package net.sf.saxon.value;
import net.sf.saxon.Err;
import net.sf.saxon.expr.XPathContext;
import net.sf.saxon.om.FastStringBuffer;
import net.sf.saxon.om.StandardNames;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.type.*;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.regex.Pattern;
/**
* A decimal value
*/
public final class DecimalValue extends NumericValue {
public static final int DIVIDE_PRECISION = 18;
private static boolean stripTrailingZerosMethodUnavailable = false;
private static Method stripTrailingZerosMethod = null;
private static boolean canSetScaleNegative = true; // until proved otherwise
private static final Object[] EMPTY_OBJECT_ARRAY = {};
private BigDecimal value;
public static final BigDecimal BIG_DECIMAL_ONE = BigDecimal.valueOf(1);
public static final BigInteger BIG_INTEGER_TEN = BigInteger.valueOf(10);
public static final BigDecimal BIG_DECIMAL_ONE_MILLION = BigDecimal.valueOf(1000000);
public static final DecimalValue ZERO = new DecimalValue(BigDecimal.valueOf(0));
public static final DecimalValue ONE = new DecimalValue(BigDecimal.valueOf(1));
/**
* Constructor supplying a BigDecimal
* @param value the value of the DecimalValue
*/
public DecimalValue(BigDecimal value) {
this.value = stripTrailingZeros(value);
typeLabel = BuiltInAtomicType.DECIMAL;
}
private static final Pattern decimalPattern = Pattern.compile("(\\-|\\+)?((\\.[0-9]+)|([0-9]+(\\.[0-9]*)?))");
/**
* Factory method to construct a DecimalValue from a string
* @param in the value of the DecimalValue
* @param validate true if validation is required; false if the caller knows that the value is valid
* @return the required DecimalValue if the input is valid, or a ValidationFailure encapsulating the error
* message if not.
*/
public static ConversionResult makeDecimalValue(CharSequence in, boolean validate) {
// TODO: tune this method. Do the trimming, validation, and losing trailing zeros in a single pass.
// Use the BigDecimal(integer, scale) constructor.
String trimmed = Whitespace.trimWhitespace(in).toString();
try {
if (validate) {
if (!decimalPattern.matcher(trimmed).matches()) {
ValidationFailure err = new ValidationFailure(
"Cannot convert string " + Err.wrap(trimmed, Err.VALUE) + " to xs:decimal");
err.setErrorCode("FORG0001");
return err;
}
}
BigDecimal val = new BigDecimal(trimmed);
val = stripTrailingZeros(val);
return new DecimalValue(val);
} catch (NumberFormatException err) {
ValidationFailure e = new ValidationFailure(
"Cannot convert string " + Err.wrap(trimmed, Err.VALUE) + " to xs:decimal");
e.setErrorCode("FORG0001");
return e;
}
}
/**
* Test whether a string is castable to a decimal value
* @param in the string to be tested
* @return true if the string has the correct format for a decimal
*/
public static boolean castableAsDecimal(CharSequence in) {
CharSequence trimmed = Whitespace.trimWhitespace(in);
return decimalPattern.matcher(trimmed).matches();
}
/**
* Constructor supplying a double
* @param in the value of the DecimalValue
*/
public DecimalValue(double in) throws ValidationException {
try {
value = stripTrailingZeros(new BigDecimal(in));
} catch (NumberFormatException err) {
// Must be a special value such as NaN or infinity
ValidationException e = new ValidationException(
"Cannot convert double " + Err.wrap(in+"", Err.VALUE) + " to decimal");
e.setErrorCode("FOCA0002");
throw e;
}
typeLabel = BuiltInAtomicType.DECIMAL;
}
/**
* Constructor supplying a long integer
* @param in the value of the DecimalValue
*/
public DecimalValue(long in) {
value = BigDecimal.valueOf(in);
typeLabel = BuiltInAtomicType.DECIMAL;
}
/**
* Create a copy of this atomic value, with a different type label
*
* @param typeLabel the type label of the new copy. The caller is responsible for checking that
* the value actually conforms to this type.
