Java example source code file (TypeTokenTest.java)

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Java - Java tags/keywords

assignability, integer, iterable, list, n11, number, parameterizedtype, reflection, string, suppresswarnings, typecapture, typetoken, util

The TypeTokenTest.java Java example source code

/*
 * Copyright (C) 2007 The Guava Authors
 *
 * 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.common.reflect;

import static com.google.common.truth.Truth.assertThat;

import com.google.common.base.Function;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Maps;
import com.google.common.primitives.Primitives;
import com.google.common.testing.EqualsTester;
import com.google.common.testing.NullPointerTester;
import com.google.common.testing.SerializableTester;
import com.google.common.truth.IterableSubject;
import com.google.errorprone.annotations.CanIgnoreReturnValue;

import junit.framework.TestCase;

import java.io.Serializable;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.GenericArrayType;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.lang.reflect.WildcardType;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;

/**
 * Test cases for {@link TypeToken}.
 *
 * @author Sven Mawson
 * @author Ben Yu
 */
@AndroidIncompatible // lots of failures, possibly some related to bad equals() implementations?
public class TypeTokenTest extends TestCase {

  private abstract static class StringList implements List<String> {}

  private abstract static class IntegerList implements List<Integer> {}

  public void testValueEqualityNotInstanceEquality() {
    TypeToken<List a = new TypeToken>() {};
    TypeToken<List b = new TypeToken>() {};
    assertEquals(a, b);
  }

  public <T> void testVariableTypeTokenNotAllowed() {
    try {
      new TypeToken<T>() {};
      fail();
    } catch (IllegalStateException expected) {}
  }

  public void testRawTypeIsCorrect() {
    TypeToken<List token = new TypeToken>() {};
    assertEquals(List.class, token.getRawType());
  }

  public void testTypeIsCorrect() {
    TypeToken<List token = new TypeToken>() {};
    assertEquals(StringList.class.getGenericInterfaces()[0], token.getType());
  }

  @SuppressWarnings("rawtypes") // Trying to test TypeToken.of(List.class)
  public void testGetClass() {
    TypeToken<List> token = TypeToken.of(List.class);
    assertEquals(new TypeToken<List>() {}, token);
  }

  public void testGetType() {
    TypeToken<?> t = TypeToken.of(StringList.class.getGenericInterfaces()[0]);
    assertEquals(new TypeToken<List() {}, t);
  }

  public void testNonStaticLocalClass() {
    class Local<T> {}
    TypeToken<Local type = new TypeToken>() {};
    assertEquals(Types.newParameterizedType(Local.class, String.class),
        type.getType());
    assertEquals(new Local<String>() {}.getClass().getGenericSuperclass(), type.getType());
  }

  public void testStaticLocalClass() {
    doTestStaticLocalClass();
  }

  private static void doTestStaticLocalClass() {
    class Local<T> {}
    TypeToken<Local type = new TypeToken>() {};
    assertEquals(Types.newParameterizedType(Local.class, String.class),
        type.getType());
    assertEquals(new Local<String>() {}.getClass().getGenericSuperclass(), type.getType());
  }

  public void testGenericArrayType() {
    TypeToken<List token = new TypeToken[]>() {};
    assertEquals(List[].class, token.getRawType());
    assertThat(token.getType()).isInstanceOf(GenericArrayType.class);
  }

  public void testMultiDimensionalGenericArrayType() {
    TypeToken<List token = new TypeToken[][][]>() {};
    assertEquals(List[][][].class, token.getRawType());
    assertThat(token.getType()).isInstanceOf(GenericArrayType.class);
  }

  public <T> void testGenericVariableTypeArrays() {
    assertEquals("T[]", new TypeToken<T[]>() {}.toString());
  }

  public void testResolveType() throws Exception {
    Method getFromList = List.class.getMethod("get", int.class);
    TypeToken<?> returnType = new TypeToken>() {}
        .resolveType(getFromList.getGenericReturnType());
    assertEquals(String.class, returnType.getType());
  }

  public <F extends Enum & Iterable>
  void testResolveType_fromTypeVariable() {
    TypeToken<?> f = TypeToken.of(new TypeCapture() {}.capture());
    assertEquals(String.class,
        f.resolveType(Function.class.getTypeParameters()[0]).getType());
    assertEquals(Integer.class,
        f.resolveType(Function.class.getTypeParameters()[1]).getType());
    assertEquals(Long.class,
        f.resolveType(Iterable.class.getTypeParameters()[0]).getType());
  }

  public <E extends Comparable & Iterable>
  void testResolveType_fromTypeVariable_onlyDirectBoundsAreUsed() {
    TypeToken<?> e = TypeToken.of(new TypeCapture() {}.capture());
    assertEquals(Integer.class,
        e.resolveType(Iterable.class.getTypeParameters()[0]).getType());
  }

  public void testResolveType_fromWildcard() {
    ParameterizedType withWildcardType = (ParameterizedType)
        new TypeCapture<Comparable>() {}.capture();
    TypeToken<?> wildcardType = TypeToken.of(withWildcardType.getActualTypeArguments()[0]);
    assertEquals(String.class,
        wildcardType.resolveType(Iterable.class.getTypeParameters()[0]).getType());
  }

  public void testGetTypes_noSuperclass() {
    TypeToken<Object>.TypeSet types = new TypeToken