mattyb149 commented on a change in pull request #5062: URL: https://github.com/apache/nifi/pull/5062#discussion_r628281726
########## File path: minifi/minifi-bootstrap/src/main/java/org/apache/nifi/minifi/bootstrap/util/OSUtils.java ########## @@ -0,0 +1,152 @@ +/* + * 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.nifi.minifi.bootstrap.util; + +import com.sun.jna.Pointer; +import com.sun.jna.platform.win32.Kernel32; +import com.sun.jna.platform.win32.WinNT; +import org.slf4j.Logger; + +import java.lang.reflect.Field; +import java.lang.reflect.InvocationTargetException; +import java.lang.reflect.Method; +import java.util.regex.Matcher; +import java.util.regex.Pattern; + +/** + * OS specific utilities with generic method interfaces + */ +public final class OSUtils { + /** + * @param process MiNiFi Process Reference + * @param logger Logger Reference for Debug + * @return Returns pid or null in-case pid could not be determined + * This method takes {@link Process} and {@link Logger} and returns + * the platform specific ProcessId for Unix like systems or Handle for Win32 Systems, a.k.a <b>pid</b> + * In-case it fails to determine the pid, it will return Null. + * Purpose for the Logger is to log any interaction for debugging. + */ + public static Long getProcessId(final Process process, final Logger logger) { + /* + * NIFI-5175: NiFi built with Java 1.8 and running on Java 9. Reflectively invoke Process.pid() on + * the given process instance to get the PID of this Java process. Reflection is required in this scenario + * due to NiFi being compiled on Java 1.8, which does not have the Process API improvements available in + * Java 9. + * + * Otherwise, if NiFi is running on Java 1.8, attempt to get PID using capabilities available on Java 1.8. + * + * TODO: When minimum Java version updated to Java 9+, this class should be removed with the addition + * of the pid method to the Process API. + */ + Long pid = null; + try { + // Get Process.pid() interface method to avoid illegal reflective access + final Method pidMethod = Process.class.getDeclaredMethod("pid"); + final Object pidNumber = pidMethod.invoke(process); + if (pidNumber instanceof Long) { + pid = (Long) pidNumber; + } + } catch (final NoSuchMethodException | IllegalAccessException | InvocationTargetException e) { + final String processClassName = process.getClass().getName(); + if (processClassName.equals("java.lang.UNIXProcess")) { + pid = getUnixPid(process, logger); + } else if (processClassName.equals("java.lang.Win32Process") + || processClassName.equals("java.lang.ProcessImpl")) { + pid = getWindowsProcessId(process, logger); + } else { + logger.debug("Failed to determine Process ID from [{}]: {}", processClassName, e.getMessage()); + } + } + + return pid; + } + + /** + * Returns the major version parsed from the provided Java version string (e.g. {@code "1.8.0.231"} -> {@code 8}). + * + * @param version the Java version string + * @return the major version as an int + */ + public static int parseJavaVersion(final String version) { + String majorVersion; + if (version.startsWith("1.")) { + majorVersion = version.substring(2, 3); + } else { + Pattern majorVersion9PlusPattern = Pattern.compile("(\\d+).*"); + Matcher m = majorVersion9PlusPattern.matcher(version); + if (m.find()) { + majorVersion = m.group(1); + } else { + throw new IllegalArgumentException("Could not detect major version of " + version); + } + } + return Integer.parseInt(majorVersion); + } Review comment: I waffled on whether to make a new module, but I think you're right. I can create a "nifi-bootstrap-utils" module and just include this for now (and share it among nifi-bootstrap and minifi-bootstrap). That way the code is in one place to maintain, but doesn't add any footprint as it would if it were in nifi-utils. -- 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]