*/
public AtomicValue copyAsSubType(AtomicType typeLabel) {
DecimalValue v = new DecimalValue(value);
v.typeLabel = typeLabel;
return v;
}
/**
* Determine the primitive type of the value. This delivers the same answer as
* getItemType().getPrimitiveItemType(). The primitive types are
* the 19 primitive types of XML Schema, plus xs:integer, xs:dayTimeDuration and xs:yearMonthDuration,
* and xs:untypedAtomic. For external objects, the result is AnyAtomicType.
*/
public BuiltInAtomicType getPrimitiveType() {
return BuiltInAtomicType.DECIMAL;
}
/**
* Remove insignificant trailing zeros (the Java BigDecimal class retains trailing zeros,
* but the XPath 2.0 xs:decimal type does not). The BigDecimal#stripTrailingZeros() method
* was introduced in JDK 1.5: we use it if available, and simulate it if not.
* @param value the supplied value
* @return the value with trailing zeroes removed
*/
private static BigDecimal stripTrailingZeros(BigDecimal value) {
if (stripTrailingZerosMethodUnavailable) {
return stripTrailingZerosFallback(value);
}
try {
if (stripTrailingZerosMethod == null) {
Class[] argTypes = {};
stripTrailingZerosMethod = BigDecimal.class.getMethod("stripTrailingZeros", argTypes);
}
// Note, this designed to avoid repeated searching for the method to invoke. However,
// we still carry the cost of a dynamic invocation using reflection.
Object result = stripTrailingZerosMethod.invoke(value, EMPTY_OBJECT_ARRAY);
return (BigDecimal)result;
} catch (NoSuchMethodException e) {
stripTrailingZerosMethodUnavailable = true;
return stripTrailingZerosFallback(value);
} catch (IllegalAccessException e) {
stripTrailingZerosMethodUnavailable = true;
return stripTrailingZerosFallback(value);
} catch (InvocationTargetException e) {
stripTrailingZerosMethodUnavailable = true;
return stripTrailingZerosFallback(value);
}
}
private static BigDecimal stripTrailingZerosFallback(BigDecimal value) {
// The code below differs from JDK 1.5 stripTrailingZeros in that it does not remove trailing zeros
// from integers, for example 1000 is not changed to 1E3.
int scale = value.scale();
if (scale > 0) {
BigInteger i = value.unscaledValue();
while (true) {
BigInteger[] dr = i.divideAndRemainder(BIG_INTEGER_TEN);
if (dr[1].equals(BigInteger.ZERO)) {
i = dr[0];
scale--;
if (scale==0) {
break;
}
} else {
break;
}
}
if (scale != value.scale()) {
value = new BigDecimal(i, scale);
}
}
return value;
}
/**
* Get the value
*/
public BigDecimal getDecimalValue() {
return value;
}
/**
* Get the hashCode. This must conform to the rules for other NumericValue hashcodes
* @see NumericValue#hashCode
*/
public int hashCode() {
BigDecimal round = value.setScale(0, BigDecimal.ROUND_DOWN);
long value = round.longValue();
if (value > Integer.MIN_VALUE && value < Integer.MAX_VALUE) {
return (int)value;
} else {
return new Double(getDoubleValue()).hashCode();
}
}
public boolean effectiveBooleanValue() {
return value.signum() != 0;
}
/**
* Convert to target data type
*/
public ConversionResult convertPrimitive(BuiltInAtomicType requiredType, boolean validate, XPathContext context) {
switch(requiredType.getFingerprint()) {
case StandardNames.XS_BOOLEAN:
// 0.0 => false, anything else => true
return BooleanValue.get(value.signum()!=0);
case StandardNames.XS_NUMERIC:
case StandardNames.XS_DECIMAL:
case StandardNames.XS_ANY_ATOMIC_TYPE:
return this;
case StandardNames.XS_INTEGER:
return BigIntegerValue.makeIntegerValue(value.toBigInteger());
case StandardNames.XS_UNSIGNED_LONG:
case StandardNames.XS_UNSIGNED_INT:
case StandardNames.XS_UNSIGNED_SHORT:
case StandardNames.XS_UNSIGNED_BYTE:
case StandardNames.XS_NON_POSITIVE_INTEGER:
case StandardNames.XS_NEGATIVE_INTEGER:
case StandardNames.XS_LONG:
