Java Doc for UCharacter.java in  » 6.0-JDK-Modules-sun » text » sun » text » normalizer » Java Source Code / Java DocumentationJava Source Code and Java Documentation

The UCharacter class provides extensions to the java.lang.Character class. These extensions provide support for Unicode 3.2 properties and together with the UTF16 class, provide support for supplementary characters (those with code points above U+FFFF).

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.

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.
E.g. In Windows
set CLASSPATH=%CLASSPATH%;$JAR_FILE_PATH/ucharacter.jar.
Otherwise, another method would be to copy the files uprops.dat and unames.icu from the icu4j source subdirectory $ICU4J_SRC/src/com.ibm.icu.impl.data to your class directory $ICU4J_CLASS/com.ibm.icu.impl.data.

Aside from the additions for UTF-16 support, and the updated Unicode 3.1 properties, the main differences between UCharacter and Character are:

• UCharacter is not designed to be a char wrapper and does not have APIs to which involves management of that single char.
  These include:
  • char charValue(),
  • int compareTo(java.lang.Character, java.lang.Character), etc.
• UCharacter does not include Character APIs that are deprecated, not does it include the Java-specific character information, such as boolean isJavaIdentifierPart(char ch).
• 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.

Further detail differences can be determined from the program com.ibm.icu.dev.test.lang.UCharacterCompare

This class is not subclassable

Get the "age" of the code point.

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.

This can be useful to avoid emitting code points to receiving processes that do not accept newer characters.

The data is from the UCD file DerivedAge.txt.

Gets the property value for an Unicode property type of a code point.

Get the numeric value for a Unicode code point as defined in the Unicode Character Database.

A "double" return type is necessary because some numeric values are fractions, negative, or too large for int.

For characters without any numeric values in the Unicode Character Database, this function will return NO_NUMERIC_VALUE.

API Change: In release 2.2 and prior, this API has a return type int and returns -1 when the argument ch does not have a corresponding numeric value.

• ch is a decimal digit or one of the european letters, and
• the value of ch is less than the specified radix.

Get the "age" of the code point.

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.

This can be useful to avoid emitting code points to receiving processes that do not accept newer characters.

The data is from the UCD file DerivedAge.txt.

Gets the property value for an Unicode property type of a code point. Also returns binary and mask property values.

Unicode, especially in version 3.2, defines many more properties than the original set in UnicodeData.txt.

The properties APIs are intended to reflect Unicode properties as defined in the Unicode Character Database (UCD) and Unicode Technical Reports (UTR). For details about the properties see http://www.unicode.org/.

For names of Unicode properties see the UCD file PropertyAliases.txt.

 Sample usage:
 int ea = UCharacter.getIntPropertyValue(c, UProperty.EAST_ASIAN_WIDTH);
 int ideo = UCharacter.getIntPropertyValue(c, UProperty.IDEOGRAPHIC);
 boolean b = (ideo == 1) ? true : false; 
 

Get the numeric value for a Unicode code point as defined in the Unicode Character Database.

A "double" return type is necessary because some numeric values are fractions, negative, or too large for int.

For characters without any numeric values in the Unicode Character Database, this function will return NO_NUMERIC_VALUE.

API Change: In release 2.2 and prior, this API has a return type int and returns -1 when the argument ch does not have a corresponding numeric value. This has been changed to synch with ICU4C