com.sitewhere.configuration.FileSystemGlobalConfigurationResolver.java Source code

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Here is the source code for com.sitewhere.configuration.FileSystemGlobalConfigurationResolver.java

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/*
 * Copyright (c) SiteWhere, LLC. All rights reserved. http://www.sitewhere.com
 *
 * The software in this package is published under the terms of the CPAL v1.0
 * license, a copy of which has been included with this distribution in the
 * LICENSE.txt file.
 */
package com.sitewhere.configuration;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URI;

import org.apache.commons.io.IOUtils;
import org.apache.log4j.Logger;

import com.sitewhere.spi.SiteWhereException;
import com.sitewhere.spi.configuration.IGlobalConfigurationResolver;
import com.sitewhere.spi.system.IVersion;

/**
 * Resolves global configuration settings within a Tomcat instance.
 * 
 * @author Derek
 */
public abstract class FileSystemGlobalConfigurationResolver implements IGlobalConfigurationResolver {

    /** Static logger instance */
    public static Logger LOGGER = Logger.getLogger(FileSystemGlobalConfigurationResolver.class);

    /** Folder name for global resources */
    public static final String GLOBAL_FOLDER_NAME = "global";

    /** Folder name for global scripts */
    public static final String SCRIPTS_FOLDER_NAME = "scripts";

    /** File name for SiteWhere global configuration file */
    public static final String GLOBAL_CONFIG_FILE_NAME = "sitewhere-server.xml";

    /** File name for SiteWhere state information in JSON format */
    public static final String STATE_FILE_NAME = "sitewhere-state.json";

    /**
     * Get the folder on the filesystem that contains global configuration information.
     * 
     * @return
     * @throws SiteWhereException
     */
    public abstract File getGlobalConfigurationFolder() throws SiteWhereException;

    /*
     * (non-Javadoc)
     * 
     * @see
     * com.sitewhere.spi.configuration.IConfigurationResolver#getGlobalConfiguration(com
     * .sitewhere.spi.system.IVersion)
     */
    @Override
    public byte[] getGlobalConfiguration(IVersion version) throws SiteWhereException {
        File sitewhereConf = getGlobalConfigurationFolder();
        File global = new File(sitewhereConf, GLOBAL_CONFIG_FILE_NAME);
        return getFileQuietly(global);
    }

    /**
     * Get contents of a file as a byte array.
     * 
     * @param file
     * @return
     * @throws SiteWhereException
     */
    public static byte[] getFileQuietly(File file) throws SiteWhereException {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        try {
            FileInputStream in = new FileInputStream(file);
            IOUtils.copy(in, out);
            IOUtils.closeQuietly(in);
            IOUtils.closeQuietly(out);
            return out.toByteArray();
        } catch (FileNotFoundException e) {
            throw new SiteWhereException(e);
        } catch (IOException e) {
            throw new SiteWhereException(e);
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.sitewhere.spi.configuration.IConfigurationResolver#resolveServerState(com.
     * sitewhere .spi.system.IVersion)
     */
    @Override
    public byte[] resolveServerState(IVersion version) throws SiteWhereException {
        File stateFile = new File(getGlobalConfigurationFolder(), STATE_FILE_NAME);
        if (!stateFile.exists()) {
            return null;
        }
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        try {
            FileInputStream in = new FileInputStream(stateFile);
            IOUtils.copy(in, out);
            IOUtils.closeQuietly(in);
            IOUtils.closeQuietly(out);
            return out.toByteArray();
        } catch (FileNotFoundException e) {
            throw new SiteWhereException(e);
        } catch (IOException e) {
            throw new SiteWhereException(e);
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.sitewhere.spi.configuration.IConfigurationResolver#storeServerState(com.
     * sitewhere .spi.system.IVersion, byte[])
     */
    @Override
    public void storeServerState(IVersion version, byte[] data) throws SiteWhereException {
        File stateFile = new File(getGlobalConfigurationFolder(), STATE_FILE_NAME);
        if (!stateFile.exists()) {
            try {
                if (!stateFile.createNewFile()) {
                    throw new SiteWhereException("Unable to create file for storing server state.");
                }
            } catch (IOException e) {
                throw new SiteWhereException(
                        "Unable to create file for storing server state: " + stateFile.getAbsolutePath(), e);
            }
        }
        try {
            ByteArrayInputStream in = new ByteArrayInputStream(data);
            FileOutputStream out = new FileOutputStream(stateFile);
            IOUtils.copy(in, out);
            IOUtils.closeQuietly(in);
            IOUtils.closeQuietly(out);
        } catch (IOException e) {
            throw new SiteWhereException("Unable to save server state: " + stateFile.getAbsolutePath(), e);
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see com.sitewhere.spi.configuration.IConfigurationResolver#getConfigurationRoot()
     */
    @Override
    public URI getConfigurationRoot() throws SiteWhereException {
        return getGlobalConfigurationFolder().toURI();
    }
}