case StandardNames.XS_INT:
case StandardNames.XS_SHORT:
case StandardNames.XS_BYTE:
case StandardNames.XS_NON_NEGATIVE_INTEGER:
case StandardNames.XS_POSITIVE_INTEGER:
IntegerValue iv = BigIntegerValue.makeIntegerValue(value.toBigInteger());
return iv.convertPrimitive(requiredType, validate, context);
case StandardNames.XS_DOUBLE:
return new DoubleValue(value.doubleValue());
case StandardNames.XS_FLOAT:
return new FloatValue(value.floatValue());
case StandardNames.XS_STRING:
return new StringValue(getStringValueCS());
case StandardNames.XS_UNTYPED_ATOMIC:
return new UntypedAtomicValue(getStringValueCS());
default:
ValidationFailure err = new ValidationFailure("Cannot convert decimal to " +
requiredType.getDisplayName());
err.setErrorCode("XPTY0004");
return err;
}
}
/**
* Get the value of the item as a CharSequence. This is in some cases more efficient than
* the version of the method that returns a String.
*/
public CharSequence getStringValueCS() {
return decimalToString(value, new FastStringBuffer(20));
}
/**
* Get the canonical lexical representation as defined in XML Schema. This is not always the same
* as the result of casting to a string according to the XPath rules. For xs:decimal, the canonical
* representation always contains a decimal point.
*/
public CharSequence getCanonicalLexicalRepresentation() {
String s = getStringValue();
if (s.indexOf('.') < 0) {
s += ".0";
}
return s;
}
/**
* Get the value as a String
* @return a String representation of the value
*/
public String getStringValue() {
return decimalToString(value, new FastStringBuffer(20)).toString();
}
/**
* Convert a decimal value to a string, using the XPath rules for formatting
* @param value the decimal value to be converted
* @param fsb the FastStringBuffer to which the value is to be appended
* @return the supplied FastStringBuffer, suitably populated
*/
public static FastStringBuffer decimalToString(BigDecimal value, FastStringBuffer fsb) {
// Can't use the plain BigDecimal#toString() under JDK 1.5 because this produces values like "1E-5".
// JDK 1.5 offers BigDecimal#toPlainString() which might do the job directly
int scale = value.scale();
if (scale == 0) {
fsb.append(value.toString());
return fsb;
} else if (scale < 0) {
String s = value.abs().unscaledValue().toString();
if (s.equals("0")) {
fsb.append('0');
return fsb;
}
//FastStringBuffer sb = new FastStringBuffer(s.length() + (-scale) + 2);
if (value.signum() < 0) {
fsb.append('-');
}
fsb.append(s);
for (int i=0; i<(-scale); i++) {
fsb.append('0');
}
return fsb;
} else {
String s = value.abs().unscaledValue().toString();
if (s.equals("0")) {
fsb.append('0');
return fsb;
}
int len = s.length();
//FastStringBuffer sb = new FastStringBuffer(len+1);
if (value.signum() < 0) {
fsb.append('-');
}
if (scale >= len) {
fsb.append("0.");
for (int i=len; i<scale; i++) {
fsb.append('0');
}
fsb.append(s);
} else {
fsb.append(s.substring(0, len-scale));
fsb.append('.');
fsb.append(s.substring(len-scale));
}
return fsb;
}
}
/**
* Negate the value
*/
public NumericValue negate() {
return new DecimalValue(value.negate());
}
/**
* Implement the XPath floor() function
*/
public NumericValue floor() {
return new DecimalValue(value.setScale(0, BigDecimal.ROUND_FLOOR));
}
/**
* Implement the XPath ceiling() function
*/
public NumericValue ceiling() {
return new DecimalValue(value.setScale(0, BigDecimal.ROUND_CEILING));
}
/**
* Implement the XPath round() function
*/
public NumericValue round() {
// The XPath rules say that we should round to the nearest integer, with .5 rounding towards
// positive infinity. Unfortunately this is not one of the rounding modes that the Java BigDecimal
// class supports, so we need different rules depending on the value.
