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/*
*******************************************************************************
* (C) Copyright IBM Corp. and others, 1996-2009 - All Rights Reserved *
* *
* The original version of this source code and documentation is copyrighted *
* and owned by IBM, These materials are provided under terms of a License *
* Agreement between IBM and Sun. This technology is protected by multiple *
* US and International patents. This notice and attribution to IBM may not *
* to removed. *
*******************************************************************************
*/
package sun.text.normalizer;
import java.io.IOException;
import java.util.MissingResourceException;
/**
* <p>
* The UCharacter class provides extensions to the
* <a href="https://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Character.html">
* java.lang.Character</a> class. These extensions provide support for
* more Unicode properties and together with the <a href=../text/UTF16.html>UTF16</a>
* class, provide support for supplementary characters (those with code
* points above U+FFFF).
* Each ICU release supports the latest version of Unicode available at that time.
* </p>
* <p>
* Code points are represented in these API using ints. While it would be
* more convenient in Java to have a separate primitive datatype for them,
* ints suffice in the meantime.
* </p>
* <p>
* To use this class please add the jar file name icu4j.jar to the
* class path, since it contains data files which supply the information used
* by this file.<br>
* E.g. In Windows <br>
* <code>set CLASSPATH=%CLASSPATH%;$JAR_FILE_PATH/ucharacter.jar</code>.<br>
* Otherwise, another method would be to copy the files uprops.dat and
* unames.icu from the icu4j source subdirectory
* <i>$ICU4J_SRC/src/com.ibm.icu.impl.data</i> to your class directory
* <i>$ICU4J_CLASS/com.ibm.icu.impl.data</i>.
* </p>
* <p>
* Aside from the additions for UTF-16 support, and the updated Unicode
* properties, the main differences between UCharacter and Character are:
* <ul>
* <li> UCharacter is not designed to be a char wrapper and does not have
* APIs to which involves management of that single char.<br>
* These include:
* <ul>
* <li> char charValue(),
* <li> int compareTo(java.lang.Character, java.lang.Character), etc.
* </ul>
* <li> UCharacter does not include Character APIs that are deprecated, nor
* does it include the Java-specific character information, such as
* boolean isJavaIdentifierPart(char ch).
* <li> Character maps characters 'A' - 'Z' and 'a' - 'z' to the numeric
* values '10' - '35'. UCharacter also does this in digit and
* getNumericValue, to adhere to the java semantics of these
* methods. New methods unicodeDigit, and
* getUnicodeNumericValue do not treat the above code points
* as having numeric values. This is a semantic change from ICU4J 1.3.1.
* </ul>
* <p>
* Further detail differences can be determined from the program
* <a href="http://source.icu-project.org/repos/icu/icu4j/trunk/src/com/ibm/icu/dev/test/lang/UCharacterCompare.java">
* com.ibm.icu.dev.test.lang.UCharacterCompare</a>
* </p>
* <p>
* In addition to Java compatibility functions, which calculate derived properties,
* this API provides low-level access to the Unicode Character Database.
* </p>
* <p>
* Unicode assigns each code point (not just assigned character) values for
* many properties.
* Most of them are simple boolean flags, or constants from a small enumerated list.
* For some properties, values are strings or other relatively more complex types.
* </p>
* <p>
* For more information see
* "About the Unicode Character Database" (http://www.unicode.org/ucd/)
* and the ICU User Guide chapter on Properties (http://www.icu-project.org/userguide/properties.html).
* </p>
* <p>
* There are also functions that provide easy migration from C/POSIX functions
* like isblank(). Their use is generally discouraged because the C/POSIX
* standards do not define their semantics beyond the ASCII range, which means
* that different implementations exhibit very different behavior.
* Instead, Unicode properties should be used directly.
* </p>
* <p>
* There are also only a few, broad C/POSIX character classes, and they tend
* to be used for conflicting purposes. For example, the "isalpha()" class
* is sometimes used to determine word boundaries, while a more sophisticated
* approach would at least distinguish initial letters from continuation
* characters (the latter including combining marks).
* (In ICU, BreakIterator is the most sophisticated API for word boundaries.)
* Another example: There is no "istitle()" class for titlecase characters.
* </p>
* <p>
* ICU 3.4 and later provides API access for all twelve C/POSIX character classes.
* ICU implements them according to the Standard Recommendations in
* Annex C: Compatibility Properties of UTS #18 Unicode Regular Expressions
* (http://www.unicode.org/reports/tr18/#Compatibility_Properties).
