test/hotspot/jtreg/runtime/8176717/TestInheritFD.java

8205054: Could not find "lsof" on test machine
Reviewed-by:

 import static java.io.File.createTempFile;
 import static java.lang.Long.parseLong;
 import static java.lang.System.getProperty;
 import static java.nio.file.Files.readAllBytes;
 import static java.util.Arrays.stream;
+import static java.util.Collections.emptyList;
 import static java.util.stream.Collectors.joining;
 import static java.util.stream.Collectors.toList;
 import static jdk.test.lib.process.ProcessTools.createJavaProcessBuilder;
 
 import java.io.BufferedReader;

@@ -12,10 +13,11
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.util.Collection;
+import java.util.Optional;
 import java.util.stream.Stream;
 
 /*
  * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

@@ -161,23 +163,22
         }
     }
 
     static Collection<String> outputContainingFilenames() {
         long pid = ProcessHandle.current().pid();
-        String[] command = stream(new String[][]{
+        Optional<String[]> command = stream(new String[][]{
                 {"/usr/bin/lsof", "-p"},
                 {"/usr/sbin/lsof", "-p"},
                 {"/bin/lsof", "-p"},
                 {"/sbin/lsof", "-p"},
                 {"/usr/local/bin/lsof", "-p"},
                 {"/usr/bin/pfiles", "-F"}}) // Solaris
             .filter(args -> new File(args[0]).exists())
-            .findFirst()
-            .orElseThrow(() -> new RuntimeException("could not find lsof-like command"));
+            .findFirst();
 
-        System.out.println("using command: " + command[0] + " " + command[1]);
-        return run(command[0], command[1], "" + pid).collect(toList());
+        System.out.println("using command: " + command.map((c) -> c[0] + " " + c[1]).orElse("<not found>"));
+        return command.map(c -> run(c[0], c[1], "" + pid).collect(toList())).orElse(emptyList()); // if command can not be found return list without log file (some machines does not have "lsof" in the expected place)
     }
 
     static boolean findOpenLogFile(Collection<String> fileNames) {
         return fileNames.stream()
             .filter(fileName -> fileName.contains(LOG_SUFFIX))