ICU-23009 Enhance MeasureUnit handling for constant denominators

- Updated MeasureUnit class to allow constant denominators for both COMPOUND and SINGLE complexities. - Modified error handling to throw exceptions for unsupported complexities. - Added new test cases in MeasureUnitTest to validate constant denominators, including edge cases and non-acceptable identifiers. This change improves the robustness of the MeasureUnit functionality and expands the test coverage for constant denominators.
unicode-org · Jan 20, 2025 · 1e8b0cb · 1e8b0cb
1 parent 9e03b30
commit 1e8b0cb
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Showing 2 changed files with 42 additions and 5 deletions.
diff --git a/icu4j/main/common_tests/src/test/java/com/ibm/icu/dev/test/format/MeasureUnitTest.java b/icu4j/main/common_tests/src/test/java/com/ibm/icu/dev/test/format/MeasureUnitTest.java
@@ -1334,6 +1334,7 @@ class ConstantDenominatorTestCase {
                 new ConstantDenominatorTestCase("second-per-1000-minute", 1000),
                 new ConstantDenominatorTestCase("gram-per-1000-kilogram", 1000),
                 new ConstantDenominatorTestCase("meter-per-100", 100),
+                // Test for constant denominators that are powers of 10
                 new ConstantDenominatorTestCase("portion-per-1", 1),
                 new ConstantDenominatorTestCase("portion-per-10", 10),
                 new ConstantDenominatorTestCase("portion-per-100", 100),
@@ -1353,16 +1354,23 @@ class ConstantDenominatorTestCase {
                 new ConstantDenominatorTestCase("portion-per-10000000000000000", 10000000000000000L),
                 new ConstantDenominatorTestCase("portion-per-100000000000000000", 100000000000000000L),
                 new ConstantDenominatorTestCase("portion-per-1000000000000000000", 1000000000000000000L),
+                // Test for constant denominators that are represented as scientific notation
+                // numbers.
                 new ConstantDenominatorTestCase("portion-per-1e9", 1000000000L),
                 new ConstantDenominatorTestCase("portion-per-1E9", 1000000000L),
                 new ConstantDenominatorTestCase("portion-per-10e9", 10000000000L),
                 new ConstantDenominatorTestCase("portion-per-10E9", 10000000000L),
                 new ConstantDenominatorTestCase("portion-per-1e10", 10000000000L),
                 new ConstantDenominatorTestCase("portion-per-1E10", 10000000000L),
                 new ConstantDenominatorTestCase("portion-per-1e3-kilometer", 1000),
+                // Test for constant denominators that are randomely selected.
                 new ConstantDenominatorTestCase("liter-per-12345-kilometer", 12345),
                 new ConstantDenominatorTestCase("per-1000-kilometer", 1000),
                 new ConstantDenominatorTestCase("liter-per-1000-kiloliter", 1000),
+                // Test for constant denominators that gives 0.
+                        new ConstantDenominatorTestCase("meter", 0),
+                new ConstantDenominatorTestCase("meter-per-second", 0),
+                new ConstantDenominatorTestCase("meter-per-square-second", 0),
                 // NOTE: The following constant denominator should be 0. However, since
                 // `100-kilometer` is treated as a unit in CLDR,
                 // the unit does not have a constant denominator.
@@ -1379,7 +1387,35 @@ class ConstantDenominatorTestCase {
             MeasureUnit unit = MeasureUnit.forIdentifier(testCase.identifier);
             assertEquals("Constant denominator for " + testCase.identifier, testCase.expectedConstantDenominator,
                     unit.getConstantDenominator());
-            assertEquals("Complexity for " + testCase.identifier, Complexity.COMPOUND, unit.getComplexity());
+            assertTrue("Complexity for " + testCase.identifier,
+                    unit.getComplexity() == Complexity.COMPOUND || unit.getComplexity() == Complexity.SINGLE);
+        }
+    }
+
+    @Test
+    public void TestNonAcceptableConstantDenominator() {
+        class NonAcceptableConstantDenominatorTestCase {
+            String identifier;
+
+            NonAcceptableConstantDenominatorTestCase(String identifier) {
+                this.identifier = identifier;
+            }
+        }
+
+        List<NonAcceptableConstantDenominatorTestCase> testCases = Arrays.asList(
+                new NonAcceptableConstantDenominatorTestCase("meter-and-second"),
+                new NonAcceptableConstantDenominatorTestCase("meter-per--20--second"),
+                new NonAcceptableConstantDenominatorTestCase("meter-per-1000-1e9-second"),
+                new NonAcceptableConstantDenominatorTestCase("meter-per-1e20-second"));
+
+        for (NonAcceptableConstantDenominatorTestCase testCase : testCases) {
+            try {
+                MeasureUnit unit = MeasureUnit.forIdentifier(testCase.identifier);
+                unit.getConstantDenominator();
+                Assert.fail("An IllegalArgumentException must be thrown");
+            } catch (Exception e) {
+                continue;
+            }
         }
     }
 

diff --git a/icu4j/main/core/src/main/java/com/ibm/icu/util/MeasureUnit.java b/icu4j/main/core/src/main/java/com/ibm/icu/util/MeasureUnit.java
@@ -555,7 +555,7 @@ public MeasurePrefix getPrefix() {
      * @draft ICU 77
      */
     public MeasureUnit withConstantDenominator(long denominator) {
-        if (this.getComplexity() == Complexity.MIXED) {
+        if (this.getComplexity() != Complexity.COMPOUND && this.getComplexity() != Complexity.SINGLE) {
             throw new UnsupportedOperationException(
                     "Constant denominator can only be applied to COMPOUND & SINGLE units");
         }
@@ -581,7 +581,7 @@ public MeasureUnit withConstantDenominator(long denominator) {
      * zero.</li>
      * </ul>
      * <p>
-     * This method is applicable only to COMPOUND units. If invoked on a SINGLE or
+     * This method is applicable only to COMPOUND & SINGLE units. If invoked on a
      * MIXED unit, an exception will be thrown.
      * For further details, refer to {@link Complexity}.
      * <p>
@@ -593,8 +593,9 @@ public MeasureUnit withConstantDenominator(long denominator) {
      * @draft ICU 77
      */
     public long getConstantDenominator() {
-        if (this.getComplexity() != Complexity.COMPOUND) {
-            throw new UnsupportedOperationException("Constant denominator is only supported for COMPOUND units");
+        if (this.getComplexity() != Complexity.COMPOUND && this.getComplexity() != Complexity.SINGLE) {
+            throw new UnsupportedOperationException(
+                    "Constant denominator is only supported for COMPOUND & SINGLE units");
         }
 
         if (this.measureUnitImpl == null) {