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.
  • Constructor Details

    • CodePointMap

      protected CodePointMap()
      Protected no-args constructor.
  • Method Details

    • 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
    • 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
    • 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
    • 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
    • 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