it.geosolutions.geobatch.catalog.file.GeoBatchDataDirAwarePropertyOverrideConfigurer.java Source code

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Here is the source code for it.geosolutions.geobatch.catalog.file.GeoBatchDataDirAwarePropertyOverrideConfigurer.java

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/* Copyright (c) 2011 GeoSolutions - http://www.geo-solutions.it/.  All rights reserved.
 * This code is licensed under the GPL 2.0 license, available at the root
 * application directory.
 */
package it.geosolutions.geobatch.catalog.file;

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

import org.apache.log4j.LogManager;
import org.springframework.beans.factory.config.PropertyOverrideConfigurer;
import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer;

/**
 * 
 * GeoServer's specific subclass for {@link PropertyPlaceholderConfigurer} Spring bean to load properties file.
 * 
 * <p> This class is a special {@link PropertyPlaceholderConfigurer} that:
 * <ol>
 *   <li> By default load properties from a specific file inside a specific dir of the GeoServer data dir. Hence it is aware of the GeoServer data dir. This id done via setting internally {@link #setLocalOverride(boolean)} to <code>true</code> </li>
 *   <li> It still allows users to specify locations from where loading the properties. In this case we must set localovveride property to false though.
 * </ol>
 * @author Simone Giannecchini, GeoSolutions SAS.
 *
 */
public abstract class GeoBatchDataDirAwarePropertyOverrideConfigurer extends PropertyOverrideConfigurer {

    /**Logger.*/
    static final private org.apache.log4j.Logger LOGGER = LogManager
            .getLogger(GeoBatchDataDirAwarePropertyOverrideConfigurer.class);

    /**This object mediates access to the GeoServer data directory.**/
    protected final DataDirHandler dataDirectoryHandler;

    /** 
     * Constructor.
     * 
     * <p> Allows subclasses or users to specify from which directory which properties files to load.
     * 
     * @param dataDirectory a valid {@link GeoServerDataDirectory}. Cannot be <code>null</code>.
     * @param parentDirectory An absolute path to the directory where to look for properties files.
     * @param propertiesFiles List of names (with extension) of properties files to load.
     */
    public GeoBatchDataDirAwarePropertyOverrideConfigurer(final DataDirHandler dataDirectory,
            final boolean localOverride) {
        //checks
        if (dataDirectory == null) {
            throw new IllegalArgumentException(
                    "Unable to proceed with the placeholder initialization as the provided DataDirHandler is null!");
        }
        this.dataDirectoryHandler = dataDirectory;

        // localOverride to true, so that what we do here takes precedence over external properties
        setLocalOverride(localOverride);

        //
        // set the properties
        //
        // load from properties file   
        final Properties props = getCustomProperties();
        if (props != null) {
            if (LOGGER.isTraceEnabled()) {
                LOGGER.trace("Trying to set default properties:\n" + props);
            }
            setProperties(props);
        }
    }

    /**
     * Method that subclasses should implement to inject custom default properties in his override.
     * 
     * @return {@link Properties} to set as defaults
     */
    protected abstract Properties getCustomProperties();

    /**
     * Tries to find the provided properties file and then returns its properties.
     * 
     * @param propertiesFile the {@link File} to load from. Must exists and be readable.
     * @throws IOException in case something bad happens trying to read the proeprties from the file.
     * 
     */
    protected static Properties loadProperties(final File propertiesFile) throws IOException {
        // checks on provided file
        if (!(propertiesFile != null && propertiesFile.exists() && propertiesFile.isFile()
                && propertiesFile.canRead())) {
            return null;
        }
        // load the file
        InputStream is = null;
        try {
            is = new BufferedInputStream(new FileInputStream(propertiesFile));
            final Properties properties = new Properties();
            properties.load(is);
            return properties;
        } finally {
            // close
            if (is != null) {
                try {
                    is.close();
                } catch (Exception e) {
                    if (LOGGER.isTraceEnabled()) {
                        LOGGER.trace(e.getLocalizedMessage(), e);
                    }
                }
            }
        }
    }
}