New posts for Spring and Hibernate

2026-11-06 01:05:27 +05:30
parent 51913ad9d4
commit dc13293046
136 changed files with 5268 additions and 0 deletions
@@ -0,0 +1,50 @@
+# Null handling: IGNORE vs the default on a patch, and RETURN_DEFAULT on whole objects and collections
+
+
+--- patch(): nullValuePropertyMappingStrategy = IGNORE, applied with a patch whose components are all null ---
+before: [email protected], nickname=ash, roles=[USER], address=12 Park Road/Pune/411001
+after : [email protected], nickname=ash, roles=[USER], address=12 Park Road/Pune/411001
+
+--- replace(): the default strategy (SET_TO_NULL), same all-null patch ---
+before: [email protected], nickname=ash, roles=[USER], address=12 Park Road/Pune/411001
+after : email=null, nickname=null, roles=null, address=null
+
+--- whole objects and collections: OrderMapper (default) vs LenientOrderMapper (RETURN_DEFAULT) ---
+strict.toDto(null)          : null
+lenient.toDto(null)         : OrderDto[id=null, status=null, placedAt=null, lines=null, total=null]
+strict  order, lines = null : lines=null
+lenient order, lines = null : lines=[]
+strict.toDtos(null)         : null
+
+--- the generated patch() (IGNORE): every assignment is guarded ---
+    public void patch(CustomerPatch patch, Customer customer) {
+        if ( patch == null ) {
+            return;
+        }
+
+        if ( patch.email() != null ) {
+            customer.setEmail( patch.email() );
+        }
+        if ( patch.nickname() != null ) {
+            customer.setNickname( patch.nickname() );
+        }
+        if ( patch.address() != null ) {
+            if ( customer.getAddress() == null ) {
+                customer.setAddress( new Address() );
+            }
+            addressMapper.update( patch.address(), customer.getAddress() );
+        }
+        if ( customer.getRoles() != null ) {
+            Set<String> set = patch.roles();
+            if ( set != null ) {
+                customer.getRoles().clear();
+                customer.getRoles().addAll( set );
+            }
+        }
+        else {
+            Set<String> set = patch.roles();
+            if ( set != null ) {
+                customer.setRoles( new LinkedHashSet<String>( set ) );
+            }
+        }
+    }