HADOOP-7202. Improve shell Command base class. Contributed by Daryn Sharp
git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1086446 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Tsz-wo Sze
parent
1c0d271329
commit
50b1f9fc73
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@ -84,6 +84,8 @@ Trunk (unreleased changes)
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HADOOP-7180. Better support on CommandFormat on the API and exceptions.
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(Daryn Sharp via szetszwo)
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HADOOP-7202. Improve shell Command base class. (Daryn Sharp via szetszwo)
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OPTIMIZATIONS
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HADOOP-6949. Reduce RPC packet size of primitive arrays using
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@ -370,7 +370,7 @@ public class FsShell extends Configured implements Tool {
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private class TextRecordInputStream extends InputStream {
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SequenceFile.Reader r;
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WritableComparable key;
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WritableComparable<?> key;
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Writable val;
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DataInputBuffer inbuf;
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@ -1691,8 +1691,6 @@ public class FsShell extends Configured implements Tool {
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delete(argv[i], true, rmSkipTrash);
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} else if ("-df".equals(cmd)) {
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df(argv[i]);
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} else if (Count.matches(cmd)) {
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new Count(argv, i, getConf()).runAll();
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} else if ("-ls".equals(cmd)) {
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exitCode = ls(argv[i], false);
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} else if ("-lsr".equals(cmd)) {
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@ -1759,7 +1757,7 @@ public class FsShell extends Configured implements Tool {
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} else if ("-df".equals(cmd) ) {
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System.err.println("Usage: java FsShell" +
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" [" + cmd + " [<path>]]");
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} else if (Count.matches(cmd)) {
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} else if ("-count".equals(cmd)) {
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System.err.println(prefix + " [" + Count.USAGE + "]");
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} else if ("-rm".equals(cmd) || "-rmr".equals(cmd)) {
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System.err.println("Usage: java FsShell [" + cmd +
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@ -1948,8 +1946,13 @@ public class FsShell extends Configured implements Tool {
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du(argv, i);
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} else if ("-dus".equals(cmd)) {
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dus(argv, i);
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} else if (Count.matches(cmd)) {
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exitCode = new Count(argv, i, getConf()).runAll();
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} else if ("-count".equals(cmd)) {
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// TODO: next two lines are a temporary crutch until this entire
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// block is overhauled
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LinkedList<String> args = new LinkedList<String>(Arrays.asList(argv));
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args.removeFirst();
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Count runner = ReflectionUtils.newInstance(Count.class, getConf());
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exitCode = runner.run(cmd, args);
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} else if ("-mkdir".equals(cmd)) {
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exitCode = doall(cmd, argv, i);
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} else if ("-touchz".equals(cmd)) {
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@ -17,27 +17,53 @@
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*/
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package org.apache.hadoop.fs.shell;
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import java.io.*;
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import java.io.FileNotFoundException;
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import java.io.IOException;
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import java.io.PrintStream;
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import java.util.ArrayList;
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import java.util.LinkedList;
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import java.util.List;
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import org.apache.commons.logging.Log;
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import org.apache.commons.logging.LogFactory;
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import org.apache.hadoop.classification.InterfaceAudience;
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import org.apache.hadoop.classification.InterfaceStability;
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import org.apache.hadoop.conf.Configuration;
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import org.apache.hadoop.conf.Configured;
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import org.apache.hadoop.fs.FileStatus;
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import org.apache.hadoop.fs.FileSystem;
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import org.apache.hadoop.fs.Path;
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import org.apache.hadoop.ipc.RemoteException;
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import org.apache.hadoop.util.StringUtils;
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/**
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* An abstract class for the execution of a file system command
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*/
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@InterfaceAudience.Private
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@InterfaceStability.Evolving
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abstract public class Command extends Configured {
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protected String[] args;
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protected String cmdName;
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protected int exitCode = 0;
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protected int numErrors = 0;
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protected boolean recursive = false;
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protected ArrayList<Exception> exceptions = new ArrayList<Exception>();
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private static final Log LOG = LogFactory.getLog(Command.class);
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/** allows stdout to be captured if necessary */
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public PrintStream out = System.out;
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/** allows stderr to be captured if necessary */
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public PrintStream err = System.err;
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protected Command() {}
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/** Constructor */
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protected Command(Configuration conf) {
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super(conf);
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}
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/** Return the command's name excluding the leading character - */
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/** @return the command's name excluding the leading character - */
