alluxio.cli.fs.command.StatCommand.java Source code

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Here is the source code for alluxio.cli.fs.command.StatCommand.java

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/*
 * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
 * (the "License"). You may not use this work except in compliance with the License, which is
 * available at www.apache.org/licenses/LICENSE-2.0
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied, as more fully set forth in the License.
 *
 * See the NOTICE file distributed with this work for information regarding copyright ownership.
 */

package alluxio.cli.fs.command;

import alluxio.AlluxioURI;
import alluxio.cli.CommandUtils;
import alluxio.client.block.AlluxioBlockStore;
import alluxio.client.file.FileSystem;
import alluxio.client.file.URIStatus;
import alluxio.exception.AlluxioException;
import alluxio.exception.status.InvalidArgumentException;

import com.google.common.base.Preconditions;
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.Options;

import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.annotation.concurrent.ThreadSafe;

/**
 * Displays the path's info.
 * If path is a directory it displays the directory's info.
 * If path is a file, it displays the file's all blocks info.
 */
@ThreadSafe
public final class StatCommand extends AbstractFileSystemCommand {
    /**
     * @param fs the filesystem of Alluxio
     */
    public StatCommand(FileSystem fs) {
        super(fs);
    }

    @Override
    public String getCommandName() {
        return "stat";
    }

    @Override
    public Options getOptions() {
        return new Options().addOption(Option.builder("f").required(false).hasArg().desc("format").build());
    }

    @Override
    protected void runPlainPath(AlluxioURI path, CommandLine cl) throws AlluxioException, IOException {
        URIStatus status = mFileSystem.getStatus(path);
        if (cl.hasOption('f')) {
            System.out.println(formatOutput(cl, status));
        } else {
            if (status.isFolder()) {
                System.out.println(path + " is a directory path.");
                System.out.println(status);
            } else {
                System.out.println(path + " is a file path.");
                System.out.println(status);
                AlluxioBlockStore blockStore = AlluxioBlockStore.create();
                List<Long> blockIds = status.getBlockIds();
                if (blockIds.isEmpty()) {
                    System.out.println("This file does not contain any blocks.");
                } else {
                    System.out.println("Containing the following blocks: ");
                    for (long blockId : blockIds) {
                        System.out.println(blockStore.getInfo(blockId));
                    }
                }
            }
        }
    }

    @Override
    public int run(CommandLine cl) throws AlluxioException, IOException {
        String[] args = cl.getArgs();
        AlluxioURI path = new AlluxioURI(args[0]);
        runWildCardCmd(path, cl);

        return 0;
    }

    @Override
    public String getUsage() {
        return "stat [-f <format>] <path>";
    }

    @Override
    public String getDescription() {
        return "Displays info for the specified path both file and directory."
                + " Specify -f to display info in given format:" + "   \"%N\": name of the file;"
                + "   \"%z\": size of file in bytes;" + "   \"%u\": owner;" + "   \"%g\": group name of owner;"
                + "   \"%y\" or \"%Y\": modification time," + " %y shows 'yyyy-MM-dd HH:mm:ss' (the UTC date),"
                + " %Y it shows milliseconds since January 1, 1970 UTC;"
                + "   \"%b\": Number of blocks allocated for file";
    }

    @Override
    public void validateArgs(CommandLine cl) throws InvalidArgumentException {
        CommandUtils.checkNumOfArgsEquals(this, cl, 1);
    }

    private static final String FORMAT_REGEX = "%([bguyzNY])";
    private static final Pattern FORMAT_PATTERN = Pattern.compile(FORMAT_REGEX);

    private String formatOutput(CommandLine cl, URIStatus status) {
        String format = cl.getOptionValue('f');
        int formatLen = format.length();

        StringBuilder output = new StringBuilder();
        Matcher m = FORMAT_PATTERN.matcher(format);
        int i = 0;
        while (i < formatLen && m.find(i)) {
            if (m.start() != i) {
                output.append(format.substring(i, m.start()));
            }
            output.append(getField(m, status));
            i = m.end();
        }
        if (i < formatLen) {
            output.append(format.substring(i));
        }
        return output.toString();
    }

    private String getField(Matcher m, URIStatus status) {
        char formatSpecifier = m.group(1).charAt(0);
        String resp = null;
        switch (formatSpecifier) {
        case 'b':
            resp = status.isFolder() ? "NA" : String.valueOf(status.getFileBlockInfos().size());
            break;
        case 'g':
            resp = status.getGroup();
            break;
        case 'u':
            resp = status.getOwner();
            break;
        case 'y':
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            resp = sdf.format(new Date(status.getLastModificationTimeMs()));
            break;
        case 'z':
            resp = status.isFolder() ? "NA" : String.valueOf(status.getLength());
            break;
        case 'N':
            resp = status.getName();
            break;
        case 'Y':
            resp = String.valueOf(status.getLastModificationTimeMs());
            break;
        default:
            Preconditions.checkArgument(false, "Unknown format specifier %c", formatSpecifier);
        }
        return resp;
    }
}