com.google.template.soy.jbcsrc.internal.MemoryClassLoaderTest.java Source code

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Here is the source code for com.google.template.soy.jbcsrc.internal.MemoryClassLoaderTest.java

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/*
 * Copyright 2015 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.template.soy.jbcsrc.internal;

import static com.google.common.truth.Truth.assertThat;
import static com.google.template.soy.jbcsrc.restricted.SoyExpression.FALSE;
import static com.google.template.soy.jbcsrc.restricted.SoyExpression.TRUE;

import com.google.common.collect.ImmutableList;
import com.google.common.io.ByteStreams;
import com.google.common.testing.GcFinalization;
import com.google.template.soy.jbcsrc.restricted.TypeInfo;
import com.google.template.soy.jbcsrc.restricted.testing.ExpressionEvaluator;
import com.google.template.soy.jbcsrc.restricted.testing.ExpressionEvaluator.BooleanInvoker;
import java.io.IOException;
import java.lang.ref.WeakReference;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.Type;
import org.objectweb.asm.tree.ClassNode;

/** Tests for {@link com.google.template.soy.jbcsrc.internal.MemoryClassLoader} */
@RunWith(JUnit4.class)
public class MemoryClassLoaderTest {

    // Our memory classloaders should be garbage collectable when all references to their types
    // disapear
    @Test
    public void testCollectable() {
        BooleanInvoker invoker = ExpressionEvaluator.createInvoker(BooleanInvoker.class, FALSE);
        assertThat(invoker.invoke()).isFalse(); // sanity, the invoker works
        MemoryClassLoader loader = (MemoryClassLoader) invoker.getClass().getClassLoader();
        WeakReference<MemoryClassLoader> loaderRef = new WeakReference<MemoryClassLoader>(loader);
        invoker = null; // unpin
        loader = null;
        GcFinalization.awaitClear(loaderRef);
    }

    @Test
    public void testAsResource() throws IOException {
        BooleanInvoker invoker = ExpressionEvaluator.createInvoker(BooleanInvoker.class, FALSE);
        byte[] classBytes = ByteStreams.toByteArray(invoker.getClass().getClassLoader()
                .getResourceAsStream(invoker.getClass().getName().replace('.', '/') + ".class"));
        ClassNode node = new ClassNode();
        new ClassReader(classBytes).accept(node, 0);
        assertThat(node.name).isEqualTo(Type.getInternalName(invoker.getClass()));
    }

    @Test
    public void testDelegation() throws Exception {
        // We want to make sure that for generated types, our classloader doesn't delegate to its parent
        // loader
        ClassData parentClass = ExpressionEvaluator.createClass(BooleanInvoker.class, FALSE);
        ClassData childClass = ExpressionEvaluator.createClass(BooleanInvoker.class, TRUE);
        // sanity check,  they have the same fully qualified class name
        assertThat(parentClass.type()).isEqualTo(childClass.type());
        TypeInfo type = childClass.type();

        MemoryClassLoader parentLoader = new MemoryClassLoader(ImmutableList.of(parentClass));
        MemoryClassLoader childLoader = new MemoryClassLoader(parentLoader, ImmutableList.of(childClass));

        BooleanInvoker fromParent = parentLoader.loadClass(type.className()).asSubclass(BooleanInvoker.class)
                .getConstructor().newInstance();
        assertThat(fromParent.invoke()).isFalse();

        BooleanInvoker fromChild = childLoader.loadClass(type.className()).asSubclass(BooleanInvoker.class)
                .getConstructor().newInstance();
        assertThat(fromChild.invoke()).isTrue();

        assertThat(fromChild.getClass()).isNotEqualTo(fromParent.getClass());
    }
}