ingo@1122: package de.intevation.gnv.geobackend.config;
ingo@1122: 
ingo@1122: import de.intevation.gnv.geobackend.base.connectionpool.ConnectionPoolFactory;
ingo@1122: 
ingo@1122: import de.intevation.gnv.geobackend.base.query.container.QueryContainerFactory;
ingo@1122: 
ingo@1122: import de.intevation.gnv.geobackend.base.query.container.exception.QueryContainerException;
ingo@1122: 
ingo@1122: import de.intevation.gnv.geobackend.util.XMLUtils;
ingo@1122: 
ingo@1122: import java.io.FileInputStream;
ingo@1122: import java.io.FileNotFoundException;
ingo@1122: import java.io.IOException;
ingo@1122: import java.io.InputStream;
ingo@1122: 
ingo@1122: import java.util.Properties;
ingo@1122: 
ingo@1122: import javax.xml.xpath.XPathConstants;
ingo@1122: 
ingo@1122: import org.apache.log4j.Logger;
ingo@1122: 
ingo@1122: import org.w3c.dom.Document;
ingo@1122: import org.w3c.dom.Node;
ingo@1122: import org.w3c.dom.NodeList;
ingo@1122: 
ingo@1122: /**
ingo@1122:  * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
ingo@1122:  */
ingo@1122: public final class Configuration {
ingo@1122: 
ingo@1122:     public static final String CONFIGURATION_ROOT  = "geo-backend";
ingo@1122:     public static final String XPATH_QUERIES       = "query-configuration";
ingo@1122:     public static final String XPATH_BACKEND       = "backend-configuration";
ingo@1122:     public static final String XPATH_CACHE         = "cache";
ingo@1122:     public static final String XPATH_CACHE_ENABLED = "@enabled";
ingo@1122:     public static final String XPATH_CACHE_CONFIG  = "configuration";
ingo@1122: 
ingo@1122:     private static Logger logger = Logger.getLogger(Configuration.class);
ingo@1122: 
ingo@1122:     private static Configuration instance;
ingo@1122: 
ingo@1122:     private Node   config;
ingo@1122:     private String configDir;
ingo@1122:     private String placeholder;
ingo@1122: 
ingo@1122:     private boolean cacheEnabled;
ingo@1122:     private String  cacheConfiguration;
ingo@1122: 
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Returns an instance of Configuration.
ingo@1122:      *
ingo@1122:      * @return an instance of Configuration.
ingo@1122:      */
ingo@1122:     public static Configuration getInstance() {
ingo@1122:         if (instance == null)
ingo@1122:             instance = new Configuration();
ingo@1122: 
ingo@1122:         return instance;
ingo@1122:     }
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Constructor that creates a new Configuration object with disabled cache.
ingo@1122:      */
ingo@1122:     public Configuration() {
ingo@1122:         cacheEnabled = false;
ingo@1122:     }
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Initialize the geo-backend before it is ready to be used. This method
ingo@1122:      * calls other <i>init*</i> methods.
ingo@1122:      *
ingo@1122:      * @param conf A configuration document. This document should contain a node
ingo@1122:      * <i>geo-backend</i>. If there are more nodes named <i>geo-backend</i>, the
ingo@1122:      * first node is used.
ingo@1122:      * @param configDir The path to the root configuration directory.
ingo@1122:      * @param placeholder The placeholder used in the configuration document for
ingo@1122:      * the root configuration directory.
ingo@1122:      */
ingo@1122:     public void init(Document conf, String configDir, String placeholder)
ingo@1122:     throws QueryContainerException, FileNotFoundException, IOException
ingo@1122:     {
ingo@1122:         this.config      = conf;
ingo@1122:         this.configDir   = configDir;
ingo@1122:         this.placeholder = placeholder;
ingo@1122: 
ingo@1122:         NodeList root = conf.getElementsByTagName(CONFIGURATION_ROOT);
ingo@1122:         if (root == null || root.getLength() == 0) {
ingo@1122:             logger.error("No valid configuration for this geobackend given!");
ingo@1122:             return;
ingo@1122:         }
ingo@1122: 
ingo@1122:         initQueries(root.item(0));
ingo@1122:         initConnection(root.item(0));
ingo@1122:         initCache(root.item(0));
ingo@1122:     }
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Initialize sql statements.
ingo@1122:      *
ingo@1122:      * @param conf The geo-backend configuration node.
ingo@1122:      */
ingo@1122:     protected void initQueries(Node conf)
ingo@1122:     throws FileNotFoundException, IOException, QueryContainerException
ingo@1122:     {
ingo@1122:         String queriesFile = (String) XMLUtils.xpath(
ingo@1122:             conf, XPATH_QUERIES, XPathConstants.STRING, null);
ingo@1122: 
ingo@1122:         queriesFile = replaceConfigDir(queriesFile);
ingo@1122:         logger.info("Initialize queries: " + queriesFile);
ingo@1122: 
ingo@1122:         Properties queries        = getProperties(queriesFile);
ingo@1122:         QueryContainerFactory qcf = QueryContainerFactory.getInstance();
ingo@1122:         qcf.initializeQueryContainer(queries);
ingo@1122:     }
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Initialize necessary objects used for the database connection.
