Rewrite addCodePointsToSet as toCodePointSet

by overloading with a version that takes a collection

Author: yawnoc

CHANGELOG.md

@@ -3,6 +3,7 @@
 
 ## [Unreleased]
 
+- Rewrote `addCodePointsToSet` as `toCodePointSet`
 - Tweaked Help > Miscellaneous explanations
   - Put Function column before Action column in table
   - Moved 'Retract keyboard' explanation into table

app/src/main/java/io/github/yawnoc/strokeinput/StrokeInputService.java

@@ -878,7 +878,6 @@ private List<String> computeCandidateList(final String strokeDigitSequence)
       exactMatchCandidateList = Collections.emptyList();
     }
 
-    final Set<Integer> prefixMatchCodePointSet = new HashSet<>();
     final Collection<String> prefixMatchCharactersCollection =
             charactersFromStrokeDigitSequence
               .subMap(
@@ -888,10 +887,7 @@ private List<String> computeCandidateList(final String strokeDigitSequence)
               .values();
 
     final long addCodePointsStartMilliseconds = System.currentTimeMillis();
-    for (final String characters : prefixMatchCharactersCollection)
-    {
-      Stringy.addCodePointsToSet(characters, prefixMatchCodePointSet);
-    }
+    final Set<Integer> prefixMatchCodePointSet = Stringy.toCodePointSet(prefixMatchCharactersCollection);
     final long addCodePointsEndMilliseconds = System.currentTimeMillis();
     if (BuildConfig.DEBUG)
     {

app/src/main/java/io/github/yawnoc/utilities/Stringy.java

@@ -8,6 +8,8 @@
 package io.github.yawnoc.utilities;
 
 import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 import java.util.regex.Pattern;
@@ -66,17 +68,36 @@ public static List<Integer> toCodePointList(final String string)
   }
 
   /*
-    Add the (unicode) code points of a string to a set
+    Convert a string to a set of (unicode) code points.
   */
-  public static void addCodePointsToSet(final String string, final Set<Integer> set)
+  public static Set<Integer> toCodePointSet(final String string)
   {
+    final Set<Integer> codePointSet = new HashSet<>();
+
     final int charCount = string.length();
     for (int charIndex = 0; charIndex < charCount;)
     {
       final int codePoint = string.codePointAt(charIndex);
-      set.add(codePoint);
+      codePointSet.add(codePoint);
       charIndex += Character.charCount(codePoint);
     }
+
+    return codePointSet;
+  }
+
+  /*
+    Convert a collection of strings to a set of (unicode) code points.
+  */
+  public static Set<Integer> toCodePointSet(final Collection<String> stringCollection)
+  {
+    final Set<Integer> codePointSet = new HashSet<>();
+
+    for (final String string : stringCollection)
+    {
+      codePointSet.addAll(toCodePointSet(string));
+    }
+
+    return codePointSet;
   }
 
   /*

app/src/test/java/io/github/yawnoc/utilities/StringyTest.java

@@ -12,10 +12,8 @@
 import org.junit.Test;
 
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
-import java.util.Set;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
@@ -87,18 +85,17 @@ public void toCodePointList_isCorrect()
   }
 
   @Test
-  public void addCodePointsToSet_isCorrect()
+  public void toCodePointSet_isCorrect()
   {
-    final int SOME_CODE_POINT = 0x1234;
-    final Set<Integer> commonsCodePointSet = new HashSet<>(Collections.singletonList(SOME_CODE_POINT));
-    Stringy.addCodePointsToSet("天下為公", commonsCodePointSet);
-    assertEquals(commonsCodePointSet, new HashSet<>(Arrays.asList(SOME_CODE_POINT, 0x5929, 0x4E0B, 0x70BA, 0x516C)));
-    
-    final Set<Integer> asciiFullCodePointSet = new HashSet<>();
-    Stringy.addCodePointsToSet(ASCII_FULL_STRING, asciiFullCodePointSet);
-    assertEquals(asciiFullCodePointSet, new HashSet<>(ASCII_CODE_POINT_RANGE));
+    assertEquals(Stringy.toCodePointSet(ASCII_FULL_STRING), new HashSet<>(ASCII_CODE_POINT_RANGE));
+    assertEquals(Stringy.toCodePointSet("天下為公"), new HashSet<>(Arrays.asList(0x5929, 0x4E0B, 0x70BA, 0x516C)));
+
+    assertEquals(
+      Stringy.toCodePointSet(Arrays.asList("ABC", "天地玄黃", "BCD")),
+      new HashSet<>(Arrays.asList(0x41, 0x42, 0x43, 0x5929, 0x5730, 0x7384, 0x9EC3, 0x44))
+    );
   }
-  
+
   @Test
   public void toString_isCorrect()
   {