com.pervasive.datarush.tokens.scalar

Class StringToken

java.lang.Object

com.pervasive.datarush.tokens.scalar.StringToken

All Implemented Interfaces:

DataToken, ScalarToken, ScalarValued, StringValued, TokenValued, ScalarTyped, TokenTyped, Serializable, Comparable<StringToken>

public final class StringToken
extends Object
implements ScalarToken, Comparable<StringToken>

An immutable StringValued object.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static StringToken	NULL A null valued StringToken
static StringToken	ZERO A zero valued StringToken
static String	ZERO_VALUE The string representing a zero value, the empty string.

Constructor Summary

Constructors

Constructor and Description
StringToken(String value) Constructs an new token with the given non-null string.
StringToken(StringValued value) Constructs a new token with the string value in the given container.

Method Summary

Modifier and Type	Method and Description
String	asString() Gets the contained string value.
int	compareTo(StringToken that)
boolean	equals(Object obj) Indicates whether another object is equal to this token.
ScalarTokenType	getType() Gets the data type of the token.
int	hashCode() Returns a hash code for the token.
boolean	isNull() Indicates whether the token is null valued.
boolean	isZero() Indicates whether the value is the zero value for the type.
static StringToken	parse(String value) Converts a string into a token.
String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.pervasive.datarush.tokens.DataToken

toString

Methods inherited from interface com.pervasive.datarush.tokens.scalar.ScalarValued

getType, isZero

Methods inherited from interface com.pervasive.datarush.tokens.TokenValued

isNull

Field Detail

NULL

public static final StringToken NULL

A null valued StringToken

ZERO_VALUE

public static final String ZERO_VALUE

The string representing a zero value, the empty string.

See Also:

Constant Field Values

ZERO

public static final StringToken ZERO

A zero valued StringToken

Constructor Detail

StringToken

public StringToken(StringValued value)

Constructs a new token with the string value in the given container.

Parameters:

value - a StringValued containing the desired value

StringToken

public StringToken(String value)

Constructs an new token with the given non-null string. If a null valued token is desired, use NULL.

Parameters:

value - the string value of the token

Throws:

NullPointerException - if the value is null.

Method Detail

compareTo

public int compareTo(StringToken that)

Specified by:

compareTo in interface Comparable<StringToken>

equals

public boolean equals(Object obj)

Description copied from interface: DataToken

Indicates whether another object is equal to this token. Two null valued tokens are considered equal. This differs from the behavior of TokenComparator.equal(TokenValued,TokenValued) but makes it possible to store DataTokens in Maps.

Specified by:

equals in interface DataToken

Overrides:

equals in class Object

Parameters:

obj - the object to compare

Returns:

true if the other object is a token of the same type and contains the same value, false otherwise.

hashCode

public int hashCode()

Description copied from interface: DataToken

Returns a hash code for the token. This value is guaranteed to be consistent with that returned by TokenConverter.asHashCode(TokenValued).

Specified by:

hashCode in interface DataToken

Overrides:

hashCode in class Object

Returns:

a hash code value for the token

parse

public static StringToken parse(String value)

Converts a string into a token.

Parameters:

value - the string value of the token

Returns:

a token with the specified value

toString

public String toString()

Overrides:

toString in class Object

getType

public ScalarTokenType getType()

Description copied from interface: TokenValued

Gets the data type of the token. This type will dictate the valid values that can be contained.

Specified by:

getType in interface ScalarValued

Specified by:

getType in interface TokenValued

Specified by:

getType in interface ScalarTyped

Specified by:

getType in interface TokenTyped

Returns:

the token type.

asString

public final String asString()

Description copied from interface: StringValued

Gets the contained string value.

Specified by:

asString in interface StringValued

Returns:

the contained value as a String. If null valued, as indicated by TokenValued.isNull(), the empty string ("") is returned.

isZero

public boolean isZero()

Description copied from interface: ScalarValued

Indicates whether the value is the zero value for the type. Zero values are not stored in sparse representation formats.

Specified by:

isZero in interface ScalarValued

Returns:

true if the value is the zero value, false otherwise.

isNull

public final boolean isNull()

Description copied from interface: TokenValued

Indicates whether the token is null valued. Tokens support null values analogous to SQL. Before accessing the value of the container, it is usually best to ensure it is not null valued using this method.

Specified by:

isNull in interface TokenValued

Returns:

true if the token is null valued, false otherwise