1/* 2****************************************************************************** 3* Copyright (C) 1996-2010, International Business Machines Corporation and * 4* others. All Rights Reserved. * 5****************************************************************************** 6*/ 7 8package com.ibm.icu.util; 9 10/** 11 * <p>Interface for enabling iteration over sets of <int index, int value>, 12 * where index is the sorted integer index in ascending order and value, its 13 * associated integer value.</p> 14 * <p>The result for each iteration is the consecutive range of 15 * <int index, int value> with the same value. Result is represented by 16 * <start, limit, value> where</p> 17 * <ul> 18 * <li> start is the starting integer of the result range 19 * <li> limit is 1 after the maximum integer that follows start, such that 20 * all integers between start and (limit - 1), inclusive, have the same 21 * associated integer value. 22 * <li> value is the integer value that all integers from start to (limit - 1) 23 * share in common. 24 * </ul> 25 * <p> 26 * Hence value(start) = value(start + 1) = .... = value(start + n) = .... = 27 * value(limit - 1). However value(start -1) != value(start) and 28 * value(limit) != value(start). 29 * </p> 30 * <p>Most implementations will be created by factory methods, such as the 31 * character type iterator in UCharacter.getTypeIterator. See example below. 32 * </p> 33 * Example of use:<br> 34 * <pre> 35 * RangeValueIterator iterator = UCharacter.getTypeIterator(); 36 * RangeValueIterator.Element result = new RangeValueIterator.Element(); 37 * while (iterator.next(result)) { 38 * System.out.println("Codepoint \\u" + 39 * Integer.toHexString(result.start) + 40 * " to codepoint \\u" + 41 * Integer.toHexString(result.limit - 1) + 42 * " has the character type " + result.value); 43 * } 44 * </pre> 45 * @author synwee 46 * @stable ICU 2.6 47 */ 48public interface RangeValueIterator 49{ 50 // public inner class --------------------------------------------- 51 52 /** 53 * Return result wrapper for com.ibm.icu.util.RangeValueIterator. 54 * Stores the start and limit of the continous result range and the 55 * common value all integers between [start, limit - 1] has. 56 * @stable ICU 2.6 57 */ 58 public class Element 59 { 60 // public data member --------------------------------------------- 61 62 /** 63 * Starting integer of the continuous result range that has the same 64 * value 65 * @stable ICU 2.6 66 */ 67 public int start; 68 /** 69 * (End + 1) integer of continuous result range that has the same 70 * value 71 * @stable ICU 2.6 72 */ 73 public int limit; 74 /** 75 * Gets the common value of the continous result range 76 * @stable ICU 2.6 77 */ 78 public int value; 79 80 // public constructor -------------------------------------------- 81 82 /** 83 * Empty default constructor to make javadoc happy 84 * @stable ICU 2.4 85 */ 86 public Element() 87 { 88 } 89 } 90 91 // public methods ------------------------------------------------- 92 93 /** 94 * <p>Returns the next maximal result range with a common value and returns 95 * true if we are not at the end of the iteration, false otherwise.</p> 96 * <p>If this returns a false, the contents of elements will not 97 * be updated.</p> 98 * @param element for storing the result range and value 99 * @return true if we are not at the end of the iteration, false otherwise. 100 * @see Element 101 * @stable ICU 2.6 102 */ 103 public boolean next(Element element); 104 105 /** 106 * Resets the iterator to the beginning of the iteration. 107 * @stable ICU 2.6 108 */ 109 public void reset(); 110} 111