com.ibm.able.data
Class AbleStringLiteral

java.lang.Object
  com.ibm.able.data.AbleLiteral
      com.ibm.able.data.AbleStringLiteral

All Implemented Interfaces:

AbleRd, java.io.Serializable

public class AbleStringLiteral

extends AbleLiteral

implements java.io.Serializable

This class wraps a value of the Java type java.lang.String in an object. An object of type AbleStringLiteral contains a single, immutable field whose type is String. Instances of AbleStringLiteral are used by the Able rules classes in clauses and expressions. In addition, this class provides methods for converting a String to a numeric value as well as other logical comparison methods useful when dealing with a String.

See Also:

Serialized Form

Field Summary

static AbleStringLiteral	EMPTY_STRING_LITERAL
protected static java.util.WeakHashMap	internedStrings internedStrings: A weak hash map of strings.
static boolean	InternStringLiterals InternStringLiterals: Flag to indicate if string literals are interned.
protected java.lang.String	myValue The immutable value of this literal.

Constructor Summary

AbleStringLiteral()
Create a new literal with an empty string value.

AbleStringLiteral(java.lang.String theValue)
Create a new literal with the specified value.

Method Summary

java.lang.String	arlCRdString() Return a formal ARL "clause read" string that describes this data object.
boolean	cmpEq(AbleRd theRhs) Comparison, equal to: compare the current value of this data object to the current value of theRhs.
boolean	cmpGt(AbleRd theRhs) Comparison, greater than: compare the current value of this data object to the current value of theRhs.
boolean	cmpGtEq(AbleRd theRhs) Comparison, greater than or equal to: compare the current value of this data object to the current value of theRhs.
boolean	cmpLt(AbleRd theRhs) Comparison, less than: compare the current value of this data object to the current value of theRhs.
boolean	cmpLtEq(AbleRd theRhs) Comparison, less than or equal to: compare the current value of this data object to the current value of theRhs.
boolean	cmpNeq(AbleRd theRhs) Comparison, not equal to: compare the current value of this data object to the current value of theRhs.
AbleLiteral	compPlus(AbleRd theRhs) Compute, concatenate the current value of this data object to the current value of theRhs.
boolean	equals(java.lang.Object theOtherObject)
static java.lang.String	findOrCreateInternedString(java.lang.String token) See if the specified string exists, and if it does, return it.
boolean	getBooleanValue() Retrieve the value of this data object as a boolean value.
int	getDataType() Retrieve the data type of this data object.
java.lang.Class	getDataTypeClass() Retrieve the actual class of this object's underlying data type.
java.lang.String	getDataTypeClassName() Retrieve the name of the class of this object's underlying data type.
AbleFuzzySet	getFuzzyValue() Retrieve the value of this data object as a fuzzy value.
java.lang.Object	getGenericValue() Retrieve the value of this data object as an Object.
double	getNumericValue() Retrieve the value of this data object as a numeric value.
java.lang.String	getStringValue() Retrieve the value of this data object as a string value.
AbleLiteral	getValue() Retrieve the value of this data object as a literal.
int	hashCode()
java.lang.String	toString() Retrieve a string describing (the contents of) the object.
java.lang.String	traceString(int theTraceStringFlavor) Retrieve a string describing (the contents of) the object.
static java.lang.String	valueOf(java.lang.String theValue) Take a string with escape characters and resolve (that is, remove) them.
java.lang.String	xmlCRdString() Return a formal XML "clause read" string that describes this data object.

Methods inherited from class com.ibm.able.data.AbleLiteral

bitwiseAND, bitwiseNOT, bitwiseOR, bitwiseShiftLeft, bitwiseShiftRight, bitwiseShiftRightZeroFill, bitwiseXOR, cmpIs, compDivide, compMinus, compModulo, compMultiply, compUnaryMinus, getDataTypeAsString, getReferent, getReferents, getTemplateString, isConstant, logicalAND, logicalNOT, logicalOR

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_STRING_LITERAL

public static final AbleStringLiteral EMPTY_STRING_LITERAL

InternStringLiterals

public static boolean InternStringLiterals

InternStringLiterals: Flag to indicate if string literals are interned.

internedStrings

protected static volatile java.util.WeakHashMap internedStrings

internedStrings: A weak hash map of strings.

myValue

protected java.lang.String myValue

The immutable value of this literal.

Constructor Detail

AbleStringLiteral

public AbleStringLiteral()

Create a new literal with an empty string value.

AbleStringLiteral

public AbleStringLiteral(java.lang.String theValue)

Create a new literal with the specified value.

Parameters:

theValue - The value to which this literal is to be set.

