XML Config Cache Helper. Issue #8.

Author: jonathanaustin

pom.xml

@@ -52,6 +52,20 @@
 				<version>1.0.0</version>
 			</dependency>
 
+			<!-- Injection interface. JSR 330 -->
+			<dependency>
+				<groupId>javax.inject</groupId>
+				<artifactId>javax.inject</artifactId>
+				<version>1</version>
+			</dependency>
+
+			<!-- Config -->
+			<dependency>
+				<groupId>com.github.bordertech.config</groupId>
+				<artifactId>config</artifactId>
+				<version>1.0.1</version>
+			</dependency>
+
 			<!-- Logging -->
 			<dependency>
 				<groupId>org.slf4j</groupId>

taskmaster-cache-helper/pom.xml

@@ -38,6 +38,19 @@
 			<artifactId>cache-api</artifactId>
 		</dependency>
 
+		<!-- Config -->
+		<dependency>
+			<groupId>com.github.bordertech.config</groupId>
+			<artifactId>config</artifactId>
+		</dependency>
+
+		<!-- Injection interface. JSR 330 -->
+		<dependency>
+			<groupId>javax.inject</groupId>
+			<artifactId>javax.inject</artifactId>
+			<scope>provided</scope>
+		</dependency>
+
 		<!-- Servlet Interface -->
 		<dependency>
 			<groupId>javax.servlet</groupId>

taskmaster-cache-helper/src/main/java/com/github/bordertech/taskmaster/cache/CacheHelperXmlConfigImpl.java

@@ -0,0 +1,75 @@
+package com.github.bordertech.taskmaster.cache;
+
+import com.github.bordertech.config.Config;
+import java.net.URI;
+import java.net.URISyntaxException;
+import javax.cache.Cache;
+import javax.cache.CacheManager;
+import javax.cache.Caching;
+import javax.cache.configuration.Configuration;
+import javax.cache.expiry.Duration;
+import javax.cache.spi.CachingProvider;
+import javax.inject.Singleton;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+/**
+ * Cache Helper that relies on the cache config in a xml file.
+ */
+@Singleton
+public class CacheHelperXmlConfigImpl implements CacheHelper {
+
+	private static final Log LOGGER = LogFactory.getLog(CacheHelperXmlConfigImpl.class);
+
+	private static final CacheManager MANAGER;
+
+	static {
+		// Load cache configfile location (default tm-cache.xml)
+		String config = Config.getInstance().getString("bordertech.taskmaster.cache.config", "/tm-cache.xml");
+		LOGGER.info("Loading cache config [" + config + "].");
+		URI uri;
+		try {
+			uri = CacheHelperXmlConfigImpl.class.getResource(config).toURI();
+		} catch (URISyntaxException e) {
+			throw new IllegalStateException("Could not load cache config [" + config + "]." + e.getMessage(), e);
+		}
+		CachingProvider cachingProvider = Caching.getCachingProvider();
+		MANAGER = cachingProvider.getCacheManager(uri, CacheHelperXmlConfigImpl.class.getClassLoader());
+	}
+
+	@Override
+	public synchronized <K, V> Cache<K, V> getOrCreateCache(final String name, final Class<K> keyClass,
+			final Class<V> valueClass, final Duration duration) {
+		// Ignore duration
+		return handleGetCache(name, keyClass, valueClass);
+	}
+
+	@Override
+	public synchronized <K, V> Cache<K, V> getOrCreateCache(final String name, final Class<K> keyClass,
+			final Class<V> valueClass, final Configuration<K, V> config) {
+		// Ignore config
+		return handleGetCache(name, keyClass, valueClass);
+	}
+
+	/**
+	 * Get the pre-configured cache.
+	 *
+	 * @param name the cache name
+	 * @param keyClass the cache key class
+	 * @param valueClass the cache entry class
+	 * @return the cache instance
+	 * @param <K> the cache key type
+	 * @param <V> the cache entry type
+	 */
+	protected synchronized <K, V> Cache<K, V> handleGetCache(final String name, final Class<K> keyClass,
+			final Class<V> valueClass) {
+		return MANAGER.getCache(name, keyClass, valueClass);
+	}
+
+	/**
+	 * @return the XML Configured cache manager
+	 */
+	protected final CacheManager getManager() {
+		return MANAGER;
+	}
+}