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abstract public String getCommandName();
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/**
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@ -57,30 +83,273 @@ abstract public class Command extends Configured {
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int exitCode = 0;
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for (String src : args) {
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try {
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Path srcPath = new Path(src);
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FileSystem fs = srcPath.getFileSystem(getConf());
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FileStatus[] statuses = fs.globStatus(srcPath);
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if (statuses == null) {
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System.err.println("Can not find listing for " + src);
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exitCode = -1;
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} else {
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for(FileStatus s : statuses) {
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run(s.getPath());
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}
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List<PathData> srcs = expandGlob(src);
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for(PathData s : srcs) {
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run(s.path);
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}
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} catch (RemoteException re) {
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exitCode = -1;
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String content = re.getLocalizedMessage();
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int eol = content.indexOf('\n');
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if (eol>=0) {
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content = content.substring(0, eol);
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}
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System.err.println(getCommandName() + ": " + content);
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} catch (IOException e) {
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exitCode = -1;
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System.err.println(getCommandName() + ": " + e.getLocalizedMessage());
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displayError(e);
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}
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}
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return exitCode;
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}
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/**
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* Invokes the command handler. The default behavior is to process options,
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* expand arguments, and then process each argument.
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* <pre>
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* run
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* \-> {@link #processOptions(LinkedList)}
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* \-> {@link #expandArguments(LinkedList)} -> {@link #expandArgument(String)}*
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* \-> {@link #processArguments(LinkedList)}
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* \-> {@link #processArgument(PathData)}*
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* \-> {@link #processPathArgument(PathData)}
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* \-> {@link #processPaths(PathData, PathData...)}
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* \-> {@link #processPath(PathData)}*
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* \-> {@link #processNonexistentPathArgument(PathData)}
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* </pre>
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* Most commands will chose to implement just
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* {@link #processOptions(LinkedList)} and {@link #processPath(PathData)}
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*
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* @param cmd the command's name
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* @param args the list of command line arguments
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* @return the exit code for the command
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* @throws IllegalArgumentException if called with invalid arguments
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*/
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public int run(String cmd, LinkedList<String> args) {
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cmdName = cmd;
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try {
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processOptions(args);
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processArguments(expandArguments(args));
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} catch (IOException e) {
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displayError(e);
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}
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return (numErrors == 0) ? exitCode : 1;
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}
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/**
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* Must be implemented by commands to process the command line flags and
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* check the bounds of the remaining arguments. If an
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* IllegalArgumentException is thrown, the FsShell object will print the
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* short usage of the command.
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* @param args the command line arguments
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* @throws IOException
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*/
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protected void processOptions(LinkedList<String> args) throws IOException {}
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/**
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* Expands a list of arguments into {@link PathData} objects. The default
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* behavior is to call {@link #expandArgument(String)} on each element
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* which by default globs the argument. The loop catches IOExceptions,
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* increments the error count, and displays the exception.
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* @param args strings to expand into {@link PathData} objects
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* @return list of all {@link PathData} objects the arguments
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* @throws IOException if anything goes wrong...
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*/
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protected LinkedList<PathData> expandArguments(LinkedList<String> args)
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throws IOException {
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LinkedList<PathData> expandedArgs = new LinkedList<PathData>();
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for (String arg : args) {
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try {
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expandedArgs.addAll(expandArgument(arg));
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} catch (IOException e) { // other exceptions are probably nasty
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displayError(e);
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}
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}
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return expandedArgs;
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}
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/**
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* Expand the given argument into a list of {@link PathData} objects.
