Replace nullable return with Optional

Author: SpaiR

src/main/java/io/github/spair/byond/dmi/comparator/DmiDiffEntry.java

@@ -5,6 +5,8 @@
 import lombok.Data;
 import lombok.Setter;
 
+import java.util.Optional;
+
 @Data
 @Setter(AccessLevel.PACKAGE)
 @SuppressWarnings("WeakerAccess")
@@ -30,4 +32,12 @@ public class DmiDiffEntry {
             throw new IllegalArgumentException("Original and Modified sprites are null. State name: " + stateName);
         }
     }
+
+    public Optional<DmiSprite> getOldSprite() {
+        return Optional.ofNullable(oldSprite);
+    }
+
+    public Optional<DmiSprite> getNewSprite() {
+        return Optional.ofNullable(newSprite);
+    }
 }

src/test/java/io/github/spair/byond/dmi/comparator/DmiComparatorTest.java

@@ -14,6 +14,7 @@
 
 import static org.junit.Assert.*;
 
+@SuppressWarnings("OptionalGetWithoutIsPresent")
 public class DmiComparatorTest {
 
     private static final String ROLLERBED_ORIGINAL_PATH = "src/test/resources/rollerbed_original.dmi";
@@ -41,31 +42,31 @@ public void testCompareWhenNotSame() {
 
             switch (expectedEntry.getStatus()) {
                 case CREATED:
-                    assertNull(compareToEntry.getOldSprite());
-                    assertNotNull(expectedEntry.getNewSprite());
-                    assertNotNull(compareToEntry.getNewSprite());
+                    assertFalse(compareToEntry.getOldSprite().isPresent());
+                    assertTrue(expectedEntry.getNewSprite().isPresent());
+                    assertTrue(compareToEntry.getNewSprite().isPresent());
 
-                    assertEquals(expectedEntry.getNewSprite().getDir(), compareToEntry.getNewSprite().getDir());
-                    assertEquals(expectedEntry.getNewSprite().getFrameNum(), compareToEntry.getNewSprite().getFrameNum());
+                    assertEquals(expectedEntry.getNewSprite().get().getDir(), compareToEntry.getNewSprite().get().getDir());
+                    assertEquals(expectedEntry.getNewSprite().get().getFrameNum(), compareToEntry.getNewSprite().get().getFrameNum());
                     break;
                 case MODIFIED:
-                    assertNotNull(expectedEntry.getOldSprite());
-                    assertNotNull(compareToEntry.getOldSprite());
-                    assertNotNull(expectedEntry.getNewSprite());
-                    assertNotNull(compareToEntry.getNewSprite());
-
-                    assertEquals(expectedEntry.getOldSprite().getDir(), compareToEntry.getOldSprite().getDir());
-                    assertEquals(expectedEntry.getOldSprite().getFrameNum(), compareToEntry.getOldSprite().getFrameNum());
-                    assertEquals(expectedEntry.getNewSprite().getDir(), compareToEntry.getNewSprite().getDir());
-                    assertEquals(expectedEntry.getNewSprite().getFrameNum(), compareToEntry.getNewSprite().getFrameNum());
+                    assertTrue(expectedEntry.getOldSprite().isPresent());
+                    assertTrue(compareToEntry.getOldSprite().isPresent());
+                    assertTrue(expectedEntry.getNewSprite().isPresent());
+                    assertTrue(compareToEntry.getNewSprite().isPresent());
+
+                    assertEquals(expectedEntry.getOldSprite().get().getDir(), compareToEntry.getOldSprite().get().getDir());
+                    assertEquals(expectedEntry.getOldSprite().get().getFrameNum(), compareToEntry.getOldSprite().get().getFrameNum());
+                    assertEquals(expectedEntry.getNewSprite().get().getDir(), compareToEntry.getNewSprite().get().getDir());
+                    assertEquals(expectedEntry.getNewSprite().get().getFrameNum(), compareToEntry.getNewSprite().get().getFrameNum());
                     break;
                 case DELETED:
-                    assertNull(compareToEntry.getNewSprite());
-                    assertNotNull(expectedEntry.getOldSprite());
-                    assertNotNull(compareToEntry.getOldSprite());
+                    assertFalse(compareToEntry.getNewSprite().isPresent());
+                    assertTrue(expectedEntry.getOldSprite().isPresent());
+                    assertTrue(compareToEntry.getOldSprite().isPresent());
 
-                    assertEquals(expectedEntry.getOldSprite().getDir(), compareToEntry.getOldSprite().getDir());
-                    assertEquals(expectedEntry.getOldSprite().getFrameNum(), compareToEntry.getOldSprite().getFrameNum());
+                    assertEquals(expectedEntry.getOldSprite().get().getDir(), compareToEntry.getOldSprite().get().getDir());
+                    assertEquals(expectedEntry.getOldSprite().get().getFrameNum(), compareToEntry.getOldSprite().get().getFrameNum());
                     break;
             }
         }