Method Detail

valueOf

public static java.lang.String valueOf(java.lang.String theValue)

Take a string with escape characters and resolve (that is, remove) them. Used by the ARL parsers. For example "c:\\joe\\test.arl" would be converted to "c:\joe\test.arl".

Parameters:

theValue - The input string that contains valid escape '\' character sequences

Returns:

A string containing no escape char sequences

getBooleanValue

public boolean getBooleanValue()
                        throws AbleDataException

Retrieve the value of this data object as a boolean value.

Specified by:

getBooleanValue in interface AbleRd

Specified by:

getBooleanValue in class AbleLiteral

Returns:

A boolean, if the value of this object can be represented as a boolean value. Leading blanks, trailing blanks, and case are all ignored when determining if the value can be represented as a boolean.

Throws:

AbleDataException - If the value of this object cannot be represented as a boolean value.

getFuzzyValue

public AbleFuzzySet getFuzzyValue()
                           throws AbleDataException

Retrieve the value of this data object as a fuzzy value.

Specified by:

getFuzzyValue in interface AbleRd

Specified by:

getFuzzyValue in class AbleLiteral

Returns:

A fuzzy set, if the value of this object can be represented as a fuzzy value. This method always throws an exception.

Throws:

AbleDataException - If the value of this object cannot be represented as a fuzzy value.

getGenericValue

public java.lang.Object getGenericValue()
                                 throws AbleDataException

Retrieve the value of this data object as an Object.

Specified by:

getGenericValue in interface AbleRd

Specified by:

getGenericValue in class AbleLiteral

Returns:

A String object.

Throws:

AbleDataException - If the value of this object cannot be represented as an Object.

getNumericValue

public double getNumericValue()
                       throws AbleDataException

Retrieve the value of this data object as a numeric value.

Specified by:

getNumericValue in interface AbleRd

Specified by:

getNumericValue in class AbleLiteral

Returns:

A double, if the value of this object can be represented as a numeric value.

Throws:

AbleDataException - If the value of this object cannot be represented as a numeric value.

getStringValue

public java.lang.String getStringValue()
                                throws AbleDataException

Retrieve the value of this data object as a string value.

Specified by:

getStringValue in interface AbleRd

Specified by:

getStringValue in class AbleLiteral

Returns:

A String, if the value of this object can be represented as a string value.

Throws:

AbleDataException - If the value of this object cannot be represented as a string value.

getValue

public AbleLiteral getValue()
                     throws AbleDataException

Retrieve the value of this data object as a literal.

Specified by:

getValue in interface AbleRd

Specified by:

getValue in class AbleLiteral

Returns:

An AbleStringLiteral object.

Throws:

AbleDataException - If the value of this object cannot be represented as a literal.

getDataTypeClass

public java.lang.Class getDataTypeClass()

Description copied from class: AbleLiteral

Retrieve the actual class of this object's underlying data type.

Specified by:

getDataTypeClass in interface AbleRd

Specified by:

getDataTypeClass in class AbleLiteral

Returns:

The class of the underlying data type.

getDataTypeClassName

public java.lang.String getDataTypeClassName()

Description copied from class: AbleLiteral

Retrieve the name of the class of this object's underlying data type.

Specified by:

getDataTypeClassName in interface AbleRd

Specified by:

getDataTypeClassName in class AbleLiteral

Returns:

A String that is the name of the class of the underlying data type.

arlCRdString

public java.lang.String arlCRdString()

Return a formal ARL "clause read" string that describes this data object.

Specified by:

arlCRdString in interface AbleRd

Specified by:

arlCRdString in class AbleLiteral

Returns:

A String describing the data object in formal rule language.

xmlCRdString

public java.lang.String xmlCRdString()

Return a formal XML "clause read" string that describes this data object.

Specified by:

xmlCRdString in interface AbleRd

Specified by:

xmlCRdString in class AbleLiteral

Returns:

A String describing the data object in XML. A form similar to "<token value=\"some string\"/>" is returned.

cmpEq

public boolean cmpEq(AbleRd theRhs)
              throws AbleDataException

Comparison, equal to: compare the current value of this data object to the current value of theRhs.

"==" is used for numeric and boolean compares; equals() is used for Object compares; and Collator.equals() is used for String compares.

Specified by:

cmpEq in interface AbleRd

Overrides:

cmpEq in class AbleLiteral

Parameters:

theRhs - The right-hand side of the comparison.

Returns:

true, if this data object is equal to theRhs; false, otherwise.

Throws:

AbleDataException - If the right-hand side cannot be converted (if necessary) and compared to this data object.

cmpGt

public boolean cmpGt(AbleRd theRhs)
              throws AbleDataException

Comparison, greater than: compare the current value of this data object to the current value of theRhs.

