io.druid.server.initialization.PropertiesModule.java Source code

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Here is the source code for io.druid.server.initialization.PropertiesModule.java

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/*
 * Druid - a distributed column store.
 * Copyright (C) 2012, 2013  Metamarkets Group Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

package io.druid.server.initialization;

import com.google.common.base.Charsets;
import com.google.common.base.Throwables;
import com.google.common.io.Closeables;
import com.google.inject.Binder;
import com.google.inject.Module;
import com.metamx.common.logger.Logger;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Properties;

/**
 */
public class PropertiesModule implements Module {
    private static final Logger log = new Logger(PropertiesModule.class);

    private final String propertiesFile;

    public PropertiesModule(String propertiesFile) {
        this.propertiesFile = propertiesFile;
    }

    @Override
    public void configure(Binder binder) {
        final Properties fileProps = new Properties();
        Properties systemProps = System.getProperties();

        Properties props = new Properties(fileProps);
        props.putAll(systemProps);

        InputStream stream = ClassLoader.getSystemResourceAsStream(propertiesFile);
        try {
            if (stream == null) {
                File workingDirectoryFile = new File(
                        systemProps.getProperty("druid.properties.file", propertiesFile));
                if (workingDirectoryFile.exists()) {
                    stream = new BufferedInputStream(new FileInputStream(workingDirectoryFile));
                }
            }

            if (stream != null) {
                log.info("Loading properties from %s", propertiesFile);
                try {
                    fileProps.load(new InputStreamReader(stream, Charsets.UTF_8));
                } catch (IOException e) {
                    throw Throwables.propagate(e);
                }
            }
        } catch (FileNotFoundException e) {
            log.wtf(e, "This can only happen if the .exists() call lied.  That's f'd up.");
        } finally {
            Closeables.closeQuietly(stream);
        }

        binder.bind(Properties.class).toInstance(props);
    }
}