com.ibm.icu.util

Class CodePointMap

java.lang.Object

com.ibm.icu.util.CodePointMap

All Implemented Interfaces:

Iterable<CodePointMap.Range>

Direct Known Subclasses:

CodePointTrie, MutableCodePointTrie

public abstract class CodePointMap
extends Object
implements Iterable<CodePointMap.Range>

Abstract map from Unicode code points (U+0000..U+10FFFF) to integer values. This does not implement java.util.Map.

Status:

Stable ICU 63.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CodePointMap.Range Range iteration result data.
static class	CodePointMap.RangeOption Selectors for how getRange() should report value ranges overlapping with surrogates.
class	CodePointMap.StringIterator Iterates over code points of a string and fetches map values.
static interface	CodePointMap.ValueFilter Callback function interface: Modifies a map value.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	CodePointMap() Protected no-args constructor.

Method Summary

Modifier and Type	Method and Description
abstract int	get(int c) Returns the value for a code point as stored in the map, with range checking.
boolean	getRange(int start, CodePointMap.RangeOption option, int surrogateValue, CodePointMap.ValueFilter filter, CodePointMap.Range range) Sets the range object to a range of code points beginning with the start parameter.
abstract boolean	getRange(int start, CodePointMap.ValueFilter filter, CodePointMap.Range range) Sets the range object to a range of code points beginning with the start parameter.
Iterator<CodePointMap.Range>	iterator() Convenience iterator over same-map-value code point ranges.
CodePointMap.StringIterator	stringIterator(CharSequence s, int sIndex) Returns an iterator (not a java.util.Iterator) over code points of a string for fetching map values.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

CodePointMap

protected CodePointMap()

Protected no-args constructor.

Status:

Stable ICU 63.

Method Detail

get

public abstract int get(int c)

Returns the value for a code point as stored in the map, with range checking. Returns an implementation-defined error value if c is not in the range 0..U+10FFFF.

Parameters:

c - the code point

Returns:

the map value, or an implementation-defined error value if the code point is not in the range 0..U+10FFFF

Status:

Stable ICU 63.

getRange

public abstract boolean getRange(int start,
                                 CodePointMap.ValueFilter filter,
                                 CodePointMap.Range range)

Sets the range object to a range of code points beginning with the start parameter. The range start is the same as the start input parameter (even if there are preceding code points that have the same value). The range end is the last code point such that all those from start to there have the same value. Returns false if start is not 0..U+10FFFF. Can be used to efficiently iterate over all same-value ranges in a map. (This is normally faster than iterating over code points and get()ting each value, but may be much slower than a data structure that stores ranges directly.)

If the CodePointMap.ValueFilter parameter is not null, then the value to be delivered is passed through that filter, and the return value is the end of the range where all values are modified to the same actual value. The value is unchanged if that parameter is null.

Example:

 int start = 0;
 CodePointMap.Range range = new CodePointMap.Range();
 while (map.getRange(start, null, range)) {
     int end = range.getEnd();
     int value = range.getValue();
     // Work with the range start..end and its value.
     start = end + 1;
 }
 

Parameters:

start - range start

filter - an object that may modify the map data value, or null if the values from the map are to be used unmodified

range - the range object that will be set to the code point range and value

Returns:

true if start is 0..U+10FFFF; otherwise no new range is fetched

Status:

Stable ICU 63.

getRange

public boolean getRange(int start,
                        CodePointMap.RangeOption option,
                        int surrogateValue,
                        CodePointMap.ValueFilter filter,
                        CodePointMap.Range range)

Sets the range object to a range of code points beginning with the start parameter. The range start is the same as the start input parameter (even if there are preceding code points that have the same value). The range end is the last code point such that all those from start to there have the same value. Returns false if start is not 0..U+10FFFF.

Same as the simpler getRange(int, ValueFilter, Range) but optionally modifies the range if it overlaps with surrogate code points.

Parameters:

start - range start

option - defines whether surrogates are treated normally, or as having the surrogateValue; usually CodePointMap.RangeOption.NORMAL

surrogateValue - value for surrogates; ignored if option==CodePointMap.RangeOption.NORMAL

filter - an object that may modify the map data value, or null if the values from the map are to be used unmodified

range - the range object that will be set to the code point range and value

Returns:

true if start is 0..U+10FFFF; otherwise no new range is fetched

Status:

Stable ICU 63.

iterator

public Iterator<CodePointMap.Range> iterator()

Convenience iterator over same-map-value code point ranges. Same as looping over all ranges with getRange(int, ValueFilter, Range) without filtering. Adjacent ranges have different map values.

The iterator always returns the same Range object.

Specified by:

iterator in interface Iterable<CodePointMap.Range>

Returns:

a Range iterator

Status:

Stable ICU 63.

stringIterator

public CodePointMap.StringIterator stringIterator(CharSequence s,
                                                  int sIndex)

Returns an iterator (not a java.util.Iterator) over code points of a string for fetching map values.

Parameters:

s - string to iterate over

sIndex - string index where the iteration will start

Returns:

the iterator

Status:

Stable ICU 63.