added prefix for guava cache classes

scm-webapp/src/main/java/sonia/scm/cache/GuavaCacheConfigurationReader.java

@@ -0,0 +1,297 @@
+/**
+ * Copyright (c) 2010, Sebastian Sdorra All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer. 2. Redistributions in
+ * binary form must reproduce the above copyright notice, this list of
+ * conditions and the following disclaimer in the documentation and/or other
+ * materials provided with the distribution. 3. Neither the name of SCM-Manager;
+ * nor the names of its contributors may be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * http://bitbucket.org/sdorra/scm-manager
+ *
+ */
+
+
+
+package sonia.scm.cache;
+
+//~--- non-JDK imports --------------------------------------------------------
+
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Maps;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import sonia.scm.SCMContext;
+
+//~--- JDK imports ------------------------------------------------------------
+
+import java.io.File;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+
+import javax.xml.bind.JAXBContext;
+import javax.xml.bind.JAXBException;
+
+/**
+ *
+ * @author Sebastian Sdorra
+ */
+public class GuavaCacheConfigurationReader
+{
+
+  /** Field description */
+  private static final String DEFAULT = "/config/gcache.xml";
+
+  /** Field description */
+  private static final String MANUAL_RESOURCE =
+    "ext".concat(File.separator).concat("gcache.xml");
+
+  /** Field description */
+  private static final String MODULE_RESOURCES = "/META-INF/scm/gcache.xml";
+
+  /**
+   * the logger for CacheConfigurationReader
+   */
+  private static final Logger logger =
+    LoggerFactory.getLogger(GuavaCacheConfigurationReader.class);
+
+  //~--- constructors ---------------------------------------------------------
+
+  /**
+   * Constructs ...
+   *
+   */
+  public GuavaCacheConfigurationReader()
+  {
+    try
+    {
+      this.context =
+        JAXBContext.newInstance(GuavaCacheManagerConfiguration.class);
+    }
+    catch (JAXBException ex)
+    {
+      throw new CacheException(
+        "could not create jaxb context for cache configuration", ex);
+    }
+  }
+
+  //~--- methods --------------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  public GuavaCacheManagerConfiguration read()
+  {
+    URL defaultConfigUrl = getDefaultResource();
+
+    if (defaultConfigUrl == null)
+    {
+      throw new IllegalStateException(
+        "could not find default cache configuration");
+    }
+
+    GuavaCacheManagerConfiguration config = readConfiguration(defaultConfigUrl,
+                                              true);
+
+    Iterator<URL> it = getModuleResources();
+
+    while (it.hasNext())
+    {
+      GuavaCacheManagerConfiguration moduleConfig =
+        readConfiguration(it.next(), false);
+
+      if (moduleConfig != null)
+      {
+        config = merge(config, moduleConfig);
+      }
+    }
+
+    File manualFile = getManualFileResource();
+
+    if (manualFile.exists())
+    {
+      try
+      {
+        GuavaCacheManagerConfiguration manualConfig =
+          readConfiguration(manualFile.toURI().toURL(), false);
+
+        config = merge(config, manualConfig);
+      }
+      catch (MalformedURLException ex)
+      {
+        logger.error("malformed url", ex);
+      }
+    }
+    else
+    {
+      logger.warn("could not find manual configuration at {}", manualFile);
+    }
+
+    return config;
+  }
+
+  //~--- get methods ----------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  @VisibleForTesting
+  protected URL getDefaultResource()
+  {
+    return GuavaCacheConfigurationReader.class.getResource(DEFAULT);
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  @VisibleForTesting
+  protected File getManualFileResource()
+  {
+    return new File(SCMContext.getContext().getBaseDirectory(),
+      MANUAL_RESOURCE);
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param path
+   *
+   * @return
+   */
+  @VisibleForTesting
+  protected Iterator<URL> getModuleResources()
+  {
+    return CacheConfigurations.findModuleResources(
+      EhCacheConfigurationReader.class, MODULE_RESOURCES);
+  }
+
+  //~--- methods --------------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @param caches
+   *
+   * @return
+   */
+  private Map<String, GuavaNamedCacheConfiguration> createNamedCacheMap(
+    List<GuavaNamedCacheConfiguration> caches)
+  {
+    Map<String, GuavaNamedCacheConfiguration> map = Maps.newLinkedHashMap();
+
+    for (GuavaNamedCacheConfiguration ncc : caches)
+    {
+      map.put(ncc.getName(), ncc);
+    }
+
+    return map;
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param config
+   * @param other
+   *
+   * @return
+   */
+  private GuavaCacheManagerConfiguration merge(
+    GuavaCacheManagerConfiguration config, GuavaCacheManagerConfiguration other)
+  {
+    GuavaCacheConfiguration defaultCache = config.getDefaultCache();
+    Map<String, GuavaNamedCacheConfiguration> namedCaches =
+      createNamedCacheMap(config.getCaches());
+
+    if (other.getDefaultCache() != null)
+    {
+      defaultCache = other.getDefaultCache();
+    }
+
+    List<GuavaNamedCacheConfiguration> otherNamedCaches = other.getCaches();
+
+    for (GuavaNamedCacheConfiguration ncc : otherNamedCaches)
+    {
+      namedCaches.put(ncc.getName(), ncc);
+    }
+
+    return new GuavaCacheManagerConfiguration(defaultCache,
+      ImmutableList.copyOf(namedCaches.values()));
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param url
+   * @param fail
+   *
+   * @return
+   */
+  private GuavaCacheManagerConfiguration readConfiguration(URL url,
+    boolean fail)
+  {
+    GuavaCacheManagerConfiguration config = null;
+
+    try
+    {
+      config =
+        (GuavaCacheManagerConfiguration) context.createUnmarshaller().unmarshal(
+          url);
+    }
+    catch (JAXBException ex)
+    {
+      if (fail)
+      {
+        throw new CacheException("could not unmarshall cache configuration",
+          ex);
+      }
+      else
+      {
+        logger.warn("could not unmarshall cache configuration", ex);
+      }
+    }
+
+    return config;
+  }
+
+  //~--- fields ---------------------------------------------------------------
+
+  /** Field description */
+  private JAXBContext context;
+}