UNITSOFMEASUREMENT-186: Change ServiceProvider.available() to Collection

Task-Url: https://java.net/jira/browse/UNITSOFMEASUREMENT-186

Author: keilw

src/main/java/javax/measure/spi/ServiceProvider.java

@@ -44,7 +44,7 @@
  * <p>
  * All the methods in this class are safe for use by multiple concurrent threads.
  *
- * @version 0.9.1, June 14, 2016
+ * @version 0.9.2, June 15, 2016
  * @author Werner Keil
  * @author Martin Desruisseaux
  */
@@ -127,12 +127,12 @@ public int compare(ServiceProvider p1, ServiceProvider p2) {
   }
 
   /**
-   * Returns all available service providers.
+   * Returns the list of available service providers.
    *
    * @return all available service providers.
    */
-  public static ServiceProvider[] available() {
-    return getProviders().clone();
+  public static List<ServiceProvider> available() {
+    return Arrays.asList(getProviders()); // .clone();
   }
 
   /**

src/test/java/javax/measure/spi/ServiceProviderTest.java

@@ -51,7 +51,7 @@ public void testSetDefault_Null() {
    */
   @Test
   public void testGetAndSetDefault() {
-    assertEquals(0, ServiceProvider.available().length);
+    assertEquals(0, ServiceProvider.available().size());
     try {
       ServiceProvider.current();
       fail("Expected no ServiceProvider before we set one.");
@@ -62,7 +62,7 @@ public void testGetAndSetDefault() {
     assertNull("Expected no ServiceProvider before we set one.", ServiceProvider.setCurrent(testProv));
     assertSame("Setting the same ServiceProvider twice should be a no-op.", testProv, ServiceProvider.setCurrent(testProv));
     assertSame(testProv, ServiceProvider.current());
-    assertArrayEquals(new ServiceProvider[] { testProv }, ServiceProvider.available());
+    assertArrayEquals(new ServiceProvider[] { testProv }, ServiceProvider.available().toArray());
   }
 
   private static final class TestServiceProvider extends ServiceProvider {