Merge pull request #46 from square/jwilson_0525_enum_ii

Reject unrecognized enum constants with an exception.

moshi/src/main/java/com/squareup/moshi/EnumJsonAdapter.java

@@ -1,62 +0,0 @@
-/*
- * Copyright (C) 2014 Square, Inc.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.squareup.moshi;
-
-import java.io.IOException;
-import java.lang.reflect.AnnotatedElement;
-import java.lang.reflect.Type;
-
-/**
- * Convert Enum types to JSON string values
- *
- * @param <T> Enum class to adapt
- */
-final class EnumJsonAdapter<T extends Enum<T>> extends JsonAdapter<T> {
-  public static final Factory FACTORY = new Factory() {
-    @Override public JsonAdapter<? extends Enum> create(Type type, AnnotatedElement annotations,
-        Moshi moshi) {
-      Class<?> rawType = Types.getRawType(type);
-      if (Enum.class.isAssignableFrom(rawType)) {
-        //noinspection unchecked
-        Class<? extends Enum> enumType = (Class<? extends Enum>) rawType;
-        return new EnumJsonAdapter<>(enumType.getEnumConstants()).nullSafe();
-      }
-      return null;
-    }
-  };
-
-  private final T[] values;
-
-  private EnumJsonAdapter(T[] values) {
-    this.values = values;
-  }
-
-  @Override
-  public T fromJson(JsonReader reader) throws IOException {
-    String name = reader.nextString();
-    for (T value : values) {
-      if (value.name().equals(name)) {
-        return value;
-      }
-    }
-    return null;
-  }
-
-  @Override
-  public void toJson(JsonWriter writer, T value) throws IOException {
-    writer.value(value.name());
-  }
-}

moshi/src/main/java/com/squareup/moshi/Moshi.java

@@ -34,7 +34,6 @@ public final class Moshi {
     List<JsonAdapter.Factory> factories = new ArrayList<>();
     factories.addAll(builder.factories);
     factories.add(StandardJsonAdapters.FACTORY);
-    factories.add(EnumJsonAdapter.FACTORY);
     factories.add(CollectionJsonAdapter.FACTORY);
     factories.add(MapJsonAdapter.FACTORY);
     factories.add(ArrayJsonAdapter.FACTORY);

moshi/src/main/java/com/squareup/moshi/StandardJsonAdapters.java

@@ -18,6 +18,7 @@ package com.squareup.moshi;
 import java.io.IOException;
 import java.lang.reflect.AnnotatedElement;
 import java.lang.reflect.Type;
+import java.util.Arrays;
 
 final class StandardJsonAdapters {
   public static final JsonAdapter.Factory FACTORY = new JsonAdapter.Factory() {
@@ -39,6 +40,12 @@ final class StandardJsonAdapters {
       if (type == Long.class) return LONG_JSON_ADAPTER.nullSafe();
       if (type == Short.class) return SHORT_JSON_ADAPTER.nullSafe();
       if (type == String.class) return STRING_JSON_ADAPTER.nullSafe();
+
+      Class<?> rawType = Types.getRawType(type);
+      if (rawType.isEnum()) {
+        //noinspection unchecked
+        return enumAdapter((Class<? extends Enum>) rawType).nullSafe();
+      }
       return null;
     }
   };
@@ -160,4 +167,23 @@ final class StandardJsonAdapters {
       writer.value(value);
     }
   };
+
+  static <T extends Enum<T>> JsonAdapter<T> enumAdapter(final Class<T> enumType) {
+    return new JsonAdapter<T>() {
+      @Override public T fromJson(JsonReader reader) throws IOException {
+        String name = reader.nextString();
+        try {
+          return Enum.valueOf(enumType, name);
+        } catch (IllegalArgumentException e) {
+          throw new IllegalStateException("Expected one of "
+              + Arrays.toString(enumType.getEnumConstants()) + " but was " + name + " at path "
+              + reader.getPath());
+        }
+      }
+
+      @Override public void toJson(JsonWriter writer, T value) throws IOException {
+        writer.value(value.name());
+      }
+    };
+  }
 }

moshi/src/test/java/com/squareup/moshi/EnumJsonAdapterTest.java

@@ -1,48 +0,0 @@
-/*
- * Copyright (C) 2014 Square, Inc.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.squareup.moshi;
-
-import org.junit.Test;
-
-import static org.assertj.core.api.Assertions.assertThat;
-
-public class EnumJsonAdapterTest {
-  private final Moshi moshi = new Moshi.Builder().build();
-
-  enum Roshambo {
-    ROCK,
-    PAPER,
-    SCISSORS
-  }
-
-  @Test public void basics() throws Exception {
-    JsonAdapter<Roshambo> adapter = moshi.adapter(Roshambo.class).lenient();
-    assertThat(adapter.fromJson("\"ROCK\"")).isEqualTo(Roshambo.ROCK);
-    assertThat(adapter.toJson(Roshambo.PAPER)).isEqualTo("\"PAPER\"");
-  }
-
-  @Test public void invalidInput() throws Exception {
-    JsonAdapter<Roshambo> adapter = moshi.adapter(Roshambo.class).lenient();
-    assertThat(adapter.fromJson("\"Lizard\"")).isNull();
-    assertThat(adapter.fromJson("\"SPOCK\"")).isNull();
-  }
-
-  @Test public void nulls() throws Exception {
-    JsonAdapter<Roshambo> adapter = moshi.adapter(Roshambo.class).lenient();
-    assertThat(adapter.fromJson("null")).isNull();
-    assertThat(adapter.toJson(null)).isEqualTo("null");
-  }
-}

moshi/src/test/java/com/squareup/moshi/MoshiTest.java

@@ -658,6 +658,32 @@ public final class MoshiTest {
     assertThat(adapter.fromJson("[2,3]")).containsExactly(2, 3);
   }
 
+  @Test public void enumAdapter() throws Exception {
+    Moshi moshi = new Moshi.Builder().build();
+    JsonAdapter<Roshambo> adapter = moshi.adapter(Roshambo.class).lenient();
+    assertThat(adapter.fromJson("\"ROCK\"")).isEqualTo(Roshambo.ROCK);
+    assertThat(adapter.toJson(Roshambo.PAPER)).isEqualTo("\"PAPER\"");
+  }
+
+  @Test public void invalidEnum() throws Exception {
+    Moshi moshi = new Moshi.Builder().build();
+    JsonAdapter<Roshambo> adapter = moshi.adapter(Roshambo.class).lenient();
+    try {
+      adapter.fromJson("\"SPOCK\"");
+      fail();
+    } catch (IllegalStateException expected) {
+      assertThat(expected.getMessage())
+          .isEqualTo("Expected one of [ROCK, PAPER, SCISSORS] but was SPOCK at path $");
+    }
+  }
+
+  @Test public void nullEnum() throws Exception {
+    Moshi moshi = new Moshi.Builder().build();
+    JsonAdapter<Roshambo> adapter = moshi.adapter(Roshambo.class).lenient();
+    assertThat(adapter.fromJson("null")).isNull();
+    assertThat(adapter.toJson(null)).isEqualTo("null");
+  }
+
   static class Pizza {
     final int diameter;
     final boolean extraCheese;
@@ -774,4 +800,10 @@ public final class MoshiTest {
       };
     }
   }
+
+  enum Roshambo {
+    ROCK,
+    PAPER,
+    SCISSORS
+  }
 }