merge with branch issue-395

scm-webapp/src/main/java/sonia/scm/plugin/Aether.java

@@ -0,0 +1,214 @@
+/**
+ * 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.plugin;
+
+//~--- non-JDK imports --------------------------------------------------------
+
+import org.apache.maven.repository.internal.MavenRepositorySystemSession;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import org.sonatype.aether.RepositorySystem;
+import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.collection.CollectRequest;
+import org.sonatype.aether.collection.DependencyCollectionException;
+import org.sonatype.aether.graph.Dependency;
+import org.sonatype.aether.graph.DependencyFilter;
+import org.sonatype.aether.graph.DependencyNode;
+import org.sonatype.aether.repository.LocalRepository;
+import org.sonatype.aether.repository.LocalRepositoryManager;
+import org.sonatype.aether.repository.Proxy;
+import org.sonatype.aether.repository.RemoteRepository;
+import org.sonatype.aether.repository.RepositoryPolicy;
+import org.sonatype.aether.resolution.DependencyRequest;
+import org.sonatype.aether.resolution.DependencyResolutionException;
+import org.sonatype.aether.util.artifact.DefaultArtifact;
+import org.sonatype.aether.util.artifact.JavaScopes;
+import org.sonatype.aether.util.filter.DependencyFilterUtils;
+
+import sonia.scm.config.ScmConfiguration;
+import sonia.scm.net.Proxies;
+
+/**
+ *
+ * @author Sebastian Sdorra
+ */
+public final class Aether
+{
+
+  /** Field description */
+  private static final DependencyFilter FILTER = new AetherDependencyFilter();
+
+  /**
+   * the logger for Aether
+   */
+  private static final Logger logger = LoggerFactory.getLogger(Aether.class);
+
+  //~--- constructors ---------------------------------------------------------
+
+  /**
+   * Constructs ...
+   *
+   */
+  private Aether() {}
+
+  //~--- methods --------------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @param gav
+   *
+   * @return
+   */
+  public static Dependency createDependency(String gav)
+  {
+    return new Dependency(new DefaultArtifact(gav), JavaScopes.RUNTIME);
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  public static DependencyFilter createDependencyFilter()
+  {
+    return DependencyFilterUtils.andFilter(
+      DependencyFilterUtils.classpathFilter(JavaScopes.RUNTIME), FILTER);
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param configuration
+   * @param pluginRepository
+   *
+   * @return
+   */
+  public static RemoteRepository createRemoteRepository(
+    ScmConfiguration configuration, PluginRepository pluginRepository)
+  {
+    RemoteRepository remoteRepository =
+      new RemoteRepository(pluginRepository.getId(), "default",
+        pluginRepository.getUrl());
+
+    if (Proxies.isEnabled(configuration, remoteRepository.getHost()))
+    {
+      Proxy proxy = DefaultProxySelector.createProxy(configuration);
+
+      if (logger.isDebugEnabled())
+      {
+        logger.debug("enable proxy {} for {}", proxy.getHost(),
+          pluginRepository.getUrl());
+      }
+
+      remoteRepository.setProxy(proxy);
+    }
+
+    return remoteRepository;
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  public static RepositorySystem createRepositorySystem()
+  {
+    return new AetherServiceLocator().getService(RepositorySystem.class);
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param system
+   * @param repositoryManager
+   * @param localRepository
+   * @param configuration
+   *
+   * @return
+   */
+  public static RepositorySystemSession createRepositorySystemSession(
+    RepositorySystem system, LocalRepository localRepository,
+    ScmConfiguration configuration)
+  {
+    MavenRepositorySystemSession session = new MavenRepositorySystemSession();
+
+    session.setChecksumPolicy(RepositoryPolicy.CHECKSUM_POLICY_WARN);
+
+    if (configuration.isEnableProxy())
+    {
+        logger.debug("enable proxy selector to collect dependencies");
+      session.setProxySelector(new DefaultProxySelector(configuration));
+    }
+
+    LocalRepositoryManager localRepositoryManager =
+      system.newLocalRepositoryManager(localRepository);
+
+    session.setLocalRepositoryManager(localRepositoryManager);
+
+    return session;
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param system
+   * @param session
+   * @param request
+   *
+   *
+   * @return
+   * @throws DependencyCollectionException
+   * @throws DependencyResolutionException
+   */
+  public static DependencyNode resolveDependencies(RepositorySystem system,
+    RepositorySystemSession session, CollectRequest request)
+    throws DependencyCollectionException, DependencyResolutionException
+  {
+    DependencyNode node = system.collectDependencies(session,
+                            request).getRoot();
+    DependencyRequest dr = new DependencyRequest(node,
+                             Aether.createDependencyFilter());
+
+    system.resolveDependencies(session, dr);
+
+    return node;
+  }
+}