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* The default behavior is to expand globs. Commands may override to
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* perform other expansions on an argument.
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* @param arg string pattern to expand
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* @return list of {@link PathData} objects
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* @throws IOException if anything goes wrong...
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*/
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protected List<PathData> expandArgument(String arg) throws IOException {
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return expandGlob(arg);
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}
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/**
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* Processes the command's list of expanded arguments.
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* {@link #processArgument(PathData)} will be invoked with each item
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* in the list. The loop catches IOExceptions, increments the error
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* count, and displays the exception.
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* @param args a list of {@link PathData} to process
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* @throws IOException if anything goes wrong...
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*/
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protected void processArguments(LinkedList<PathData> args)
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throws IOException {
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for (PathData arg : args) {
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try {
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processArgument(arg);
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} catch (IOException e) {
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displayError(e);
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}
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}
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}
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/**
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* Processes a {@link PathData} item, calling
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* {@link #processPathArgument(PathData)} or
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* {@link #processNonexistentPathArgument(PathData)} on each item.
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* @param arg {@link PathData} item to process
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* @throws IOException if anything goes wrong...
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*/
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protected void processArgument(PathData item) throws IOException {
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if (item.exists) {
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processPathArgument(item);
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} else {
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processNonexistentPathArgument(item);
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}
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}
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/**
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* This is the last chance to modify an argument before going into the
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* (possibly) recursive {@link #processPaths(PathData, PathData...)}
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* -> {@link #processPath(PathData)} loop. Ex. ls and du use this to
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* expand out directories.
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* @param item a {@link PathData} representing a path which exists
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* @throws IOException if anything goes wrong...
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*/
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protected void processPathArgument(PathData item) throws IOException {
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// null indicates that the call is not via recursion, ie. there is
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// no parent directory that was expanded
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processPaths(null, item);
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}
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/**
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* Provides a hook for handling paths that don't exist. By default it
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* will throw an exception. Primarily overriden by commands that create
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* paths such as mkdir or touch.
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* @param item the {@link PathData} that doesn't exist
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* @throws FileNotFoundException if arg is a path and it doesn't exist
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* @throws IOException if anything else goes wrong...
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*/
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protected void processNonexistentPathArgument(PathData item)
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throws IOException {
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throw new FileNotFoundException(item + ": No such file or directory");
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}
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/**
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* Iterates over the given expanded paths and invokes
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* {@link #processPath(PathData)} on each element. If "recursive" is true,
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* will do a post-visit DFS on directories.
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* @param parent if called via a recurse, will be the parent dir, else null
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* @param items a list of {@link PathData} objects to process
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* @throws IOException if anything goes wrong...
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*/
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protected void processPaths(PathData parent, PathData ... items)
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throws IOException {
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// TODO: this really should be iterative
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for (PathData item : items) {
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try {
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processPath(item);
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if (recursive && item.stat.isDirectory()) {
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recursePath(item);
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}
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} catch (IOException e) {
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displayError(e);
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}
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}
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}
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/**
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* Hook for commands to implement an operation to be applied on each
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* path for the command. Note implementation of this method is optional
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* if earlier methods in the chain handle the operation.
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* @param item a {@link PathData} object
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* @throws RuntimeException if invoked but not implemented
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* @throws IOException if anything else goes wrong in the user-implementation
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*/
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protected void processPath(PathData item) throws IOException {
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throw new RuntimeException("processPath() is not implemented");
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}
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/**
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* Gets the directory listing for a path and invokes
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* {@link #processPaths(PathData, PathData...)}
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* @param item {@link PathData} for directory to recurse into
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* @throws IOException if anything goes wrong...
