src/test/java/org/apache/commons/collections4/TrieUtilsTest.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.commons.collections4;

import static org.junit.Assert.*;

import org.apache.commons.collections4.trie.PatriciaTrie;
import org.apache.commons.collections4.trie.UnmodifiableTrie;
import org.junit.Test;

/**
 * Tests for TrieUtils factory methods.
 *
 */
public class TrieUtilsTest {

    //----------------------------------------------------------------------

    @Test
    public void testUnmodifiableTrie() {
        final Trie<String, Object> trie = TrieUtils.unmodifiableTrie(new PatriciaTrie<>());
        assertTrue("Returned object should be an UnmodifiableTrie.",
            trie instanceof UnmodifiableTrie);
        try {
            TrieUtils.unmodifiableTrie(null);
            fail("Expecting NullPointerException for null trie.");
        } catch (final NullPointerException ex) {
            // expected
        }

        assertSame("UnmodifiableTrie shall not be decorated", trie, TrieUtils.unmodifiableTrie(trie));
    }

}