gson-comments/gson/src/test/java/com/google/gson/functional/EnumTest.java

295 lines
9.1 KiB
Java

/*
* Copyright (C) 2008 Google 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.google.gson.functional;
import static com.google.common.truth.Truth.assertThat;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonParseException;
import com.google.gson.JsonPrimitive;
import com.google.gson.JsonSerializationContext;
import com.google.gson.JsonSerializer;
import com.google.gson.annotations.SerializedName;
import com.google.gson.common.MoreAsserts;
import com.google.gson.reflect.TypeToken;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.EnumMap;
import java.util.EnumSet;
import java.util.Map;
import java.util.Set;
import org.junit.Before;
import org.junit.Test;
/**
* Functional tests for Java 5.0 enums.
*
* @author Inderjeet Singh
* @author Joel Leitch
*/
public class EnumTest {
private Gson gson;
@Before
public void setUp() throws Exception {
gson = new Gson();
}
@Test
public void testTopLevelEnumSerialization() {
String result = gson.toJson(MyEnum.VALUE1);
assertThat(result).isEqualTo('"' + MyEnum.VALUE1.toString() + '"');
}
@Test
public void testTopLevelEnumDeserialization() {
MyEnum result = gson.fromJson('"' + MyEnum.VALUE1.toString() + '"', MyEnum.class);
assertThat(result).isEqualTo(MyEnum.VALUE1);
}
@Test
public void testCollectionOfEnumsSerialization() {
Type type = new TypeToken<Collection<MyEnum>>() {}.getType();
Collection<MyEnum> target = new ArrayList<>();
target.add(MyEnum.VALUE1);
target.add(MyEnum.VALUE2);
String expectedJson = "[\"VALUE1\",\"VALUE2\"]";
String actualJson = gson.toJson(target);
assertThat(actualJson).isEqualTo(expectedJson);
actualJson = gson.toJson(target, type);
assertThat(actualJson).isEqualTo(expectedJson);
}
@Test
public void testCollectionOfEnumsDeserialization() {
Type type = new TypeToken<Collection<MyEnum>>() {}.getType();
String json = "[\"VALUE1\",\"VALUE2\"]";
Collection<MyEnum> target = gson.fromJson(json, type);
MoreAsserts.assertContains(target, MyEnum.VALUE1);
MoreAsserts.assertContains(target, MyEnum.VALUE2);
}
@Test
public void testClassWithEnumFieldSerialization() {
ClassWithEnumFields target = new ClassWithEnumFields();
assertThat(gson.toJson(target)).isEqualTo(target.getExpectedJson());
}
@Test
public void testClassWithEnumFieldDeserialization() {
String json = "{value1:'VALUE1',value2:'VALUE2'}";
ClassWithEnumFields target = gson.fromJson(json, ClassWithEnumFields.class);
assertThat(target.value1).isEqualTo(MyEnum.VALUE1);
assertThat(target.value2).isEqualTo(MyEnum.VALUE2);
}
private static enum MyEnum {
VALUE1, VALUE2
}
private static class ClassWithEnumFields {
private final MyEnum value1 = MyEnum.VALUE1;
private final MyEnum value2 = MyEnum.VALUE2;
public String getExpectedJson() {
return "{\"value1\":\"" + value1 + "\",\"value2\":\"" + value2 + "\"}";
}
}
/**
* Test for issue 226.
*/
@Test
public void testEnumSubclass() {
assertThat(Roshambo.ROCK.getClass()).isAssignableTo(Roshambo.class);
assertThat(gson.toJson(Roshambo.ROCK)).isEqualTo("\"ROCK\"");
assertThat(gson.toJson(EnumSet.allOf(Roshambo.class))).isEqualTo("[\"ROCK\",\"PAPER\",\"SCISSORS\"]");
assertThat(gson.fromJson("\"ROCK\"", Roshambo.class)).isEqualTo(Roshambo.ROCK);
assertThat(EnumSet.allOf(Roshambo.class)).isEqualTo(
gson.fromJson("[\"ROCK\",\"PAPER\",\"SCISSORS\"]", new TypeToken<Set<Roshambo>>() {}.getType())
);
}
@Test
public void testEnumSubclassWithRegisteredTypeAdapter() {
gson = new GsonBuilder()
.registerTypeHierarchyAdapter(Roshambo.class, new MyEnumTypeAdapter())
.create();
assertThat(Roshambo.ROCK.getClass()).isAssignableTo(Roshambo.class);
assertThat(gson.toJson(Roshambo.ROCK)).isEqualTo("\"123ROCK\"");
assertThat(gson.toJson(EnumSet.allOf(Roshambo.class))).isEqualTo("[\"123ROCK\",\"123PAPER\",\"123SCISSORS\"]");
assertThat(gson.fromJson("\"123ROCK\"", Roshambo.class)).isEqualTo(Roshambo.ROCK);
assertThat(EnumSet.allOf(Roshambo.class)).isEqualTo(
