| /* |
| * 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.collect; |
| |
| import com.google.common.base.Function; |
| import com.google.common.collect.Interners.InternerImpl; |
| import com.google.common.collect.MapMakerInternalMap.Strength; |
| import com.google.common.testing.GcFinalization; |
| import com.google.common.testing.NullPointerTester; |
| import java.lang.ref.WeakReference; |
| import junit.framework.TestCase; |
| |
| /** |
| * Unit test for {@link Interners}. |
| * |
| * @author Kevin Bourrillion |
| */ |
| public class InternersTest extends TestCase { |
| |
| public void testStrong_simplistic() { |
| String canonical = "a"; |
| String not = new String("a"); |
| |
| Interner<String> pool = Interners.newStrongInterner(); |
| assertSame(canonical, pool.intern(canonical)); |
| assertSame(canonical, pool.intern(not)); |
| } |
| |
| public void testStrong_null() { |
| Interner<String> pool = Interners.newStrongInterner(); |
| try { |
| pool.intern(null); |
| fail(); |
| } catch (NullPointerException ok) { |
| } |
| } |
| |
| public void testStrong_builder() { |
| int concurrencyLevel = 42; |
| Interner<Object> interner = |
| Interners.newBuilder().strong().concurrencyLevel(concurrencyLevel).build(); |
| InternerImpl<Object> internerImpl = (InternerImpl<Object>) interner; |
| assertEquals(Strength.STRONG, internerImpl.map.keyStrength()); |
| } |
| |
| public void testWeak_simplistic() { |
| String canonical = "a"; |
| String not = new String("a"); |
| |
| Interner<String> pool = Interners.newWeakInterner(); |
| assertSame(canonical, pool.intern(canonical)); |
| assertSame(canonical, pool.intern(not)); |
| } |
| |
| public void testWeak_null() { |
| Interner<String> pool = Interners.newWeakInterner(); |
| try { |
| pool.intern(null); |
| fail(); |
| } catch (NullPointerException ok) { |
| } |
| } |
| |
| public void testWeak_builder() { |
| int concurrencyLevel = 42; |
| Interner<Object> interner = |
| Interners.newBuilder().weak().concurrencyLevel(concurrencyLevel).build(); |
| InternerImpl<Object> internerImpl = (InternerImpl<Object>) interner; |
| assertEquals(Strength.WEAK, internerImpl.map.keyStrength()); |
| assertEquals(concurrencyLevel, internerImpl.map.concurrencyLevel); |
| } |
| |
| public void testWeak_afterGC() throws InterruptedException { |
| Integer canonical = new Integer(5); |
| Integer not = new Integer(5); |
| |
| Interner<Integer> pool = Interners.newWeakInterner(); |
| assertSame(canonical, pool.intern(canonical)); |
| |
| WeakReference<Integer> signal = new WeakReference<>(canonical); |
| canonical = null; // Hint to the JIT that canonical is unreachable |
| |
| GcFinalization.awaitClear(signal); |
| assertSame(not, pool.intern(not)); |
| } |
| |
| public void testAsFunction_simplistic() { |
| String canonical = "a"; |
| String not = new String("a"); |
| |
| Function<String, String> internerFunction = |
| Interners.asFunction(Interners.<String>newStrongInterner()); |
| |
| assertSame(canonical, internerFunction.apply(canonical)); |
| assertSame(canonical, internerFunction.apply(not)); |
| } |
| |
| public void testNullPointerExceptions() { |
| new NullPointerTester().testAllPublicStaticMethods(Interners.class); |
| } |
| |
| public void testConcurrencyLevel_Zero() { |
| Interners.InternerBuilder builder = Interners.newBuilder(); |
| try { |
| builder.concurrencyLevel(0); |
| fail(); |
| } catch (IllegalArgumentException expected) { |
| } |
| } |
| |
| public void testConcurrencyLevel_Negative() { |
| Interners.InternerBuilder builder = Interners.newBuilder(); |
| try { |
| builder.concurrencyLevel(-42); |
| fail(); |
| } catch (IllegalArgumentException expected) { |
| } |
| } |
| } |