Package convex.core.data

Class StringTree

java.lang.Object

convex.core.data.AObject

convex.core.data.ACell

convex.core.data.ACountable<CVMChar>

convex.core.data.ABlobLike<CVMChar>

convex.core.data.AString

convex.core.data.StringTree

All Implemented Interfaces:

IValidated, IWriteable, Comparable<ABlobLike<?>>

public class StringTree
extends AString

String implementation class wrapping a BlobTree. This String implementation is used to represent long strings.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	MAX_ENCODING_LENGTH
static final int	MINIMUM_LENGTH

Fields inherited from class convex.core.data.AString

length

Fields inherited from class convex.core.data.ACell

cachedRef, memorySize

Fields inherited from class convex.core.data.AObject

encoding

Method Summary

Modifier and Type	Method	Description
byte	byteAt(long i)	Gets a byte at the specified index.
int	compareTo(ABlobLike<?> o)
static StringTree	create(ABlob b)
static StringTree	create(BlobTree b)
int	encodeRaw(byte[] bs, int pos)	Encode the data of this String.
boolean	equals(AString b)	Checks for equality between two strings.
boolean	equalsBytes(ABlob key)	Compare the byte content of this BlobLike to a Blob value
int	estimatedEncodingSize()	Estimate the encoded data size for this Cell.
<R extends ACell> Ref<R>	getRef(int i)	Gets a numbered child Ref from within this Cell.
int	getRefCount()	Gets the number of Refs contained within this Cell.
int	intAt(long i)	Gets 32 bytes integer at given position.
boolean	isCanonical()	Returns true if this Cell is in a canonical representation.
final boolean	isCVMValue()	Returns true if this cell is a first class CVM Value allowable in the CVM state Sub-structural cells that are not themselves first class values should return false Records and types that are not permissible on the CVM should return false.
long	longValue()	Converts this BlobLike to the corresponding long value.
protected void	printEscaped(BlobBuilder sb, long start, long end)	Prints this string as escaped UTF-8
static StringTree	read(long length, Blob b, int pos)	Reads a StringTree from the given Blob encoding.
AString	slice(long start, long end)	Gets a slice of this string, or null if not a valid slice
BlobTree	toBlob()	Converts this String to an equivalent Blob representation.
StringTree	toCanonical()	Converts this Cell to a canonical version.
StringTree	updateRefs(IRefFunction func)	Updates all Refs in this object using the given function.
void	validateCell()	Validates the local structure and invariants of this cell.
int	writeRawData(byte[] bs, int pos)	Write the raw UTF-8 data of this String to a byte array.

Methods inherited from class convex.core.data.AString

append, append, charAt, count, empty, encode, equals, get, getBytes, getElementRef, getTag, getType, hashCode, hexMatch, print, split, toCVMString, toString

Methods inherited from class convex.core.data.ABlobLike

appendHex, byteAtUnchecked, getBytes, getHexDigit, hexEquals, hexLength, hexMatch, isDataValue, toFlatBlob, toHexString, toHexString

Methods inherited from class convex.core.data.ACountable

isEmpty, size, slice

Methods inherited from class convex.core.data.ACell

attachMemorySize, attachRef, cachedEncoding, cachedHash, calcMemorySize, createEncoding, createRef, equals, genericEquals, getCanonical, getChildRefs, getEncoding, getEncodingLength, getHash, getMemorySize, getMemorySize, getRef, isEmbedded, validate

Methods inherited from class convex.core.data.AObject

attachEncoding, print, print

Methods inherited from class java.lang.Object

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

Field Details

MINIMUM_LENGTH

public static final int MINIMUM_LENGTH

See Also:

• Constant Field Values

MAX_ENCODING_LENGTH

public static final int MAX_ENCODING_LENGTH

See Also:

• Constant Field Values

Method Details

create

public static StringTree create(BlobTree b)

create

public static StringTree create(ABlob b)

slice

public AString slice(long start,
 long end)

Description copied from class: AString

Gets a slice of this string, or null if not a valid slice

Specified by:

slice in class AString

Parameters:

start - Start index (inclusive)

end - End index (Exclusive)

Returns:

Specified substring

validateCell

public void validateCell()
                  throws InvalidDataException

Description copied from class: ACell

Validates the local structure and invariants of this cell. Called by validate() super implementation. Should validate directly contained data, but should not validate all other structure of this cell. In particular, should not traverse potentially missing child Refs.

Specified by:

validateCell in class ACell

Throws:

InvalidDataException - If the Cell is invalid

encodeRaw

public int encodeRaw(byte[] bs,
 int pos)

Description copied from class: AString

Encode the data of this String. Assumes tag already written

Specified by:

encodeRaw in class AString

Parameters:

bs - A byte array to which to write the encoding

pos - The offset into the byte array

Returns:

New position after writing

writeRawData

public int writeRawData(byte[] bs,
 int pos)

Description copied from class: AString

Write the raw UTF-8 data of this String to a byte array.

Specified by:

writeRawData in class AString

Parameters:

bs - Destination byte array

pos - Position in target array to write to

Returns:

End position in array after writing

read

public static StringTree read(long length,
 Blob b,
 int pos)
                       throws BadFormatException

Reads a StringTree from the given Blob encoding.

