by:

empty in class ACountable<E extends ACell>

Returns:

An empty data structure

isEmpty

public final boolean isEmpty()

Description copied from class: ACountable

Checks if this data structure is empty, i.e. has a count of zero elements.

Overrides:

isEmpty in class ACountable<E extends ACell>

Returns:

true if this data structure is empty, false otherwise

isDataValue

public boolean isDataValue()

Description copied from class: ACell

Returns true if this cell instance is a first class value, i.e. not a component of a larger data structure Sub-structural cells that are not themselves first class values should return false Everything else should return true.

Specified by:

isDataValue in class ACell

Returns:

true if the object is a Value, false otherwise

conj

public abstract ADataStructure<E> conj(ACell x)

Adds an element to this data structure, in the natural manner defined by the general data structure type. e.g. append at the end of a vector.

Parameters:

x - New element to add

Returns:

The updated data structure, or null if a failure occurred due to invalid element type

conjAll

public ADataStructure<E> conjAll(ACollection<? extends E> xs)

Adds multiple elements to this data structure, in the natural manner defined by the general data structure type. e.g. append at the end of a vector. This may be more efficient than using 'conj' for individual items.

Parameters:

xs - New elements to add

Returns:

The updated data structure, or null if a failure occurred due to invalid element types

assoc

public abstract ADataStructure<E> assoc(ACell key,
 ACell value)

Associates a key with a value in this associative data structure. May return null if the Key or Value is incompatible with the data structure.

Parameters:

key - Associative key

value - Value to associate with key

Returns:

Updates data structure, or null if data types are invalid

get

public abstract ACell get(ACell key)

Get the value associated with a given key.

Parameters:

key - Associative key to look up

Returns:

Value from collection, or a falsey value (null or false) if not found

get

public abstract ACell get(ACell key,
 ACell notFound)

Get the value associated with a given key.

Parameters:

key - Key to look up in data structure

notFound - Value to return if key is not found

Returns:

Value from collection, or notFound value if not found

containsKey

public abstract boolean containsKey(ACell key)

Checks if the data structure contains the specified key

Parameters:

key - Associative key to look up

Returns:

true if the data structure contains the key, false otherwise

toCVMString

public AString toCVMString(long limit)

Converts CVM data structure to a CVM String, as per 'print'

Overrides:

toCVMString in class ACell

Parameters:

limit - Limit of CVM String length in UTF-8 bytes

Returns:

CVM String, or null if limit exceeded

checkIndex

public final void checkIndex(long ix)

Checks if the given index is in range for this data structure

Parameters:

ix - Index to check

Throws:

IndexOutOfBoundsException - if index is invalid