Feature : add EnumFeature.WRITE_ENUMS_TO_LOWERCASE #3053 #3054 (#3776)

FasterXML · Feb 10, 2023 · 0f0d04c · 0f0d04c
1 parent 6c8c151
commit 0f0d04c
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Showing 4 changed files with 48 additions and 2 deletions.
diff --git a/src/main/java/com/fasterxml/jackson/databind/cfg/EnumFeature.java b/src/main/java/com/fasterxml/jackson/databind/cfg/EnumFeature.java
@@ -22,8 +22,16 @@ public enum EnumFeature implements DatatypeFeature
  *
  * @since 2.15
  */
- READ_ENUM_KEYS_USING_INDEX(false)
- ;
+ READ_ENUM_KEYS_USING_INDEX(false),
+
+ /**
+ * Feature that determines standard serialization mechanism used for
+ * Enum values: if enabled, return value of <code>Enum.name().toLowerCase()</code>
+ * is used; if disabled, return value of <code>Enum.name()</code> is used.
+ *<p>
+ * Feature is disabled by default.
+ */
+ WRITE_ENUMS_TO_LOWERCASE(false);
 
  private final static int FEATURE_INDEX = DatatypeFeatures.FEATURE_INDEX_ENUM;
 

diff --git a/src/main/java/com/fasterxml/jackson/databind/util/EnumValues.java b/src/main/java/com/fasterxml/jackson/databind/util/EnumValues.java
@@ -4,6 +4,7 @@
 
 import com.fasterxml.jackson.core.SerializableString;
 import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.databind.cfg.EnumFeature;
 import com.fasterxml.jackson.databind.cfg.MapperConfig;
 
 /**
@@ -56,6 +57,9 @@ public static EnumValues constructFromName(MapperConfig<?> config, Class<Enum<?>
  if (name == null) {
  name = en.name();
  }
+ if (config.isEnabled(EnumFeature.WRITE_ENUMS_TO_LOWERCASE)) {
+ name = name.toLowerCase();
+ }
  textual[en.ordinal()] = config.compileString(name);
  }
  return construct(enumClass, textual);

diff --git a/src/test/java/com/fasterxml/jackson/databind/ser/jdk/EnumSerializationTest.java b/src/test/java/com/fasterxml/jackson/databind/ser/jdk/EnumSerializationTest.java
@@ -8,6 +8,7 @@
 import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import com.fasterxml.jackson.databind.cfg.EnumFeature;
 import com.fasterxml.jackson.databind.jsontype.TypeSerializer;
 import com.fasterxml.jackson.databind.module.SimpleModule;
 import com.fasterxml.jackson.databind.ser.std.StdSerializer;
@@ -330,6 +331,25 @@ public void testEnumWithJsonKey() throws Exception
  = Collections.singletonMap(EnumWithJsonKey.A, EnumWithJsonKey.B);
  assertEquals(a2q("{'key:a':'value:b'}"), MAPPER.writeValueAsString(input2));
  }
+
+ public void testEnumFeature_WRITE_ENUMS_TO_LOWERCASE_isDisabledByDefault() {
+ ObjectReader READER = MAPPER.reader();
+ assertFalse(READER.isEnabled(EnumFeature.WRITE_ENUMS_TO_LOWERCASE));
+ assertFalse(READER.without(EnumFeature.WRITE_ENUMS_TO_LOWERCASE)
+ .isEnabled(EnumFeature.WRITE_ENUMS_TO_LOWERCASE));
+ }
+
+ public void testEnumFeature_WRITE_ENUMS_TO_LOWERCASE() throws Exception {
+ ObjectMapper m = jsonMapperBuilder()
+ .configure(EnumFeature.WRITE_ENUMS_TO_LOWERCASE, true)
+ .build();
+ assertEquals("\"b\"", m.writeValueAsString(TestEnum.B));
+
+ // [databind#749] but should also be able to dynamically disable
+ assertEquals("\"B\"",
+ m.writer().without(EnumFeature.WRITE_ENUMS_TO_LOWERCASE)
+ .writeValueAsString(LowerCaseEnum.B));
+ }
 }
 
 // [JACKSON-757], non-inner enum

diff --git a/src/test/java/com/fasterxml/jackson/databind/util/EnumValuesTest.java b/src/test/java/com/fasterxml/jackson/databind/util/EnumValuesTest.java
@@ -6,6 +6,7 @@
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationConfig;
 import com.fasterxml.jackson.databind.SerializationFeature;
+import com.fasterxml.jackson.databind.cfg.EnumFeature;
 
 public class EnumValuesTest extends BaseMapTest
 {
@@ -64,4 +65,17 @@ public void testEnumResolver()
  assertEquals(ABC.B, enums.get(1));
  assertEquals(ABC.C, enums.get(2));
  }
+
+ @SuppressWarnings("unchecked")
+ public void testConstructFromNameLowerCased() {
+ SerializationConfig cfg = MAPPER.getSerializationConfig()
+ .with(EnumFeature.WRITE_ENUMS_TO_LOWERCASE);
+ Class<Enum<?>> enumClass = (Class<Enum<?>>)(Class<?>) ABC.class;
+ EnumValues values = EnumValues.construct(cfg, enumClass);
+ assertEquals("a", values.serializedValueFor(ABC.A).toString());
+ assertEquals("b", values.serializedValueFor(ABC.B).toString());
+ assertEquals("c", values.serializedValueFor(ABC.C).toString());
+ assertEquals(3, values.values().size());
+ assertEquals(3, values.internalMap().size());
+ }
 }