OAK-11556 : removed usage of Guava's Iterables.getFirst with oak-commons API (#2146)

* OAK-11556 : removed usage of Guava's Iterables.getFirst with Streams.findFirst()

* OAK-11556 : removed usage of Guava's Iterables.getFirst with oak-commons

---------

Co-authored-by: Rishabh Kumar <diam@adobe.com>

Author: rishabhdaim

oak-core/src/test/java/org/apache/jackrabbit/oak/plugins/index/property/PropertyIndexTest.java

@@ -1041,7 +1041,7 @@ protected Validator getRootValidator(NodeState before, NodeState after, CommitIn
         assertTrue(indexedState.exists());
         Iterable<String> values = indexedState.getStrings("entry");
         assertEquals(1, IterableUtils.size(values));
-        assertEquals("/content", Iterables.getFirst(values, null));
+        assertEquals("/content", IterableUtils.getFirst(values, null));
 
         Mount roMount = mip.getMountByName("foo");
         assertFalse(getNode(indexed, "/oak:index/foo/" + getNodeForMount(roMount)).exists());

oak-jcr/src/test/java/org/apache/jackrabbit/oak/jcr/OakRepositoryStub.java

@@ -26,6 +26,7 @@
 import org.apache.jackrabbit.guava.common.collect.Iterables;
 
 import org.apache.jackrabbit.oak.commons.FixturesHelper.Fixture;
+import org.apache.jackrabbit.oak.commons.collections.IterableUtils;
 import org.apache.jackrabbit.test.NotExecutableException;
 import org.apache.jackrabbit.test.RepositoryStub;
 import org.apache.jackrabbit.test.RepositoryStubException;
@@ -65,7 +66,7 @@ public Principal getUnknownPrincipal(Session session)
     private static RepositoryStub newDelegate(Properties settings)
             throws RepositoryException {
         // use first fixture for stub with segment-tar as default
-        Fixture f = Iterables.getFirst(getFixtures(), Fixture.SEGMENT_TAR);
+        Fixture f = IterableUtils.getFirst(getFixtures(), Fixture.SEGMENT_TAR);
         if (f == Fixture.DOCUMENT_MEM) {
             return new OakDocumentMemRepositoryStub(settings);
         } else if (f == Fixture.DOCUMENT_RDB) {

oak-store-document/src/main/java/org/apache/jackrabbit/oak/plugins/document/VersionGCSupport.java

@@ -306,7 +306,7 @@ protected static boolean isDefaultNoBranchSplitNewerThan(NodeDocument doc,
         if (doc.getSplitDocType() != SplitDocType.DEFAULT_NO_BRANCH) {
             return false;
         }
-        Revision r = Iterables.getFirst(doc.getAllChanges(), null);
+        Revision r = IterableUtils.getFirst(doc.getAllChanges(), null);
         return r != null && sweepRevs.isRevisionNewer(r);
     }
 }

oak-store-document/src/test/java/org/apache/jackrabbit/oak/plugins/document/DocumentNodeStoreSweepTest.java

@@ -25,6 +25,7 @@
 import org.apache.jackrabbit.guava.common.collect.Iterables;
 import org.apache.jackrabbit.oak.api.CommitFailedException;
 import org.apache.jackrabbit.oak.commons.PathUtils;
+import org.apache.jackrabbit.oak.commons.collections.IterableUtils;
 import org.apache.jackrabbit.oak.plugins.document.memory.MemoryDocumentStore;
 import org.apache.jackrabbit.oak.plugins.document.util.Utils;
 import org.apache.jackrabbit.oak.spi.state.NodeBuilder;
@@ -260,7 +261,7 @@ public <T extends Document> List<T> query(Collection<T> collection,
         Revision r = null;
         for (NodeDocument d : Utils.getAllDocuments(store)) {
             if (d.getPath().toString().startsWith("/node-")) {
-                r = Iterables.getFirst(d.getAllChanges(), null);
+                r = IterableUtils.getFirst(d.getAllChanges(), null);
                 break;
             }
         }

oak-store-spi/src/main/java/org/apache/jackrabbit/oak/plugins/memory/PropertyStates.java

@@ -32,6 +32,7 @@
 import org.apache.jackrabbit.oak.api.Blob;
 import org.apache.jackrabbit.oak.api.PropertyState;
 import org.apache.jackrabbit.oak.api.Type;
+import org.apache.jackrabbit.oak.commons.collections.IterableUtils;
 import org.apache.jackrabbit.oak.plugins.value.Conversions;
 import org.apache.jackrabbit.oak.plugins.value.OakValue;
 import org.apache.jackrabbit.util.ISO8601;
@@ -89,7 +90,7 @@ public static PropertyState createProperty(
             String name, Iterable<Value> values)
             throws RepositoryException {
         int type = PropertyType.STRING;
-        Value first = Iterables.getFirst(values, null);
+        Value first = IterableUtils.getFirst(values, null);
         if (first != null) {
             type = first.getType();
         }