flink-core/src/test/java/org/apache/flink/api/common/typeinfo/TypeHintTest.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.flink.api.common.typeinfo;

import org.apache.flink.api.java.tuple.Tuple3;
import org.apache.flink.api.java.typeutils.TupleTypeInfo;
import org.apache.flink.util.FlinkRuntimeException;

import org.junit.Test;

import java.util.List;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

/**
 * Tests for the {@link TypeHint}.
 */
public class TypeHintTest {

	@Test
	public void testTypeInfoDirect() {

		// simple (non-generic case)
		TypeHint<String> stringInfo1 = new TypeHint<String>(){};
		TypeHint<String> stringInfo2 = new TypeHint<String>(){};

		assertEquals(BasicTypeInfo.STRING_TYPE_INFO, stringInfo1.getTypeInfo());

		assertTrue(stringInfo1.hashCode() == stringInfo2.hashCode());
		assertTrue(stringInfo1.equals(stringInfo2));
		assertTrue(stringInfo1.toString().equals(stringInfo2.toString()));

		// generic case
		TypeHint<Tuple3<String, Double, Boolean>> generic = new TypeHint<Tuple3<String, Double, Boolean>>(){};

		TypeInformation<Tuple3<String, Double, Boolean>> tupleInfo =
				new TupleTypeInfo<>(BasicTypeInfo.STRING_TYPE_INFO, BasicTypeInfo.DOUBLE_TYPE_INFO, BasicTypeInfo.BOOLEAN_TYPE_INFO);

		assertEquals(tupleInfo, generic.getTypeInfo());
	}

	@Test
	public <T> void testWithGenericParameter() {
		try {
			new TypeHint<T>(){};
			fail();
		}
		catch (FlinkRuntimeException ignored) {}

		// this works, because "List" goes to the GenericType (blackbox) which does
		// not care about generic parametrization
		new TypeHint<List<T>>(){};
	}
}