gson.fromJson("[\"123ROCK\",\"123PAPER\",\"123SCISSORS\"]", new TypeToken<Set<Roshambo>>() {}.getType())
);
}
@Test
public void testEnumSubclassAsParameterizedType() {
Collection<Roshambo> list = new ArrayList<>();
list.add(Roshambo.ROCK);
list.add(Roshambo.PAPER);
String json = gson.toJson(list);
assertThat(json).isEqualTo("[\"ROCK\",\"PAPER\"]");
Type collectionType = new TypeToken<Collection<Roshambo>>() {}.getType();
Collection<Roshambo> actualJsonList = gson.fromJson(json, collectionType);
MoreAsserts.assertContains(actualJsonList, Roshambo.ROCK);
MoreAsserts.assertContains(actualJsonList, Roshambo.PAPER);
}
@Test
public void testEnumCaseMapping() {
assertThat(gson.fromJson("\"boy\"", Gender.class)).isEqualTo(Gender.MALE);
assertThat(gson.toJson(Gender.MALE, Gender.class)).isEqualTo("\"boy\"");
}
@Test
public void testEnumSet() {
EnumSet<Roshambo> foo = EnumSet.of(Roshambo.ROCK, Roshambo.PAPER);
String json = gson.toJson(foo);
assertThat(json).isEqualTo("[\"ROCK\",\"PAPER\"]");
Type type = new TypeToken<EnumSet<Roshambo>>() {}.getType();
EnumSet<Roshambo> bar = gson.fromJson(json, type);
assertThat(bar).containsExactly(Roshambo.ROCK, Roshambo.PAPER).inOrder();
assertThat(bar).doesNotContain(Roshambo.SCISSORS);;
}
@Test
public void testEnumMap() {
EnumMap<MyEnum, String> map = new EnumMap<>(MyEnum.class);
map.put(MyEnum.VALUE1, "test");
String json = gson.toJson(map);
assertThat(json).isEqualTo("{\"VALUE1\":\"test\"}");
Type type = new TypeToken<EnumMap<MyEnum, String>>() {}.getType();
EnumMap<?, ?> actualMap = gson.fromJson("{\"VALUE1\":\"test\"}", type);
Map<?, ?> expectedMap = Collections.singletonMap(MyEnum.VALUE1, "test");
assertThat(actualMap).isEqualTo(expectedMap);
}
private enum Roshambo {
ROCK {
@Override Roshambo defeats() {
return SCISSORS;
}
},
PAPER {
@Override Roshambo defeats() {
return ROCK;
}
},
SCISSORS {
@Override Roshambo defeats() {
return PAPER;
}
};
abstract Roshambo defeats();
}
private static class MyEnumTypeAdapter
implements JsonSerializer<Roshambo>, JsonDeserializer<Roshambo> {
@Override public JsonElement serialize(Roshambo src, Type typeOfSrc, JsonSerializationContext context) {
return new JsonPrimitive("123" + src.name());
}
@Override public Roshambo deserialize(JsonElement json, Type classOfT, JsonDeserializationContext context)
throws JsonParseException {
return Roshambo.valueOf(json.getAsString().substring(3));
}
}
private enum Gender {
@SerializedName("boy")
MALE,
@SerializedName("girl")
FEMALE
}
@Test
public void testEnumClassWithFields() {
assertThat(gson.toJson(Color.RED)).isEqualTo("\"RED\"");
assertThat(gson.fromJson("RED", Color.class).value).isEqualTo("red");
assertThat(gson.fromJson("BLUE", Color.class).index).isEqualTo(2);
}
private enum Color {
RED("red", 1), BLUE("blue", 2), GREEN("green", 3);
String value;
int index;
private Color(String value, int index) {
this.value = value;
this.index = index;
}
}
@Test
public void testEnumToStringRead() {
// Should still be able to read constant name
assertThat(gson.fromJson("\"A\"", CustomToString.class)).isEqualTo(CustomToString.A);
// Should be able to read toString() value
assertThat(gson.fromJson("\"test\"", CustomToString.class)).isEqualTo(CustomToString.A);
assertThat(gson.fromJson("\"other\"", CustomToString.class)).isNull();
}
private enum CustomToString {
A;
@Override
public String toString() {
return "test";
}
}
/**
* Test that enum constant names have higher precedence than {@code toString()}
* result.
*/
@Test
public void testEnumToStringReadInterchanged() {
assertThat(gson.fromJson("\"A\"", InterchangedToString.class)).isEqualTo(InterchangedToString.A);
assertThat(gson.fromJson("\"B\"", InterchangedToString.class)).isEqualTo(InterchangedToString.B);
}
private enum InterchangedToString {
A("B"),
B("A");
private final String toString;
InterchangedToString(String toString) {
this.toString = toString;
}
@Override
public String toString() {
return toString;
}
}
}