">" is used for numeric compares; Collator.compare() is used for String compares. Use of other data types on the left-hand side causes an exception.

Specified by:

cmpGt in interface AbleRd

Overrides:

cmpGt in class AbleLiteral

Parameters:

theRhs - The right-hand side of the comparison.

Returns:

true, if this data object is greater than theRhs; false, otherwise.

Throws:

AbleDataException - If the right-hand side cannot be converted (if necessary) and compared to this data object.

cmpGtEq

public boolean cmpGtEq(AbleRd theRhs)
                throws AbleDataException

Comparison, greater than or equal to: compare the current value of this data object to the current value of theRhs.

">=" is used for numeric compares; Collator.compare() is used for String compares. Use of other data types on the left-hand side causes an exception.

Specified by:

cmpGtEq in interface AbleRd

Overrides:

cmpGtEq in class AbleLiteral

Parameters:

theRhs - The right-hand side of the comparison.

Returns:

true, if this data object is greater than or equal to theRhs; false, otherwise.

Throws:

AbleDataException - If the right-hand side cannot be converted (if necessary) and compared to this data object.

cmpLt

public boolean cmpLt(AbleRd theRhs)
              throws AbleDataException

Comparison, less than: compare the current value of this data object to the current value of theRhs.

"<" is used for numeric compares; Collator.compare() is used for String compares. Use of other data types on the left-hand side causes an exception.

Specified by:

cmpLt in interface AbleRd

Overrides:

cmpLt in class AbleLiteral

Parameters:

theRhs - The right-hand side of the comparison.

Returns:

true, if this data object is less than theRhs; false, otherwise.

Throws:

AbleDataException - If the right-hand side cannot be converted (if necessary) and compared to this data object.

cmpLtEq

public boolean cmpLtEq(AbleRd theRhs)
                throws AbleDataException

Comparison, less than or equal to: compare the current value of this data object to the current value of theRhs.

"<=" is used for numeric compares; Collator.compare() is used for String compares. Use of other data types on the left-hand side causes an exception.

Specified by:

cmpLtEq in interface AbleRd

Overrides:

cmpLtEq in class AbleLiteral

Parameters:

theRhs - The right-hand side of the comparison.

Returns:

true, if this data object is less than or equal to theRhs; false, otherwise.

Throws:

AbleDataException - If the right-hand side cannot be converted (if necessary) and compared to this data object.

cmpNeq

public boolean cmpNeq(AbleRd theRhs)
               throws AbleDataException

Comparison, not equal to: compare the current value of this data object to the current value of theRhs.

"!=" is used for numeric and boolean compares; ! equals() is used for Object compares; and ! Collator.equals() is used for String compares.

Specified by:

cmpNeq in interface AbleRd

Overrides:

cmpNeq in class AbleLiteral

Parameters:

theRhs - The right-hand side of the comparison.

Returns:

true, if this data object is not equal to theRhs; false, otherwise.

Throws:

AbleDataException - If the right-hand side cannot be converted (if necessary) and compared to this data object.

compPlus

public AbleLiteral compPlus(AbleRd theRhs)
                     throws AbleDataException

Compute, concatenate the current value of this data object to the current value of theRhs.

"+" is used for String concatenation.

Specified by:

compPlus in interface AbleRd

Overrides:

compPlus in class AbleLiteral

Parameters:

theRhs - The right-hand side of the comparison.

Returns:

The result of the concatenation operation.

Throws:

AbleDataException - If the right-hand side cannot be converted (if necessary) and compared to this data object.

equals

public boolean equals(java.lang.Object theOtherObject)

hashCode

public int hashCode()

toString

public java.lang.String toString()

Retrieve a string describing (the contents of) the object.

Overrides:

toString in class AbleLiteral

Returns:

A String containing the current contents of the object.

traceString

public java.lang.String traceString(int theTraceStringFlavor)

Retrieve a string describing (the contents of) the object.

Specified by:

traceString in interface AbleRd

Specified by:

traceString in class AbleLiteral

Parameters:

theTraceStringFlavor - An Able.TraceStringFlavor value.

Returns:

A String containing the current contents of the object.

getDataType

public int getDataType()

Description copied from class: AbleLiteral

Retrieve the data type of this data object.

Specified by:

getDataType in interface AbleRd

Specified by:

getDataType in class AbleLiteral

Returns:

An AbleData.<DataType> constant.

See Also:

AbleRd.getDataType()

findOrCreateInternedString

public static java.lang.String findOrCreateInternedString(java.lang.String token)

See if the specified string exists, and if it does, return it. If the string doesn't already exist, create it, add it to the cache, and then return it.

Parameters:

token - A parsed token (a string) that is used as a literal.

Returns:

A String object the is guarenteed to be == if it is equal().