diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/util/ProcfsBasedProcessTree.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/util/ProcfsBasedProcessTree.java index a08b90e..48fb1f8 100644 --- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/util/ProcfsBasedProcessTree.java +++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/util/ProcfsBasedProcessTree.java @@ -484,6 +484,10 @@ private static String getValidPID(String pid) { String[] processDirs = (new File(procfsDir)).list(); List processList = new ArrayList(); + if (processDirs == null) { + return processList; + } + for (String dir : processDirs) { Matcher m = numberPattern.matcher(dir); if (!m.matches()) continue;