Package opennlp.tools.util

Class Span

java.lang.Object

opennlp.tools.util.Span

All Implemented Interfaces:

Serializable, Comparable<Span>

Direct Known Subclasses:

LinkedSpan, MascSentence, MascToken, MascWord

public class Span
extends Object
implements Comparable<Span>, Serializable

Class for storing start and end integer offsets.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
Span(int s, int e)	Initializes a new Span.
Span(int s, int e, double prob)	Initializes a new Span.
Span(int s, int e, String type)	Initializes a new Span.
Span(int s, int e, String type, double prob)	Initializes a new Span.
Span(Span span, double prob)	Creates a new immutable Span based on an existing Span, where the existing Span did not include the probability.
Span(Span span, int offset)	Initializes a new Span with an existing Span which is shifted by an offset.

Method Summary

Modifier and Type	Method	Description
int	compareTo(Span s)	Compares the specified Span to the current span.
boolean	contains(int index)	An index with the value of end is considered outside the Span.
boolean	contains(Span s)	Identical spans are considered to contain each other.
boolean	crosses(Span s)	Checks if the specified Span crosses this span.
boolean	equals(Object o)
CharSequence	getCoveredText(CharSequence text)
int	getEnd()	Note: that the returned index is one past the actual end of the span in the text, or the first element past the end of the span.
double	getProb()
int	getStart()
String	getType()
int	hashCode()
boolean	intersects(Span s)	Checks if the specified Span intersects with this span.
int	length()
static String[]	spansToStrings(Span[] spans, CharSequence s)	Converts an array of spans to an array of String.
static String[]	spansToStrings(Span[] spans, String[] tokens)
boolean	startsWith(Span s)
String	toString()
Span	trim(CharSequence text)

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Span

public Span(int s,
            int e,
            String type)

Initializes a new Span. Sets the prob to 0 as default.

Parameters:

s - The start position of a Span. Must be equal to or greater than 0. Must not be greater than e.

e - The end position of a Span, which is +1 more than the last element in the span. Must be equal to or greater than 0.

type - the type of the span

Throws:

IllegalArgumentException - Thrown if given parameters are invalid.

Span

public Span(int s,
            int e,
            String type,
            double prob)

Initializes a new Span.

Parameters:

s - The start position of a Span. Must be equal to or greater than 0. Must not be greater than e.

e - The end position of a Span, which is +1 more than the last element in the span. Must be equal to or greater than 0.

type - The type of the Span

prob - The probability of the Span.

Throws:

IllegalArgumentException - Thrown if given parameters are invalid.

Span

public Span(int s,
            int e)

Initializes a new Span. Sets the prob to 0 as default.

Parameters:

s - The start position of a Span. Must be equal to or greater than 0. Must not be greater than e.

e - The end position of a Span, which is +1 more than the last element in the span. Must be equal to or greater than 0.

Throws:

IllegalArgumentException - Thrown if given parameters are invalid.

Span

public Span(int s,
            int e,
            double prob)

Initializes a new Span. Sets the prob to 0 as default.

Parameters:

s - The start position of a Span. Must be equal to or greater than 0. Must not be greater than e.

e - The end position of a Span, which is +1 more than the last element in the span. Must be equal to or greater than 0.

prob - The probability of the Span

Throws:

IllegalArgumentException - Thrown if given parameters are invalid.

Span

public Span(Span span,
            int offset)

Initializes a new Span with an existing Span which is shifted by an offset.

Parameters:

span - The existing Span.

offset - The positive or negative shift offset.

Throws:

IllegalArgumentException - Thrown if given parameters are invalid.

Span

public Span(Span span,
            double prob)

Creates a new immutable Span based on an existing Span, where the existing Span did not include the probability.

Parameters:

span - The Span that has no prob or the prob is incorrect and a new Span must be generated.

prob - The probability of the Span.

Throws:

IllegalArgumentException - Thrown if given parameters are invalid.

Method Detail

getStart

public int getStart()

Returns:

Retrieves the start of a Span. Guaranteed to be greater than 0.

getEnd

public int getEnd()

Note: that the returned index is one past the actual end of the span in the text, or the first element past the end of the span.

Returns:

Retrieves the end of a Span. Guaranteed to be greater than 0.

getType

public String getType()

Returns:

Retrieves the type of a Span or null if not set.

length

public int length()

Returns:

Returns the length of a Span. Guaranteed to be greater than 0.

contains

public boolean contains(Span s)

Identical spans are considered to contain each other.

Parameters:

s - The Span to compare with this Span.

Returns:

true is the specified {Span s} is contained by this span, false otherwise.

contains

public boolean contains(int index)

An index with the value of end is considered outside the Span.

Parameters:

index - the index to test with this Span.

Returns:

true if the span contains this specified index, false otherwise.

startsWith

public boolean startsWith(Span s)

Parameters:

s - The Span to compare with this span.

Returns:

true if the specified span starts with this span and is contained in this span, false otherwise

intersects

public boolean intersects(Span s)

Checks if the specified Span intersects with this span.

Parameters:

s - The Span to compare with this span.

Returns:

true is the spans overlap, false otherwise.

crosses

public boolean crosses(Span s)

Checks if the specified Span crosses this span.

Parameters:

s - The Span to compare with this span.

Returns:

true is the given Span overlaps this span and contains a non-overlapping section, false otherwise.

getCoveredText

public CharSequence getCoveredText(CharSequence text)

Parameters:

text - The text to analyze.

Returns:

Retrieves the (sub)string covered by the current Span of the specified text.

Throws:

IllegalArgumentException - Thrown if parameters violated a constraint.

trim

public Span trim(CharSequence text)

Parameters:

text - The text to analyze.

Returns:

A copy of this Span with leading and trailing white spaces removed, or the same object if already trimmed.

compareTo

public int compareTo(Span s)

Compares the specified Span to the current span.

Specified by:

compareTo in interface Comparable<Span>

Parameters:

s - The Span instance to compare against.

See Also:

Comparable.compareTo(Object)

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object

Returns:

A human-readable representation of this Span.

spansToStrings

public static String[] spansToStrings(Span[] spans,
                                      CharSequence s)

Converts an array of spans to an array of String.

Parameters:

spans - The array used as input.

s - The CharSequence used to compute covered text.

Returns:

The converted array of strings.

spansToStrings

public static String[] spansToStrings(Span[] spans,
                                      String[] tokens)

getProb

public double getProb()

Returns:

Retrieves the probability represented by a Span.