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*/
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protected void recursePath(PathData item) throws IOException {
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processPaths(item, item.getDirectoryContents());
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}
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/**
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* Expand the given path as a glob pattern. Non-existent paths do not
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* throw an exception because creation commands like touch and mkdir need
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* to create them. The "stat" field will be null if the path does not
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* exist.
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* @param pattern the glob to expand
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* @return list of {@link PathData} objects
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* @throws FileNotFoundException the path is a glob with no matches
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* @throws IOException anything else goes wrong...
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*/
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protected List<PathData> expandGlob(String pattern) throws IOException {
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Path path = new Path(pattern);
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FileSystem fs = path.getFileSystem(getConf());
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FileStatus[] stats = fs.globStatus(path);
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if (stats != null && stats.length == 0) { // glob failed to match
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throw new FileNotFoundException(path + ": No such file or directory");
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}
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List<PathData> items = new LinkedList<PathData>();
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if (stats == null) { // not a glob & file not found, so null stat block
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items.add(new PathData(fs, path, null));
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} else {
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// convert all the stats to PathData objs
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for (FileStatus stat : stats) {
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items.add(new PathData(fs, stat));
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}
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}
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return items;
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}
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/**
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* Display an exception prefaced with the command name. Also increments
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* the error count for the command which will result in a non-zero exit
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* code.
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* @param e exception to display
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*/
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public void displayError(Exception e) {
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// build up a list of exceptions that occurred
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exceptions.add(e);
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String errorMessage = e.getLocalizedMessage();
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if (errorMessage == null) {
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// this is an unexpected condition, so dump the whole exception since
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// it's probably a nasty internal error where the backtrace would be
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// useful
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errorMessage = StringUtils.stringifyException(e);
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LOG.debug(errorMessage);
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} else {
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errorMessage = errorMessage.split("\n", 2)[0];
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}
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displayError(errorMessage);
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}
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/**
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* Display an error string prefaced with the command name. Also increments
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* the error count for the command which will result in a non-zero exit
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* code.
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* @param message error message to display
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*/
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public void displayError(String message) {
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numErrors++;
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displayWarning(message);
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}
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/**
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* Display an warning string prefaced with the command name.
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* @param message warning message to display
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*/
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public void displayWarning(String message) {
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String cmd = cmdName.startsWith("-") ? cmdName.substring(1) : cmdName;
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err.println(cmd + ": " + message);
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}
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}
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@ -17,19 +17,22 @@
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*/
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package org.apache.hadoop.fs.shell;
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import java.io.*;
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import java.util.List;
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import java.io.IOException;
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import java.util.LinkedList;
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import org.apache.hadoop.conf.Configuration;
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import org.apache.hadoop.fs.FileSystem;
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import org.apache.hadoop.fs.Path;
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import org.apache.hadoop.classification.InterfaceAudience;
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import org.apache.hadoop.classification.InterfaceStability;
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import org.apache.hadoop.fs.ContentSummary;
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/**
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* Count the number of directories, files, bytes, quota, and remaining quota.