* </p>
* <p>
* API access for C/POSIX character classes is as follows:
* - alpha: isUAlphabetic(c) or hasBinaryProperty(c, UProperty.ALPHABETIC)
* - lower: isULowercase(c) or hasBinaryProperty(c, UProperty.LOWERCASE)
* - upper: isUUppercase(c) or hasBinaryProperty(c, UProperty.UPPERCASE)
* - punct: ((1<<getType(c)) & ((1<<DASH_PUNCTUATION)|(1<<START_PUNCTUATION)|(1<<END_PUNCTUATION)|(1<<CONNECTOR_PUNCTUATION)|(1<<OTHER_PUNCTUATION)|(1<<INITIAL_PUNCTUATION)|(1<<FINAL_PUNCTUATION)))!=0
* - digit: isDigit(c) or getType(c)==DECIMAL_DIGIT_NUMBER
* - xdigit: hasBinaryProperty(c, UProperty.POSIX_XDIGIT)
* - alnum: hasBinaryProperty(c, UProperty.POSIX_ALNUM)
* - space: isUWhiteSpace(c) or hasBinaryProperty(c, UProperty.WHITE_SPACE)
* - blank: hasBinaryProperty(c, UProperty.POSIX_BLANK)
* - cntrl: getType(c)==CONTROL
* - graph: hasBinaryProperty(c, UProperty.POSIX_GRAPH)
* - print: hasBinaryProperty(c, UProperty.POSIX_PRINT)
* </p>
* <p>
* The C/POSIX character classes are also available in UnicodeSet patterns,
* using patterns like [:graph:] or \p{graph}.
* </p>
* <p>
* Note: There are several ICU (and Java) whitespace functions.
* Comparison:
* - isUWhiteSpace=UCHAR_WHITE_SPACE: Unicode White_Space property;
* most of general categories "Z" (separators) + most whitespace ISO controls
* (including no-break spaces, but excluding IS1..IS4 and ZWSP)
* - isWhitespace: Java isWhitespace; Z + whitespace ISO controls but excluding no-break spaces
* - isSpaceChar: just Z (including no-break spaces)
* </p>
* <p>
* This class is not subclassable
* </p>
* @author Syn Wee Quek
* @stable ICU 2.1
* @see com.ibm.icu.lang.UCharacterEnums
*/
public final class UCharacter
{
/**
* Numeric Type constants.
* @see UProperty#NUMERIC_TYPE
* @stable ICU 2.4
*/
public static interface NumericType
{
/**
* @stable ICU 2.4
*/
public static final int DECIMAL = 1;
}
// public data members -----------------------------------------------
/**
* The lowest Unicode code point value.
* @stable ICU 2.1
*/
public static final int MIN_VALUE = UTF16.CODEPOINT_MIN_VALUE;
/**
* The highest Unicode code point value (scalar value) according to the
* Unicode Standard.
* This is a 21-bit value (21 bits, rounded up).<br>
* Up-to-date Unicode implementation of java.lang.Character.MIN_VALUE
* @stable ICU 2.1
*/
public static final int MAX_VALUE = UTF16.CODEPOINT_MAX_VALUE;
/**
* The minimum value for Supplementary code points
* @stable ICU 2.1
*/
public static final int SUPPLEMENTARY_MIN_VALUE =
UTF16.SUPPLEMENTARY_MIN_VALUE;
// public methods ----------------------------------------------------
/**
* Retrieves the numeric value of a decimal digit code point.
* <br>This method observes the semantics of
* <code>java.lang.Character.digit()</code>. Note that this
* will return positive values for code points for which isDigit
* returns false, just like java.lang.Character.
* <br><em>Semantic Change:</em> In release 1.3.1 and
* prior, this did not treat the European letters as having a
* digit value, and also treated numeric letters and other numbers as
* digits.
* This has been changed to conform to the java semantics.
* <br>A code point is a valid digit if and only if:
* <ul>
* <li>ch is a decimal digit or one of the european letters, and
* <li>the value of ch is less than the specified radix.
* </ul>
* @param ch the code point to query
* @param radix the radix
* @return the numeric value represented by the code point in the
* specified radix, or -1 if the code point is not a decimal digit
* or if its value is too large for the radix
* @stable ICU 2.1
*/
public static int digit(int ch, int radix)
{
// when ch is out of bounds getProperty == 0
int props = getProperty(ch);
int value;
if (getNumericType(props) == NumericType.DECIMAL) {
value = UCharacterProperty.getUnsignedValue(props);
} else {
value = getEuropeanDigit(ch);
}
return (0 <= value && value < radix) ? value : -1;
}
/**
* Returns the Bidirection property of a code point.
