Package com.ibm.icu.text

Class UnicodeSetIterator

  • public class UnicodeSetIterator
extends Object
    UnicodeSetIterator iterates over the contents of a UnicodeSet. It iterates over either code points or code point ranges. After all code points or ranges have been returned, it returns the multicharacter strings of the UnicodSet, if any.

    To iterate over code points and multicharacter strings, use a loop like this: 

     for (UnicodeSetIterator it = new UnicodeSetIterator(set); it.next();) {
   processString(it.getString());
 }

    To iterate over code point ranges, use a loop like this: 

     for (UnicodeSetIterator it = new UnicodeSetIterator(set); it.nextRange();) {
   if (it.codepoint != UnicodeSetIterator.IS_STRING) {
     processCodepointRange(it.codepoint, it.codepointEnd);
   } else {
     processString(it.getString());
   }
 }

    Warning: For speed, UnicodeSet iteration does not check for concurrent modification. Do not alter the UnicodeSet while iterating.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      int codepoint
      Current code point, or the special value IS_STRING, if the iterator points to a string.
      int codepointEnd
      When iterating over ranges using nextRange(), codepointEnd contains the inclusive end of the iteration range, if codepoint !
      protected int endElement
      Deprecated.
      This API is ICU internal only.
      static int IS_STRING
      Value of codepoint if the iterator points to a string.
      protected int nextElement
      Deprecated.
      This API is ICU internal only.
      String string
      If codepoint == IS_STRING, then string points to the current string.

    • Field Detail

      • IS_STRING

        public static int IS_STRING
        Value of codepoint if the iterator points to a string. If codepoint == IS_STRING, then examine string for the current iteration result.

      • codepoint

        public int codepoint
        Current code point, or the special value IS_STRING, if the iterator points to a string.

      • codepointEnd

        public int codepointEnd
        When iterating over ranges using nextRange(), codepointEnd contains the inclusive end of the iteration range, if codepoint != IS_STRING. If iterating over code points using next(), or if codepoint == IS_STRING, then the value of codepointEnd is undefined.

      • string

        public String string
        If codepoint == IS_STRING, then string points to the current string. If codepoint != IS_STRING, the value of string is undefined.

      • endElement

        @Deprecated
protected int endElement
        Deprecated.
        This API is ICU internal only.

      • nextElement

        @Deprecated
protected int nextElement
        Deprecated.
        This API is ICU internal only.

    • Constructor Detail

      • UnicodeSetIterator

        public UnicodeSetIterator​(UnicodeSet set)
        Create an iterator over the given set.
        Parameters:
        set - set to iterate over

      • UnicodeSetIterator

        public UnicodeSetIterator()
        Create an iterator over nothing. next() and nextRange() return false. This is a convenience constructor allowing the target to be set later.

    • Method Detail

      • next

        public boolean next()
        Returns the next element in the set, either a single code point or a string. If there are no more elements in the set, return false. If codepoint == IS_STRING, the value is a string in the string field. Otherwise the value is a single code point in the codepoint field.

        The order of iteration is all code points in sorted order, followed by all strings sorted order. codepointEnd is undefined after calling this method. string is undefined unless codepoint == IS_STRING. Do not mix calls to next() and nextRange() without calling reset() between them. The results of doing so are undefined.

        Warning: For speed, UnicodeSet iteration does not check for concurrent modification. Do not alter the UnicodeSet while iterating.

        Returns:
        true if there was another element in the set and this object contains the element.

      • nextRange

        public boolean nextRange()
        Returns the next element in the set, either a code point range or a string. If there are no more elements in the set, return false. If codepoint == IS_STRING, the value is a string in the string field. Otherwise the value is a range of one or more code points from codepoint to codepointeEnd inclusive.

        The order of iteration is all code points ranges in sorted order, followed by all strings sorted order. Ranges are disjoint and non-contiguous. string is undefined unless codepoint == IS_STRING. Do not mix calls to next() and nextRange() without calling reset() between them. The results of doing so are undefined.

        Returns:
        true if there was another element in the set and this object contains the element.

      • reset

        public void reset​(UnicodeSet uset)
        Sets this iterator to visit the elements of the given set and resets it to the start of that set. The iterator is valid only so long as set is valid.
        Parameters:
        uset - the set to iterate over.

      • reset

        public void reset()
        Resets this iterator to the start of the set.

      • getString

        public String getString()
        Gets the current string from the iterator. Only use after calling next(), not nextRange().

      • loadRange

        @Deprecated
protected void loadRange​(int aRange)
        Deprecated.
        This API is ICU internal only.