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*/
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public class Count extends Command {
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@InterfaceAudience.Private
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@InterfaceStability.Evolving
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public class Count extends FsCommand {
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public static final String NAME = "count";
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public static final String USAGE = "-" + NAME + "[-q] <path>";
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public static final String USAGE = "-" + NAME + " [-q] <path> ...";
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public static final String DESCRIPTION = CommandUtils.formatDescription(USAGE,
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"Count the number of directories, files and bytes under the paths",
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"that match the specified file pattern. The output columns are:",
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@ -37,41 +40,21 @@ public class Count extends Command {
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"QUOTA REMAINING_QUATA SPACE_QUOTA REMAINING_SPACE_QUOTA ",
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" DIR_COUNT FILE_COUNT CONTENT_SIZE FILE_NAME");
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private boolean qOption;
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private boolean showQuotas;
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/** Constructor
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*
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* @param cmd the count command
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* @param pos the starting index of the arguments
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*/
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public Count(String[] cmd, int pos, Configuration conf) {
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super(conf);
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CommandFormat c = new CommandFormat(NAME, 1, Integer.MAX_VALUE, "q");
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List<String> parameters = c.parse(cmd, pos);
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this.args = parameters.toArray(new String[parameters.size()]);
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if (this.args.length == 0) { // default path is the current working directory
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this.args = new String[] {"."};
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@Override
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protected void processOptions(LinkedList<String> args) {
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CommandFormat cf = new CommandFormat(NAME, 1, Integer.MAX_VALUE, "q");
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cf.parse(args);
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if (args.size() == 0) { // default path is the current working directory
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args.add(".");
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}
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this.qOption = c.getOpt("q") ? true: false;
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}
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/** Check if a command is the count command
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*
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* @param cmd A string representation of a command starting with "-"
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* @return true if this is a count command; false otherwise
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*/
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public static boolean matches(String cmd) {
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return ("-" + NAME).equals(cmd);
|
||||
showQuotas = cf.getOpt("q");
|
||||
}
|
||||
|
||||
@Override
|
||||
public String getCommandName() {
|
||||
return NAME;
|
||||
}
|
||||
|
||||
@Override
|
||||
protected void run(Path path) throws IOException {
|
||||
FileSystem fs = path.getFileSystem(getConf());
|
||||
System.out.println(fs.getContentSummary(path).toString(qOption) + path);
|
||||
protected void processPath(PathData src) throws IOException {
|
||||
ContentSummary summary = src.fs.getContentSummary(src.path);
|
||||
out.println(summary.toString(showQuotas) + src.path);
|
||||
}
|
||||
}
|
||||
|
|
|
|||
|
|
@ -0,0 +1,46 @@
|
|||
/**
|
||||
* 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.hadoop.fs.shell;
|
||||
|
||||
import java.io.IOException;
|
||||
|
||||
import org.apache.hadoop.classification.InterfaceAudience;
|
||||
import org.apache.hadoop.classification.InterfaceStability;
|
||||
import org.apache.hadoop.fs.Path;
|
||||
|
||||
/**
|
||||
* Base class for all "hadoop fs" commands
|
||||
*/
|
||||
|
||||
@InterfaceAudience.Private
|
||||
@InterfaceStability.Evolving
|
||||
|
||||
// this class may not look useful now, but it's a placeholder for future
|
||||
// functionality to act as a registry for fs commands. currently it's being
|
||||
// used to implement unnecessary abstract methods in the base class
|
||||
|
||||
abstract public class FsCommand extends Command {
|
||||
public String getCommandName() {
|
||||
return cmdName;
|
||||
}
|
||||
|
||||
protected void run(Path path) throws IOException {
|
||||
throw new RuntimeException("not supposed to get here");
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,123 @@
|
|||
/**
|
||||
* 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.hadoop.fs.shell;
|
||||
|
||||
import java.io.FileNotFoundException;
|
||||
import java.io.IOException;
|
||||
|
||||
import org.apache.hadoop.classification.InterfaceAudience;
|
||||
import org.apache.hadoop.classification.InterfaceStability;
|
||||
import org.apache.hadoop.fs.FileStatus;
|
||||
import org.apache.hadoop.fs.FileSystem;
|
||||
import org.apache.hadoop.fs.Path;
|
||||
|
||||
/**
|
||||
* Encapsulates a Path (path), its FileStatus (stat), and its FileSystem (fs).
|
||||
* The stat field will be null if the path does not exist.
|
||||
*/
|
||||
@InterfaceAudience.Private
|
||||
@InterfaceStability.Evolving
|
||||
|
||||
public class PathData {
|
||||
public final Path path;
|
||||
public FileStatus stat;
|
||||
public final FileSystem fs;
|
||||
public boolean exists;
|
||||
|
||||
/**
|
||||
* Creates an object to wrap the given parameters as fields.