// If the value is positive, we use ROUND_HALF_UP; if it is negative, we use ROUND_HALF_DOWN (here "UP"
// means "away from zero")
switch (value.signum()) {
case -1:
return new DecimalValue(value.setScale(0, BigDecimal.ROUND_HALF_DOWN));
case 0:
return this;
case +1:
return new DecimalValue(value.setScale(0, BigDecimal.ROUND_HALF_UP));
default:
// can't happen
return this;
}
}
/**
* Implement the XPath round-half-to-even() function
*/
public NumericValue roundHalfToEven(int scale) {
if (scale<0 && !canSetScaleNegative) {
// This path is taken on JDK 1.4. But it gives the wrong answer, because
// it ignores the fractional part of the number: so when rounding to a multiple of
// 10, the value 65.05 is rounded to 60 instead of 70.
try {
AtomicValue val = convertPrimitive(BuiltInAtomicType.INTEGER, true, null).asAtomic();
if (val instanceof Int64Value) {
return ((Int64Value)val).roundHalfToEven(scale);
} else {
return ((BigIntegerValue)val).roundHalfToEven(scale);
}
} catch (XPathException err) {
throw new IllegalArgumentException("internal error in integer-decimal conversion");
}
} else {
BigDecimal scaledValue;
try {
scaledValue = value.setScale(scale, BigDecimal.ROUND_HALF_EVEN);
} catch (ArithmeticException e) {
if (scale < 0) {
canSetScaleNegative = false;
return roundHalfToEven(scale);
} else {
throw e;
}
}
return new DecimalValue(stripTrailingZeros(scaledValue));
}
}
/**
* Determine whether the value is negative, zero, or positive
* @return -1 if negative, 0 if zero, +1 if positive, NaN if NaN
*/
public double signum() {
return value.signum();
}
/**
* Determine whether the value is a whole number, that is, whether it compares
* equal to some integer
*/
public boolean isWholeNumber() {
return value.scale()==0 ||
value.compareTo(value.setScale(0, BigDecimal.ROUND_DOWN)) == 0;
}
/**
* Compare the value to another numeric value
*/
public int compareTo(Object other) {
if ((NumericValue.isInteger((NumericValue)other))) {
// deliberately triggers a ClassCastException if other value is the wrong type
try {
return compareTo(((NumericValue)other).convertPrimitive(BuiltInAtomicType.DECIMAL, true, null).asAtomic());
} catch (XPathException err) {
throw new AssertionError("Conversion of integer to decimal should never fail");
}
} else if (other instanceof DecimalValue) {
return value.compareTo(((DecimalValue)other).value);
} else if (other instanceof FloatValue) {
try {
return ((FloatValue)convertPrimitive(BuiltInAtomicType.FLOAT, true, null).asAtomic()).compareTo(other);
} catch (XPathException err) {
throw new AssertionError("Conversion of decimal to float should never fail");
}
} else {
return super.compareTo(other);
}
}
/**
* Compare the value to a long
* @param other the value to be compared with
* @return -1 if this is less, 0 if this is equal, +1 if this is greater or if this is NaN
*/
public int compareTo(long other) {
if (other == 0) {
return value.signum();
}
return value.compareTo(BigDecimal.valueOf(other));
}
/**
* Get a Comparable value that implements the XML Schema ordering comparison semantics for this value.
* Returns null if the value is not comparable according to XML Schema rules. The default implementation
* returns the value itself if it is comparable, or null otherwise. This is modified for types such as
* xs:duration which allow ordering comparisons in XML Schema, but not in XPath.
* <p/>
* <p>In the case of data types that are partially ordered, the returned Comparable extends the standard
* semantics of the compareTo() method by returning the value {@link Value#INDETERMINATE_ORDERING} when there
* is no defined order relationship between two given values.</p>
*/
/**
* Get an object that implements XML Schema comparison semantics
*/
public Comparable getSchemaComparable() {
return new DecimalComparable(this);
}
protected static class DecimalComparable implements Comparable {
protected DecimalValue value;
public DecimalComparable(DecimalValue value) {
this.value = value;
}
public BigDecimal asBigDecimal() {
return value.getDecimalValue();
}
public int compareTo(Object o) {
if (o instanceof DecimalComparable) {
return asBigDecimal().compareTo(((DecimalComparable)o).asBigDecimal());
} else if (o instanceof Int64Value.Int64Comparable) {
return asBigDecimal().compareTo(BigDecimal.valueOf(((Int64Value.Int64Comparable)o).asLong()));
} else if (o instanceof BigIntegerValue.BigIntegerComparable) {
return value.compareTo(new BigDecimal(((BigIntegerValue.BigIntegerComparable)o).asBigInteger()));
} else {
return INDETERMINATE_ORDERING;
}
}
public boolean equals(Object o) {
return compareTo(o) == 0;
}
public int hashCode() {
// Must align with hashCodes for other subtypes of xs:decimal
if (value.isWholeNumber()) {
try {
return value.convertPrimitive(BuiltInAtomicType.INTEGER, true, null).asAtomic()
.getSchemaComparable().hashCode();
} catch (ValidationException e) {
return 12345678; // can't happen
}
}
return value.hashCode();
}
}
/**
* Convert to Java object (for passing to external functions)
*/
public Object convertToJava(Class target, XPathContext context) throws XPathException {
if (target==Object.class || target.isAssignableFrom(BigDecimal.class)) {
return value;
} else if (target.isAssignableFrom(DecimalValue.class)) {
return this;
} else if (target==boolean.class) {
BooleanValue bval = (BooleanValue)convertPrimitive(BuiltInAtomicType.BOOLEAN, true, context).asAtomic();
return Boolean.valueOf(bval.getBooleanValue());
} else if (target==Boolean.class) {
BooleanValue bval = (BooleanValue)convertPrimitive(BuiltInAtomicType.BOOLEAN, true, context).asAtomic();
return Boolean.valueOf(bval.getBooleanValue());
} else if (target==String.class || target==CharSequence.class) {
return getStringValue();
} else if (target==double.class || target==Double.class) {
return new Double(value.doubleValue());
} else if (target==float.class || target==Float.class) {
return new Float(value.floatValue());
} else if (target==long.class || target==Long.class) {
return new Long(value.longValue());
} else if (target==int.class || target==Integer.class) {
return new Integer(value.intValue());
} else if (target==short.class || target==Short.class) {
return new Short(value.shortValue());
} else if (target==byte.class || target==Byte.class) {
return new Byte(value.byteValue());
} else if (target==char.class || target==Character.class) {
return new Character((char)value.intValue());
} else {
Object o = super.convertToJava(target, context);
if (o == null) {
throw new XPathException("Conversion of decimal to " + target.getName() +
" is not supported");
}
return o;
}
}
}
//
// The contents of this file are subject to the Mozilla Public License Version 1.0 (the "License");
// you may not use this file except in compliance with the License. You may obtain a copy of the
// License at http://www.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations under the License.
//
// The Original Code is: all this file except the asStringXT() and zeros() methods (not currently used).
//
// The Initial Developer of the Original Code is Michael H. Kay.
//
// Portions created by (xt) are Copyright (C) (James Clark). All Rights Reserved.
//
// Contributor(s): none.
//