net.sf.saxon.value

Class IntegerValue

public final class IntegerValue extends NumericValue

An integer value: note this is a subtype of decimal in XML Schema, not a primitive type. This class also supports the built-in subtypes of xs:integer. Actually supports a value in the range permitted by a Java "long"

Field Summary
static IntegerValue	MAX_LONG IntegerValue representing the maximum value for this class
static IntegerValue	MINUS_ONE IntegerValue representing the value -1
static IntegerValue	MIN_LONG IntegerValue representing the minimum value for this class
static IntegerValue	PLUS_ONE IntegerValue representing the value +1
static IntegerValue	ZERO IntegerValue representing the value zero

Constructor Summary
	IntegerValue(long value) Constructor supplying a long
	IntegerValue(long val, AtomicType type) Constructor for a subtype, supplying an integer

Method Summary
NumericValue	arithmetic(int operator, NumericValue other, XPathContext context) Evaluate a binary arithmetic operator.
NumericValue	ceiling() Implement the XPath ceiling() function
static boolean	checkBigRange(BigInteger big, AtomicType type) Check that a BigInteger is within the required range for a given integer subtype.
boolean	checkRange(AtomicType type) This class allows subtypes of xs:integer to be held, as well as xs:integer values.
static boolean	checkRange(long value, AtomicType type) Check that a value is in range for the specified subtype of xs:integer
int	compareTo(Object other) Compare the value to another numeric value
AtomicValue	convertPrimitive(BuiltInAtomicType requiredType, boolean validate, XPathContext context) Convert to target data type
Object	convertToJava(Class target, XPathContext context) Convert to Java object (for passing to external functions)
ValidationException	convertToSubtype(AtomicType subtype, boolean validate) Convert the value to a subtype of xs:integer
boolean	effectiveBooleanValue(XPathContext context) Return the effective boolean value of this integer
NumericValue	floor() Implement the XPath floor() function
ItemType	getItemType(TypeHierarchy th) Determine the data type of the expression
String	getStringValue() Get the value as a String
int	hashCode() Get the hashCode.
boolean	isWholeNumber() Determine whether the value is a whole number, that is, whether it compares equal to some integer
long	longValue() Get the value
NumericValue	negate() Negate the value
NumericValue	round() Implement the XPath round() function
NumericValue	roundToHalfEven(int scale) Implement the XPath round-to-half-even() function
boolean	schemaEquals(Value obj) Compare two values for equality.
void	setSubType(AtomicType type) This class allows subtypes of xs:integer to be held, as well as xs:integer values.
double	signum() Determine whether the value is negative, zero, or positive
static AtomicValue	stringToInteger(CharSequence s) Static factory method to convert strings to integers.

Field Detail

MAX_LONG

public static final IntegerValue MAX_LONG

IntegerValue representing the maximum value for this class

MINUS_ONE

public static final IntegerValue MINUS_ONE

IntegerValue representing the value -1

MIN_LONG

public static final IntegerValue MIN_LONG

IntegerValue representing the minimum value for this class

PLUS_ONE

public static final IntegerValue PLUS_ONE

IntegerValue representing the value +1

ZERO

public static final IntegerValue ZERO

IntegerValue representing the value zero

Constructor Detail

IntegerValue

public IntegerValue(long value)

Constructor supplying a long

Parameters: value the value of the IntegerValue

IntegerValue

public IntegerValue(long val, AtomicType type)

Constructor for a subtype, supplying an integer

Parameters: val The supplied value, as an integer type the required item type, a subtype of xs:integer

Throws: DynamicError if the supplied value is out of range for the target type

Method Detail

arithmetic

public NumericValue arithmetic(int operator, NumericValue other, XPathContext context)

Evaluate a binary arithmetic operator.

Parameters: operator the operator to be applied, identified by a constant in the Tokenizer class other the other operand of the arithmetic expression

Returns: the result of performing the arithmetic operation

Throws: XPathException if an arithmetic failure occurs, e.g. divide by zero

ceiling

public NumericValue ceiling()

Implement the XPath ceiling() function

Returns: the integer value, unchanged

checkBigRange

static boolean checkBigRange(BigInteger big, AtomicType type)

Check that a BigInteger is within the required range for a given integer subtype. This method is expensive, so it should not be used unless the BigInteger is outside the range of a long.

checkRange

public boolean checkRange(AtomicType type)

This class allows subtypes of xs:integer to be held, as well as xs:integer values. This method checks that the value is within range, and also sets the type label.

Parameters: type the subtype of integer required

Returns: true if successful, false if value is out of range for the subtype

checkRange

static boolean checkRange(long value, AtomicType type)

Check that a value is in range for the specified subtype of xs:integer

Parameters: value the value to be checked type the required item type, a subtype of xs:integer

Returns: true if successful, false if value is out of range for the subtype

compareTo

public int compareTo(Object other)

Compare the value to another numeric value

Parameters: other the numeric value to be compared to this value

Returns: -1 if this value is less than the other, 0 if they are equal, +1 if this value is greater

convertPrimitive

public AtomicValue convertPrimitive(BuiltInAtomicType requiredType, boolean validate, XPathContext context)

Convert to target data type

Parameters: requiredType an integer identifying the required atomic type context

Returns: an AtomicValue, a value of the required type

convertToJava

public Object convertToJava(Class target, XPathContext context)

Convert to Java object (for passing to external functions)

Parameters: target The Java class to which conversion is required

Returns: the Java object that results from the conversion; always an instance of the target class

Throws: XPathException if conversion is not possible, or fails

convertToSubtype

public ValidationException convertToSubtype(AtomicType subtype, boolean validate)

Convert the value to a subtype of xs:integer

Parameters: subtype the target subtype validate true if validation is required; false if the caller already knows that the value is valid

Returns: null if the conversion succeeds; a ValidationException describing the failure if it fails. Note that the exception is returned, not thrown.

effectiveBooleanValue

public boolean effectiveBooleanValue(XPathContext context)

Return the effective boolean value of this integer

Parameters: context The dynamic evaluation context; ignored in this implementation of the method

Returns: false if the integer is zero, otherwise true

floor

public NumericValue floor()

Implement the XPath floor() function

Returns: the integer value, unchanged

getItemType

public ItemType getItemType(TypeHierarchy th)

Determine the data type of the expression

Parameters: th

Returns: the actual data type

getStringValue

public String getStringValue()

Get the value as a String

Returns: a String representation of the value

hashCode

public int hashCode()

Get the hashCode. This must conform to the rules for other NumericValue hashcodes

isWholeNumber

public boolean isWholeNumber()

Determine whether the value is a whole number, that is, whether it compares equal to some integer

Returns: always true for this implementation

longValue

public long longValue()

Get the value

Returns: the value of the xs:integer, as a Java long

negate

public NumericValue negate()

Negate the value

Returns: the result of inverting the sign of the value

round

public NumericValue round()

Implement the XPath round() function

Returns: the integer value, unchanged

roundToHalfEven

public NumericValue roundToHalfEven(int scale)

Implement the XPath round-to-half-even() function

Parameters: scale number of digits required after the decimal point; the value -2 (for example) means round to a multiple of 100

Returns: if the scale is >=0, return this value unchanged. Otherwise round it to a multiple of 10**-scale

schemaEquals

public boolean schemaEquals(Value obj)

Compare two values for equality. This supports identity constraints in XML Schema, which allow list-valued elements and attributes to participate in key and uniqueness constraints. This method returns false if any error occurs during the comparison, or if any of the items in either sequence is a node rather than an atomic value. The default implementation of schemaEquals() is the same as equals(), but subclasses can override this.

setSubType

public void setSubType(AtomicType type)

This class allows subtypes of xs:integer to be held, as well as xs:integer values. This method sets the required type label. It is the caller's responsibility to check that the value is within range.

signum

public double signum()

Determine whether the value is negative, zero, or positive

Returns: -1 if negative, 0 if zero, +1 if positive, NaN if NaN

stringToInteger

public static AtomicValue stringToInteger(CharSequence s)

Static factory method to convert strings to integers.

Parameters: s CharSequence representing the string to be converted

Returns: either an IntegerValue or a BigIntegerValue representing the value of the String, or an ErrorValue encapsulating an Exception if the value cannot be converted.