|
||||
* @param theFs the FileSystem
|
||||
* @param thePath a Path
|
||||
* @param theStat the FileStatus (may be null if the path doesn't exist)
|
||||
*/
|
||||
public PathData(FileSystem theFs, Path thePath, FileStatus theStat) {
|
||||
path = thePath;
|
||||
stat = theStat;
|
||||
fs = theFs;
|
||||
exists = (stat != null);
|
||||
}
|
||||
|
||||
/**
|
||||
* Convenience ctor that looks up the file status for a path. If the path
|
||||
* doesn't exist, then the status will be null
|
||||
* @param fs the FileSystem for the path
|
||||
* @param path the pathname to lookup
|
||||
* @throws IOException
|
||||
*/
|
||||
public PathData(FileSystem fs, Path path) throws IOException {
|
||||
this(fs, path, getStat(fs, path));
|
||||
}
|
||||
|
||||
// need a static method for the ctor above
|
||||
private static FileStatus getStat(FileSystem fs, Path path)
|
||||
throws IOException {
|
||||
FileStatus status = null;
|
||||
try {
|
||||
status = fs.getFileStatus(path);
|
||||
} catch (FileNotFoundException e) {} // ignore FNF
|
||||
return status;
|
||||
}
|
||||
|
||||
/**
|
||||
* Convenience ctor that extracts the path from the given file status
|
||||
* @param fs the FileSystem for the FileStatus
|
||||
* @param stat the FileStatus
|
||||
*/
|
||||
public PathData(FileSystem fs, FileStatus stat) {
|
||||
this(fs, stat.getPath(), stat);
|
||||
}
|
||||
|
||||
/**
|
||||
* Updates the paths's file status
|
||||
* @return the updated FileStatus
|
||||
* @throws IOException if anything goes wrong...
|
||||
*/
|
||||
public FileStatus refreshStatus() throws IOException {
|
||||
stat = fs.getFileStatus(path);
|
||||
return stat;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a list of PathData objects of the items contained in the given
|
||||
* directory.
|
||||
* @return list of PathData objects for its children
|
||||
* @throws IOException if anything else goes wrong...
|
||||
*/
|
||||
public PathData[] getDirectoryContents() throws IOException {
|
||||
if (!stat.isDirectory()) {
|
||||
throw new IOException(path + ": Not a directory");
|
||||
}
|
||||
|
||||
FileStatus[] stats = fs.listStatus(path);
|
||||
PathData[] items = new PathData[stats.length];
|
||||
for (int i=0; i < stats.length; i++) {
|
||||
items[i] = new PathData(fs, stats[i]);
|
||||
}
|
||||
return items;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the printable version of the path that is just the
|
||||
* filesystem path instead of the full uri
|
||||
* @return String of the path
|
||||
*/
|
||||
public String toString() {
|
||||
return path.toUri().getPath();
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,47 @@
|
|||
/**
|
||||
* 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.hadoop.fs.shell;
|
||||
|
||||
import org.apache.hadoop.conf.Configuration;
|
||||
import org.apache.hadoop.fs.FileSystem;
|
||||
import org.apache.hadoop.fs.Path;
|
||||
import org.junit.BeforeClass;
|
||||
import org.junit.Test;
|
||||
import static org.junit.Assert.*;
|
||||
|
||||
public class TestPathData {
|
||||
protected static Configuration conf;
|
||||
protected static FileSystem fs;
|
||||
protected static Path dir;
|
||||
|
||||
@BeforeClass
|
||||
public static void initialize() throws Exception {
|
||||
conf = new Configuration();
|
||||
fs = FileSystem.getLocal(conf);
|
||||
dir = new Path("/tmp");
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testWithPath() throws Exception {
|
||||
PathData item = new PathData(fs, dir);
|
||||
assertEquals(fs, item.fs);
|
||||
assertEquals(dir, item.path);
|
||||
assertTrue(item.stat != null);
|
||||
assertTrue(item.stat.isDirectory());
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue