com.hp.hpl.jena.sparql.util

Class Context

java.lang.Object

com.hp.hpl.jena.sparql.util.Context

public class Context
extends Object

A class for setting and keeping named values. Used to pass implementation-specific parameters across general interfaces.

Field Summary

Fields

Modifier and Type	Field and Description
static Context	emptyContext

Constructor Summary

Constructors

Constructor and Description
Context() Create an empty context
Context(Context cxt) Create a context and initialize it with a copy of the named values of another one.

Method Summary

Methods

Modifier and Type	Method and Description
void	addCallback(Callback<Symbol> m)
Context	copy() Return a copy of this context.
Object	get(Symbol property) Get the object value of a property or null
Object	get(Symbol property, Object defaultValue) Get the object value of a property - return the default value if not present .
String	getAsString(Symbol property) Get the value a string (uses .toString() if the value is not null)
String	getAsString(Symbol property, String defaultValue) Get the value a string (uses .toString() if the value is not null) - supply a default string value
List<Callback<Symbol>>	getCallbacks()
boolean	hasValue(Symbol property, Object value) Test whether a named value is a specific value (.equals)
boolean	hasValueAsString(Symbol property, String value) Test whether a named value (as a string) has a specific string form
boolean	hasValueAsString(Symbol property, String value, boolean ignoreCase) Test whether a named value (as a string) has a specific string form - can ignore case
boolean	isDefined(Symbol property) Is a property set?
boolean	isFalse(Symbol property) Is the value 'false' (either set to the string "false" or Boolean.FALSE)
boolean	isFalseOrUndef(Symbol property) Is the value 'false' (either set to the string "false" or Boolean.FALSE) or undefined
boolean	isTrue(Symbol property) Is the value 'true' (either set to the string "true" or Boolean.TRUE)
boolean	isTrueOrUndef(Symbol property) Is the value 'true' (either set to the string "true" or Boolean.TRUE) or undefined?
boolean	isUndef(Symbol property) Is a property not set?
Set<Symbol>	keys() Set of properties (as Symbols) currently defined
void	put(Symbol property, Object value) Store a named value - overwrites any previous set value
void	putAll(Context other)
void	remove(Symbol property) Remove any value associated with a property
void	removeCallback(Callback<Symbol> m)
void	set(Symbol property, boolean value) Store a named value - overwrites any previous set value
void	set(Symbol property, Object value) Store a named value - overwrites any previous set value
void	setFalse(Symbol property) Set propety value to be false
void	setIfUndef(Symbol property, Object value) Store a named value only if it is not currently set
void	setTrue(Symbol property) Set propety value to be true
static Context	setupContext(Context context, DatasetGraph dataset)
int	size() Return the number of context items
String	toString()
void	unset(Symbol property) Remove any value associated with a property - alternative method name

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

emptyContext

public static final Context emptyContext

Constructor Detail

Context

public Context()

Create an empty context

Context

public Context(Context cxt)

Create a context and initialize it with a copy of the named values of another one. Shallow copy: the values themselves are not copied

Method Detail

copy

public Context copy()

Return a copy of this context. Modifications of the copy do not affect the original context.

get

public Object get(Symbol property)

Get the object value of a property or null

get

public Object get(Symbol property,
         Object defaultValue)

Get the object value of a property - return the default value if not present .

put

public void put(Symbol property,
       Object value)

Store a named value - overwrites any previous set value

set

public void set(Symbol property,
       Object value)

Store a named value - overwrites any previous set value

set

public void set(Symbol property,
       boolean value)

Store a named value - overwrites any previous set value

setIfUndef

public void setIfUndef(Symbol property,
              Object value)

Store a named value only if it is not currently set

remove

public void remove(Symbol property)

Remove any value associated with a property

unset

public void unset(Symbol property)

Remove any value associated with a property - alternative method name

isDefined

public boolean isDefined(Symbol property)

Is a property set?

isUndef

public boolean isUndef(Symbol property)

Is a property not set?

getAsString

public String getAsString(Symbol property,
                 String defaultValue)

Get the value a string (uses .toString() if the value is not null) - supply a default string value

getAsString

public String getAsString(Symbol property)

Get the value a string (uses .toString() if the value is not null)

putAll

public void putAll(Context other)

setTrue

public void setTrue(Symbol property)

Set propety value to be true

setFalse

public void setFalse(Symbol property)

Set propety value to be false

isTrue

public boolean isTrue(Symbol property)

Is the value 'true' (either set to the string "true" or Boolean.TRUE)

isTrueOrUndef

public boolean isTrueOrUndef(Symbol property)

Is the value 'true' (either set to the string "true" or Boolean.TRUE) or undefined?

isFalse

public boolean isFalse(Symbol property)

Is the value 'false' (either set to the string "false" or Boolean.FALSE)

isFalseOrUndef

public boolean isFalseOrUndef(Symbol property)

Is the value 'false' (either set to the string "false" or Boolean.FALSE) or undefined

hasValue

public boolean hasValue(Symbol property,
               Object value)

Test whether a named value is a specific value (.equals)

hasValueAsString

public boolean hasValueAsString(Symbol property,
                       String value)

Test whether a named value (as a string) has a specific string form

hasValueAsString

public boolean hasValueAsString(Symbol property,
                       String value,
                       boolean ignoreCase)

Test whether a named value (as a string) has a specific string form - can ignore case

keys

public Set<Symbol> keys()

Set of properties (as Symbols) currently defined

size

public int size()

Return the number of context items

addCallback

public void addCallback(Callback<Symbol> m)

removeCallback

public void removeCallback(Callback<Symbol> m)

getCallbacks

public List<Callback<Symbol>> getCallbacks()

toString

public String toString()

Overrides:

toString in class Object

setupContext

public static Context setupContext(Context context,
                   DatasetGraph dataset)