[ https://issues.apache.org/jira/browse/HADOOP-13191?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
John Zhuge resolved HADOOP-13191. --------------------------------- Resolution: Duplicate Thanks [~boky01], it is a dup of HADOOP-7352. One idea is to add {{@NotNull}} to {{FileSystem#listStatus}}: {code} @NotNull public abstract FileStatus[] listStatus(Path f) throws IOException; {code} Then run IntelliJ - Analyze - "Run Inspection by Name ..." - "@NotNull/@Nullible problems" (multiple times if necessary) in order to: * Propagate {{@NotNull}} to subclasses' {{listStatus}} method * Detect any implementation of {{listStatus}} that may return {{null}} > FileSystem#listStatus should not return null > -------------------------------------------- > > Key: HADOOP-13191 > URL: https://issues.apache.org/jira/browse/HADOOP-13191 > Project: Hadoop Common > Issue Type: Bug > Components: fs > Affects Versions: 2.6.0 > Reporter: John Zhuge > Assignee: John Zhuge > Priority: Minor > > This came out of discussion in HADOOP-12718. The {{FileSystem#listStatus}} > contract does not indicate {{null}} is a valid return and some callers do not > test {{null}} before use: > AbstractContractGetFileStatusTest#testListStatusEmptyDirectory: > {code} > assertEquals("ls on an empty directory not of length 0", 0, > fs.listStatus(subfolder).length); > {code} > ChecksumFileSystem#copyToLocalFile: > {code} > FileStatus[] srcs = listStatus(src); > for (FileStatus srcFile : srcs) { > {code} > SimpleCopyLIsting#getFileStatus: > {code} > FileStatus[] fileStatuses = fileSystem.listStatus(path); > if (excludeList != null && excludeList.size() > 0) { > ArrayList<FileStatus> fileStatusList = new ArrayList<>(); > for(FileStatus status : fileStatuses) { > {code} > IMHO, there is no good reason for {{listStatus}} to return {{null}}. It > should return empty list instead. > To enforce the contract that null is an invalid return, update javadoc and > consider Intellij IDEA's @Nullable and @NotNull annotations. > So far, I am only aware of the following functions that can return null: > * RawLocalFileSystem#listStatus -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-issues-h...@hadoop.apache.org