Allow empty rules in a RuleBasedCollator.

This is allowed by the CLDR specification, and we were already allowing
most forms of empty rules, just not the zero-length string.

Change-Id: I3c2a020aac23e54f8044defbfe2e2a5b600e454c

2 files changed, 4 insertions, 13 deletions

diff --git a/harmony-tests/src/test/java/org/apache/harmony/tests/java/text/RuleBasedCollatorTest.java b/harmony-tests/src/test/java/org/apache/harmony/tests/java/text/RuleBasedCollatorTest.java
index 89dfea9..f5a8057 100644
--- a/harmony-tests/src/test/java/org/apache/harmony/tests/java/text/RuleBasedCollatorTest.java
+++ b/harmony-tests/src/test/java/org/apache/harmony/tests/java/text/RuleBasedCollatorTest.java
@@ -250,14 +250,9 @@ public class RuleBasedCollatorTest extends TestCase {
     }
   }
 
-  public void testEmptyStringException() {
-    //Regression for HARMONY-241
-    try {
-      new RuleBasedCollator("");
-      fail();
-    } catch (ParseException e) {
-      assertEquals("java.text.ParseException", e.getClass().getName());
-      assertEquals(0, e.getErrorOffset());
-    }
+  public void testEmptyRules() throws Exception {
+    new RuleBasedCollator("");
+    new RuleBasedCollator(" ");
+    new RuleBasedCollator("# This is a comment.");
   }
 }
diff --git a/luni/src/main/java/java/text/RuleBasedCollator.java b/luni/src/main/java/java/text/RuleBasedCollator.java
index db1da5f..90dbd86 100644
--- a/luni/src/main/java/java/text/RuleBasedCollator.java
+++ b/luni/src/main/java/java/text/RuleBasedCollator.java
@@ -101,10 +101,6 @@ public class RuleBasedCollator extends Collator {
         if (rules == null) {
             throw new NullPointerException("rules == null");
         }
-        // icu4c is fine with empty rules, but the RI isn't.
-        if (rules.isEmpty()) {
-            throw new ParseException("empty rules", 0);
-        }
         try {
             icuColl = new RuleBasedCollatorICU(rules);
         } catch (Exception e) {