ingo@1122:      *
ingo@1122:      * @param connection The geo-backend configuration node.
ingo@1122:      */
ingo@1122:     protected void initConnection(Node connection)
ingo@1122:     throws FileNotFoundException, IOException
ingo@1122:     {
ingo@1122:         String config = (String)XMLUtils.xpath(
ingo@1122:             connection, XPATH_BACKEND, XPathConstants.STRING, null);
ingo@1122: 
ingo@1122:         config = replaceConfigDir(config);
ingo@1122:         logger.info("Initialize database connection: " + config);
ingo@1122: 
ingo@1122:         Properties properties     = getProperties(config);
ingo@1122:         ConnectionPoolFactory cpf = ConnectionPoolFactory.getInstance();
ingo@1122:         cpf.initializeConnectionPool(properties);
ingo@1122:     }
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Initialize necessary objects used for the sql cache.
ingo@1122:      *
ingo@1122:      * @param conf The geo-backend configuration node.
ingo@1122:      */
ingo@1122:     protected void initCache(Node conf) {
ingo@1122:         Node cache = (Node) XMLUtils.xpath(
ingo@1122:             conf, XPATH_CACHE, XPathConstants.NODE, null);
ingo@1122: 
ingo@1122:         String on = (String) XMLUtils.xpath(
ingo@1122:             cache, XPATH_CACHE_ENABLED, XPathConstants.STRING, null);
ingo@1122: 
ingo@1122:         boolean enabled = Boolean.parseBoolean(on);
ingo@1122: 
ingo@1122:         if (enabled) {
ingo@1122:             String config = (String) XMLUtils.xpath(
ingo@1122:                 cache, XPATH_CACHE_CONFIG, XPathConstants.STRING, null);
ingo@1122: 
ingo@1122:             if (config != null && config.length() > 0) {
ingo@1122:                 config = replaceConfigDir(config);
ingo@1122:                 logger.info("Initialize sql cache with config: " + config);
ingo@1122: 
ingo@1122:                 this.cacheConfiguration = config;
ingo@1122:                 this.cacheEnabled       = true;
ingo@1122:             }
ingo@1122:             else {
ingo@1122:                 logger.error("SQL cache is enabled, " +
ingo@1122:                     "but no configuration was found.");
ingo@1122:             }
ingo@1122:         }
ingo@1122:         else {
ingo@1122:             logger.info("SQL cache is disabled.");
ingo@1122:         }
ingo@1122:     }
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Replace placeholder in the configuration. Placeholder are used for the
ingo@1122:      * base configuration directory.
ingo@1122:      *
ingo@1122:      * @param path A string that might contain placeholders.
ingo@1122:      *
ingo@1122:      * @return <i>path</i> with replaced placeholder.
ingo@1122:      */
ingo@1122:     protected String replaceConfigDir(String path) {
ingo@1122:         return path.replace(placeholder, configDir);
ingo@1122:     }
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Read a file that contains properties and return a Java Properties object.
ingo@1122:      *
ingo@1122:      * @param path Path to a properties file.
ingo@1122:      *
ingo@1122:      * @return the properties contained in the file.
ingo@1122:      */
ingo@1122:     protected Properties getProperties(String path)
ingo@1122:     throws    FileNotFoundException, IOException
ingo@1122:     {
ingo@1122:         InputStream inputStream = null;
ingo@1122: 
ingo@1122:         try {
ingo@1122:             inputStream = new FileInputStream(path);
ingo@1122:             Properties properties = new Properties();
ingo@1122:             properties.load(inputStream);
ingo@1122: 
ingo@1122:             return properties;
ingo@1122:         }
ingo@1122:         finally {
ingo@1122:             if (inputStream != null) {
ingo@1122:                 try {
ingo@1122:                     inputStream.close();
ingo@1122:                 }
ingo@1122:                 catch (IOException ioe) {
ingo@1122:                 }
ingo@1122:             }
ingo@1122:         }
ingo@1122:     }
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Returns the state of the cache.
ingo@1122:      *
ingo@1122:      * @return true if sql queries are cache, otherwise false.
ingo@1122:      */
ingo@1122:     public boolean isCacheEnabled() {
ingo@1122:         return cacheEnabled;
ingo@1122:     }
ingo@1122: 
ingo@1122: 
ingo@1122:     /**
ingo@1122:      * Returns the path of the cache configuration file.
ingo@1122:      *
ingo@1122:      * @return configuration path.
ingo@1122:      */
ingo@1122:     public String getCacheConfiguration() {
ingo@1122:         return cacheConfiguration;
ingo@1122:     }
ingo@1122: }
ingo@1122: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :