Create separate class for callback

Author: alex-semenyuk

spring-data-mongodb/src/main/java/org/baeldung/event/CascadeCallback.java

@@ -0,0 +1,53 @@
+package org.baeldung.event;
+
+import java.lang.reflect.Field;
+
+import org.baeldung.annotation.CascadeSave;
+import org.springframework.data.mongodb.core.MongoOperations;
+import org.springframework.data.mongodb.core.mapping.DBRef;
+import org.springframework.util.ReflectionUtils;
+
+public class CascadeCallback implements ReflectionUtils.FieldCallback {
+    
+    private Object source;
+    private MongoOperations mongoOperations;
+    
+    public CascadeCallback(final Object source, final MongoOperations mongoOperations) {
+        this.source = source;
+        this.setMongoOperations(mongoOperations);
+    }
+
+    @Override
+    public void doWith(Field field) throws IllegalArgumentException, IllegalAccessException {
+        ReflectionUtils.makeAccessible(field);
+
+        if (field.isAnnotationPresent(DBRef.class) && field.isAnnotationPresent(CascadeSave.class)) {
+            final Object fieldValue = field.get(getSource());
+
+            if (fieldValue != null) {
+                FieldCallback callback = new FieldCallback();
+
+                ReflectionUtils.doWithFields(fieldValue.getClass(), callback);
+
+                getMongoOperations().save(fieldValue);
+            }
+        }
+
+    }
+
+    public Object getSource() {
+        return source;
+    }
+
+    public void setSource(Object source) {
+        this.source = source;
+    }
+
+    public MongoOperations getMongoOperations() {
+        return mongoOperations;
+    }
+
+    public void setMongoOperations(MongoOperations mongoOperations) {
+        this.mongoOperations = mongoOperations;
+    }
+}

spring-data-mongodb/src/main/java/org/baeldung/event/CascadeSaveMongoEventListener.java

@@ -1,37 +1,17 @@
 package org.baeldung.event;
 
-import org.baeldung.annotation.CascadeSave;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.data.mongodb.core.MongoOperations;
-import org.springframework.data.mongodb.core.mapping.DBRef;
 import org.springframework.data.mongodb.core.mapping.event.AbstractMongoEventListener;
 import org.springframework.util.ReflectionUtils;
 
-import java.lang.reflect.Field;
-
 public class CascadeSaveMongoEventListener extends AbstractMongoEventListener<Object> {
+    
     @Autowired
     private MongoOperations mongoOperations;
-
+  
     @Override
     public void onBeforeConvert(final Object source) {
-        ReflectionUtils.doWithFields(source.getClass(), new ReflectionUtils.FieldCallback() {
-
-            public void doWith(Field field) throws IllegalArgumentException, IllegalAccessException {
-                ReflectionUtils.makeAccessible(field);
-
-                if (field.isAnnotationPresent(DBRef.class) && field.isAnnotationPresent(CascadeSave.class)) {
-                    final Object fieldValue = field.get(source);
-
-                    if (fieldValue != null) {
-                        FieldCallback callback = new FieldCallback();
-
-                        ReflectionUtils.doWithFields(fieldValue.getClass(), callback);
-
-                        mongoOperations.save(fieldValue);
-                    }
-                }
-            }
-        });
+        ReflectionUtils.doWithFields(source.getClass(), new CascadeCallback(source, mongoOperations));
     }
-}
+}