org.apache.parquet.tools.command.ShowSchemaCommand.java Source code

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Here is the source code for org.apache.parquet.tools.command.ShowSchemaCommand.java

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/* 
 * 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.parquet.tools.command;

import java.text.DecimalFormat;

import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.OptionBuilder;
import org.apache.commons.cli.Options;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

import org.apache.parquet.hadoop.ParquetFileReader;
import org.apache.parquet.hadoop.metadata.ParquetMetadata;
import org.apache.parquet.hadoop.util.HiddenFileFilter;
import org.apache.parquet.schema.MessageType;
import org.apache.parquet.tools.Main;
import org.apache.parquet.tools.util.MetadataUtils;
import org.apache.parquet.tools.util.PrettyPrintWriter;

import static org.apache.parquet.format.converter.ParquetMetadataConverter.NO_FILTER;

public class ShowSchemaCommand extends ArgsOnlyCommand {
    public static final String[] USAGE = new String[] { "<input>",
            "where <input> is the parquet file containing the schema to show" };

    public static final Options OPTIONS;
    static {
        OPTIONS = new Options();
        Option help = OptionBuilder.withLongOpt("detailed")
                .withDescription("Show detailed information about the schema.").create('d');
        OPTIONS.addOption(help);
    }

    public ShowSchemaCommand() {
        super(1, 1);
    }

    @Override
    public String[] getUsageDescription() {
        return USAGE;
    }

    @Override
    public Options getOptions() {
        return OPTIONS;
    }

    @Override
    public void execute(CommandLine options) throws Exception {
        super.execute(options);

        String[] args = options.getArgs();
        String input = args[0];

        Configuration conf = new Configuration();
        ParquetMetadata metaData;

        Path path = new Path(input);
        FileSystem fs = path.getFileSystem(conf);
        Path file;
        if (fs.isDirectory(path)) {
            FileStatus[] statuses = fs.listStatus(path, HiddenFileFilter.INSTANCE);
            if (statuses.length == 0) {
                throw new RuntimeException("Directory " + path.toString() + " is empty");
            }
            file = statuses[0].getPath();
        } else {
            file = path;
        }
        metaData = ParquetFileReader.readFooter(conf, file, NO_FILTER);
        MessageType schema = metaData.getFileMetaData().getSchema();

        Main.out.println(schema);
        if (options.hasOption('d')) {
            PrettyPrintWriter out = PrettyPrintWriter.stdoutPrettyPrinter().build();
            MetadataUtils.showDetails(out, metaData);
        }
    }
}