* For example, 0x0041 (letter A) has the LEFT_TO_RIGHT directional
* property.<br>
* Result returned belongs to the interface
* <a href=UCharacterDirection.html>UCharacterDirection</a>
* @param ch the code point to be determined its direction
* @return direction constant from UCharacterDirection.
* @stable ICU 2.1
*/
public static int getDirection(int ch)
{
return gBdp.getClass(ch);
}
/**
* Returns a code point corresponding to the two UTF16 characters.
* @param lead the lead char
* @param trail the trail char
* @return code point if surrogate characters are valid.
* @exception IllegalArgumentException thrown when argument characters do
* not form a valid codepoint
* @stable ICU 2.1
*/
public static int getCodePoint(char lead, char trail)
{
if (UTF16.isLeadSurrogate(lead) && UTF16.isTrailSurrogate(trail)) {
return UCharacterProperty.getRawSupplementary(lead, trail);
}
throw new IllegalArgumentException("Illegal surrogate characters");
}
/**
* <p>Get the "age" of the code point.</p>
* <p>The "age" is the Unicode version when the code point was first
* designated (as a non-character or for Private Use) or assigned a
* character.
* <p>This can be useful to avoid emitting code points to receiving
* processes that do not accept newer characters.</p>
* <p>The data is from the UCD file DerivedAge.txt.</p>
* @param ch The code point.
* @return the Unicode version number
* @stable ICU 2.6
*/
public static VersionInfo getAge(int ch)
{
if (ch < MIN_VALUE || ch > MAX_VALUE) {
throw new IllegalArgumentException("Codepoint out of bounds");
}
return PROPERTY_.getAge(ch);
}
// private variables -------------------------------------------------
/**
* Database storing the sets of character property
*/
private static final UCharacterProperty PROPERTY_;
/**
* For optimization
*/
private static final char[] PROPERTY_TRIE_INDEX_;
private static final char[] PROPERTY_TRIE_DATA_;
private static final int PROPERTY_INITIAL_VALUE_;
private static final UBiDiProps gBdp;
// block to initialise character property database
static
{
try
{
PROPERTY_ = UCharacterProperty.getInstance();
PROPERTY_TRIE_INDEX_ = PROPERTY_.m_trieIndex_;
PROPERTY_TRIE_DATA_ = PROPERTY_.m_trieData_;
PROPERTY_INITIAL_VALUE_ = PROPERTY_.m_trieInitialValue_;
}
catch (Exception e)
{
throw new MissingResourceException(e.getMessage(),"","");
}
UBiDiProps bdp;
try {
bdp=UBiDiProps.getSingleton();
} catch(IOException e) {
bdp=UBiDiProps.getDummy();
}
gBdp=bdp;
}
/**
* Shift to get numeric type
*/
private static final int NUMERIC_TYPE_SHIFT_ = 5;
/**
* Mask to get numeric type
*/
private static final int NUMERIC_TYPE_MASK_ = 0x7 << NUMERIC_TYPE_SHIFT_;
// private methods ---------------------------------------------------
/**
* Getting the digit values of characters like 'A' - 'Z', normal,
* half-width and full-width. This method assumes that the other digit
* characters are checked by the calling method.
* @param ch character to test
* @return -1 if ch is not a character of the form 'A' - 'Z', otherwise
* its corresponding digit will be returned.
*/
private static int getEuropeanDigit(int ch) {
if ((ch > 0x7a && ch < 0xff21)
|| ch < 0x41 || (ch > 0x5a && ch < 0x61)
|| ch > 0xff5a || (ch > 0xff3a && ch < 0xff41)) {
return -1;
}
if (ch <= 0x7a) {
// ch >= 0x41 or ch < 0x61
return ch + 10 - ((ch <= 0x5a) ? 0x41 : 0x61);
}
// ch >= 0xff21
if (ch <= 0xff3a) {
return ch + 10 - 0xff21;
}
// ch >= 0xff41 && ch <= 0xff5a
return ch + 10 - 0xff41;
}
/**
* Gets the numeric type of the property argument
* @param props 32 bit property
* @return the numeric type
*/
private static int getNumericType(int props)
{
return (props & NUMERIC_TYPE_MASK_) >> NUMERIC_TYPE_SHIFT_;
}
/**
* Gets the property value at the index.
* This is optimized.
* Note this is alittle different from CharTrie the index m_trieData_
* is never negative.
* This is a duplicate of UCharacterProperty.getProperty. For optimization
* purposes, this method calls the trie data directly instead of through
* UCharacterProperty.getProperty.
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