Fixing Javadoc and adding Unit Test for the example for #LANG-261.

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/lang/trunk@411898 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/commons/lang/StringUtils.java

@@ -2197,7 +2197,7 @@ public class StringUtils {
      * StringUtils.splitPreserveAllTokens(null, *)         = null
      * StringUtils.splitPreserveAllTokens("", *)           = []
      * StringUtils.splitPreserveAllTokens("a.b.c", '.')    = ["a", "b", "c"]
-     * StringUtils.splitPreserveAllTokens("a..b.c", '.')   = ["a", "b", "c"]
+     * StringUtils.splitPreserveAllTokens("a..b.c", '.')   = ["a", "", "b", "c"]
      * StringUtils.splitPreserveAllTokens("a:b:c", '.')    = ["a:b:c"]
      * StringUtils.splitPreserveAllTokens("a\tb\nc", null) = ["a", "b", "c"]
      * StringUtils.splitPreserveAllTokens("a b c", ' ')    = ["a", "b", "c"]

src/test/org/apache/commons/lang/StringUtilsTest.java

@@ -581,6 +581,16 @@ public class StringUtilsTest extends TestCase {
         assertEquals("b", res[3]);
         assertEquals("c", res[4]);
 
+        // Match example in javadoc
+        {
+          String[] results = null;
+          String[] expectedResults = {"a", "", "b", "c"};
+          results = StringUtils.splitPreserveAllTokens("a..b.c",'.');
+          assertEquals(expectedResults.length, results.length);
+          for (int i = 0; i < expectedResults.length; i++) {
+              assertEquals(expectedResults[i], results[i]);
+          }
+        }
     }
     
     public void testSplitPreserveAllTokens_StringString_StringStringInt() {
@@ -710,6 +720,7 @@ public class StringUtilsTest extends TestCase {
               assertEquals(expectedResults[i], results[i]);
           }
         }
+        
     }
     
     private void innerTestSplitPreserveAllTokens(char separator, String sepStr, char noMatch) {