Parameters:

length - Length of StringTree in bytes

b - Blob to read from

pos - Start position in Blob (location of tag byte)

Returns:

New decoded instance

Throws:

BadFormatException - In the event of any encoding error

estimatedEncodingSize

public int estimatedEncodingSize()

Description copied from interface: IWriteable

Estimate the encoded data size for this Cell. Used for quickly sizing buffers. Implementations should try to return a size that is highly likely to contain the entire object when encoded, including the tag byte. Should not traverse soft Refs, i.e. must be usable on arbitrary partial data structures

Returns:

The estimated size for the binary representation of this object.

isCanonical

public boolean isCanonical()

Description copied from class: ACell

Returns true if this Cell is in a canonical representation. Non-canonical objects may be used on a temporary internal basis, they should be converted to canonical representations for general purpose use.

Specified by:

isCanonical in class ACell

Returns:

true if the object is in canonical format, false otherwise

isCVMValue

public final boolean isCVMValue()

Description copied from class: ACell

Returns true if this cell is a first class CVM Value allowable in the CVM state Sub-structural cells that are not themselves first class values should return false Records and types that are not permissible on the CVM should return false. Pretty much everything else should return true. Note: CVM values might not be in a canonical format, e.g. temporary data structures

Specified by:

isCVMValue in class ACell

Returns:

true if the object is a CVM Value, false otherwise

getRefCount

public int getRefCount()

Description copied from class: ACell

Gets the number of Refs contained within this Cell. This number is final / immutable for any given instance and is defined by the Cell encoding rules. Contained Refs may be either external or embedded.

Overrides:

getRefCount in class ACell

Returns:

The number of Refs in this Cell

getRef

public <R extends ACell> Ref<R> getRef(int i)

Description copied from class: ACell

Gets a numbered child Ref from within this Cell. WARNING: May need to convert to a canonical instance

Overrides:

getRef in class ACell

Type Parameters:

R - Type of referenced Cell

Parameters:

i - Index of ref to get

Returns:

The Ref at the specified index

updateRefs

public StringTree updateRefs(IRefFunction func)

Description copied from class: ACell

Updates all Refs in this object using the given function. The function *must not* change the hash value of Refs, in order to ensure structural integrity of modified data structures. The implementation *should* re-attach any original encoding in order to prevent re-encoding or surplus hashing This is a building block for a very sneaky trick that enables use to do a lot of efficient operations on large trees of smart references. Must return the same object if no Refs are altered.

Overrides:

updateRefs in class ACell

Parameters:

func - Ref update function

Returns:

Cell with updated Refs

toCanonical

public StringTree toCanonical()

Description copied from class: ACell

Converts this Cell to a canonical version. Must return this Cell if already canonical, may be O(n) in size of value otherwise. Callers should usually use getCanonical(), which caches canonical instances once created

Specified by:

toCanonical in class AString

Returns:

Canonical version of Cell

byteAt

public byte byteAt(long i)

Description copied from class: AString

Gets a byte at the specified index. Returns -1 (0xff) if outside String.

Specified by:

byteAt in class AString

Parameters:

i - Index into String (byte position)

Returns:

Raw byte value

intAt

public int intAt(long i)

Description copied from class: AString

Gets 32 bytes integer at given position. Extends with 255 (invalid UTF-8) if needed. The main purpose of this function is to enable fast peeking at UTF-8 characters

Overrides:

intAt in class AString

Parameters:

i - Index into String (byte position)

Returns:

Raw integer value

compareTo

public int compareTo(ABlobLike<?> o)

Specified by:

compareTo in interface Comparable<ABlobLike<?>>

Specified by:

compareTo in class ABlobLike<CVMChar>

toBlob

public BlobTree toBlob()

Description copied from class: AString

Converts this String to an equivalent Blob representation. Must round trip all values.

Specified by:

toBlob in class AString

Returns:

Blob representation of UTF-8 String

printEscaped

protected void printEscaped(BlobBuilder sb,
 long start,
 long end)

Description copied from class: AString

Prints this string as escaped UTF-8

Specified by:

printEscaped in class AString

Parameters:

sb -

equals

public boolean equals(AString b)

Description copied from class: AString

Checks for equality between two strings. Should be optimised

Specified by:

equals in class AString

Parameters:

b - Other string (may be null)

Returns:

True if strings are exactly equal, false otherwise

equalsBytes

public boolean equalsBytes(ABlob key)

Description copied from class: ABlobLike

Compare the byte content of this BlobLike to a Blob value

Specified by:

equalsBytes in class ABlobLike<CVMChar>

Parameters:

key - Blob value to compare with

Returns:

`true` if byte contents are exactly equal, `false` otherwise

longValue

public long longValue()

Description copied from class: ABlobLike

Converts this BlobLike to the corresponding long value. Assumes big-endian format, as if the entire blob is interpreted as an unsigned big integer. Higher bytes outside the Long range will be ignored, i.e. the lowest 64 bits are taken

Specified by:

longValue in class ABlobLike<CVMChar>

Returns:

long value of this blob