liyafan82 commented on a change in pull request #8194: URL: https://github.com/apache/arrow/pull/8194#discussion_r489310890
########## File path: java/memory/memory-core/src/test/java/org/apache/arrow/memory/util/TestLargeMemoryUtil.java ########## @@ -0,0 +1,100 @@ +/* + * 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.arrow.memory.util; + +import java.lang.reflect.InvocationTargetException; +import java.lang.reflect.Method; +import java.net.URLClassLoader; + +import org.junit.Assert; +import org.junit.Test; + +public class TestLargeMemoryUtil { + + /** + * Get a copy of the current class loader. + * @return the newly created class loader. + */ + private ClassLoader copyClassLoader() { + ClassLoader curClassLoader = this.getClass().getClassLoader(); + if (curClassLoader instanceof URLClassLoader) { + // for Java 1.8 + return new URLClassLoader(((URLClassLoader) curClassLoader).getURLs(), null); + } + + // for Java 1.9 and Java 11. + return null; + } + + /** + * Use the checkedCastToInt method from the current classloader. + * @param classLoader the class loader from which to call the method. + * @return the return value of the method. + */ + private int checkedCastToInt(ClassLoader classLoader, long value) throws Exception { + Class<?> clazz = classLoader.loadClass("org.apache.arrow.memory.util.LargeMemoryUtil"); + Method method = clazz.getMethod("checkedCastToInt", long.class); + return (int) method.invoke(null, value); + } + + @Test + public void testEnableLargeMemoryUtilCheck() throws Exception { + String savedNewProperty = System.getProperty("arrow.enable_unsafe_memory_access"); + System.setProperty("arrow.enable_unsafe_memory_access", "false"); + try { + ClassLoader classLoader = copyClassLoader(); + if (classLoader != null) { + Assert.assertEquals(Integer.MAX_VALUE, checkedCastToInt(classLoader, Integer.MAX_VALUE)); + checkedCastToInt(classLoader, Integer.MAX_VALUE + 1L); Review comment: Can you add a case for an integer smaller than Integer.MIN_VALUE? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
