Give FieldNamingStrategy the ability to return multiple String names

google · Nov 17, 2024 · 0d769c7 · 0d769c7
1 parent 78caa5e
commit 0d769c7
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Showing 5 changed files with 40 additions and 7 deletions.
diff --git a/gson/src/main/java/com/google/gson/FieldNamingStrategy.java b/gson/src/main/java/com/google/gson/FieldNamingStrategy.java
@@ -17,6 +17,8 @@
 package com.google.gson;
 
 import java.lang.reflect.Field;
+import java.util.Collections;
+import java.util.List;
 
 /**
  * A mechanism for providing custom field naming in Gson. This allows the client code to translate
@@ -33,8 +35,18 @@ public interface FieldNamingStrategy {
    * Translates the field name into its JSON field name representation.
    *
    * @param f the field object that we are translating
-   * @return the translated field name.
+   * @return the list of possible translated field names.
    * @since 1.3
    */
   public String translateName(Field f);
+
+  /**
+   * Translates the field name into its JSON field alternative names representation.
+   *
+   * @param f the field object that we are translating
+   * @return the list of possible translated field names.
+   */
+  default List<String> translateToAlternateNames(Field f) {
+    return Collections.emptyList();
+  }
 }
diff --git a/gson/src/main/java/com/google/gson/internal/bind/ReflectiveTypeAdapterFactory.java b/gson/src/main/java/com/google/gson/internal/bind/ReflectiveTypeAdapterFactory.java
@@ -86,8 +86,10 @@ private boolean includeField(Field f, boolean serialize) {
   private List<String> getFieldNames(Field f) {
     SerializedName annotation = f.getAnnotation(SerializedName.class);
     if (annotation == null) {
-      String name = fieldNamingPolicy.translateName(f);
-      return Collections.singletonList(name);
+      String fieldName = fieldNamingPolicy.translateName(f);
+      List<String> fieldNames = new ArrayList<>(fieldNamingPolicy.translateToAlternateNames(f));
+      fieldNames.add(fieldName);
+      return fieldNames;
     }
 
     String serializedName = annotation.value();

diff --git a/gson/src/test/java/com/google/gson/FieldNamingPolicyTest.java b/gson/src/test/java/com/google/gson/FieldNamingPolicyTest.java
@@ -103,8 +103,7 @@ class Dummy {
       for (FieldNamingPolicy policy : policies) {
         // Should ignore default Locale
         assertWithMessage("Unexpected conversion for %s", policy)
-            .that(policy.translateName(field))
-            .matches(expected);
+            .that(policy.translateName(field)).matches(expected);
       }
     } finally {
       Locale.setDefault(oldLocale);
@@ -142,8 +141,7 @@ class Dummy {
       for (FieldNamingPolicy policy : policies) {
         // Should ignore default Locale
         assertWithMessage("Unexpected conversion for %s", policy)
-            .that(policy.translateName(field))
-            .matches(expected);
+            .that(policy.translateName(field)).matches(expected);
       }
     } finally {
       Locale.setDefault(oldLocale);

diff --git a/gson/src/test/java/com/google/gson/functional/Java17RecordTest.java b/gson/src/test/java/com/google/gson/functional/Java17RecordTest.java
@@ -39,6 +39,7 @@
 import com.google.gson.stream.JsonWriter;
 import java.io.IOException;
 import java.lang.reflect.Type;
+
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;

diff --git a/gson/src/test/java/com/google/gson/functional/NamingPolicyTest.java b/gson/src/test/java/com/google/gson/functional/NamingPolicyTest.java
@@ -26,6 +26,7 @@
 import com.google.gson.common.TestTypes.ClassWithSerializedNameFields;
 import com.google.gson.common.TestTypes.StringWrapper;
 import java.lang.reflect.Field;
+import java.util.List;
 import java.util.Locale;
 import org.junit.Before;
 import org.junit.Test;
@@ -237,6 +238,25 @@ public void testAtSignInSerializedName() {
     assertThat(new Gson().toJson(new AtName())).isEqualTo("{\"@foo\":\"bar\"}");
   }
 
+  @Test
+  public void testGsonWithAlternateNamesDeserialiation() {
+    Gson gson = builder.setFieldNamingStrategy(new FieldNamingStrategy() {
+
+      @Override
+      public String translateName(Field f) {
+        return "badname";
+      }
+
+      @Override
+      public List<String> translateToAlternateNames(Field f) {
+        return List.of("SomeConstantStringInstanceField");
+      }
+    }).create();
+    String target = "{\"SomeConstantStringInstanceField\":\"someValue\"}";
+    StringWrapper deserializedObject = gson.fromJson(target, StringWrapper.class);
+    assertThat(deserializedObject.someConstantStringInstanceField).isEqualTo("someValue");
+  }
+
   static final class AtName {
     @SerializedName("@foo")
     String f = "bar";