scm-webapp/src/main/java/sonia/scm/plugin/AetherDependencyResolver.java

@@ -0,0 +1,210 @@
+/**
+ * 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.plugin;
+
+//~--- non-JDK imports --------------------------------------------------------
+
+import com.google.common.collect.Lists;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import org.sonatype.aether.RepositorySystem;
+import org.sonatype.aether.RepositorySystemSession;
+import org.sonatype.aether.collection.CollectRequest;
+import org.sonatype.aether.collection.DependencyCollectionException;
+import org.sonatype.aether.graph.Dependency;
+import org.sonatype.aether.graph.DependencyNode;
+import org.sonatype.aether.repository.LocalRepository;
+import org.sonatype.aether.repository.RemoteRepository;
+import org.sonatype.aether.resolution.DependencyResolutionException;
+import org.sonatype.aether.util.graph.PreorderNodeListGenerator;
+
+import sonia.scm.config.ScmConfiguration;
+
+//~--- JDK imports ------------------------------------------------------------
+
+import java.util.List;
+
+/**
+ *
+ * @author Sebastian Sdorra
+ */
+public class AetherDependencyResolver
+{
+
+  /**
+   * the logger for AetherDependencyResolver
+   */
+  private static final Logger logger =
+    LoggerFactory.getLogger(AetherDependencyResolver.class);
+
+  //~--- constructors ---------------------------------------------------------
+
+  /**
+   * Constructs ...
+   *
+   *
+   * @param configuration
+   * @param system
+   * @param localRepository
+   * @param remoteRepositories
+   */
+  public AetherDependencyResolver(ScmConfiguration configuration,
+    RepositorySystem system, LocalRepository localRepository,
+    List<RemoteRepository> remoteRepositories)
+  {
+    this.configuration = configuration;
+    this.system = system;
+    this.localRepository = localRepository;
+    this.remoteRepositories = remoteRepositories;
+  }
+
+  //~--- methods --------------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  public String createClassPath()
+  {
+    PreorderNodeListGenerator nodeListGenerator =
+      new PreorderNodeListGenerator();
+
+    for (DependencyNode node : resolvedNodes)
+    {
+      node.accept(nodeListGenerator);
+    }
+
+    return nodeListGenerator.getClassPath();
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param dependency
+   *
+   * @throws DependencyCollectionException
+   * @throws DependencyResolutionException
+   */
+  public void resolveLocalDependency(Dependency dependency)
+    throws DependencyCollectionException, DependencyResolutionException
+  {
+    CollectRequest request = new CollectRequest();
+
+    request.setRoot(dependency);
+    resolveDependency(request);
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param dependency
+   *
+   * @throws DependencyCollectionException
+   * @throws DependencyResolutionException
+   */
+  public void resolveRemoteDependency(Dependency dependency)
+    throws DependencyCollectionException, DependencyResolutionException
+  {
+    resolveDependency(new CollectRequest(dependency, remoteRepositories));
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param request
+   *
+   * @throws DependencyCollectionException
+   * @throws DependencyResolutionException
+   */
+  private void resolveDependency(CollectRequest request)
+    throws DependencyCollectionException, DependencyResolutionException
+  {
+    DependencyNode node = Aether.resolveDependencies(system, getSession(),
+                            request);
+
+    if (logger.isTraceEnabled())
+    {
+      StringDependencyGraphDumper dumper = new StringDependencyGraphDumper();
+
+      node.accept(dumper);
+      logger.trace(dumper.getGraphAsString());
+    }
+
+    resolvedNodes.add(node);
+  }
+
+  //~--- get methods ----------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  private RepositorySystemSession getSession()
+  {
+    if (session == null)
+    {
+      session = Aether.createRepositorySystemSession(system, localRepository,
+        configuration);
+    }
+
+    return session;
+  }
+
+  //~--- fields ---------------------------------------------------------------
+
+  /** Field description */
+  private ScmConfiguration configuration;
+
+  /** Field description */
+  private LocalRepository localRepository;
+
+  /** Field description */
+  private List<RemoteRepository> remoteRepositories;
+
+  /** Field description */
+  private List<DependencyNode> resolvedNodes = Lists.newArrayList();
+
+  /** Field description */
+  private RepositorySystemSession session;
+
+  /** Field description */
+  private RepositorySystem system;
+}

scm-webapp/src/main/java/sonia/scm/plugin/AetherPluginHandler.java

@@ -35,32 +35,21 @@ package sonia.scm.plugin;
 
 //~--- non-JDK imports --------------------------------------------------------
 
-import org.apache.maven.repository.internal.MavenRepositorySystemSession;
+import com.google.common.collect.Lists;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import org.sonatype.aether.RepositorySystem;
-import org.sonatype.aether.collection.CollectRequest;
 import org.sonatype.aether.graph.Dependency;
-import org.sonatype.aether.graph.DependencyFilter;
-import org.sonatype.aether.graph.DependencyNode;
-import org.sonatype.aether.repository.LocalArtifactRegistration;
 import org.sonatype.aether.repository.LocalRepository;
-import org.sonatype.aether.repository.LocalRepositoryManager;
-import org.sonatype.aether.repository.Proxy;
 import org.sonatype.aether.repository.RemoteRepository;
-import org.sonatype.aether.repository.RepositoryPolicy;
-import org.sonatype.aether.resolution.DependencyRequest;
-import org.sonatype.aether.util.artifact.DefaultArtifact;
-import org.sonatype.aether.util.graph.PreorderNodeListGenerator;
 
 import sonia.scm.ConfigurationException;
 import sonia.scm.SCMContextProvider;
 import sonia.scm.boot.BootstrapListener;
 import sonia.scm.boot.Classpath;
 import sonia.scm.config.ScmConfiguration;
-import sonia.scm.net.Proxies;
 import sonia.scm.util.IOUtil;
 import sonia.scm.util.Util;
 
@@ -68,7 +57,6 @@ import sonia.scm.util.Util;
 
 import java.io.File;
 
-import java.util.ArrayList;
 import java.util.Collection;
 import java.util.LinkedHashSet;
 import java.util.List;
@@ -85,15 +73,12 @@ import javax.xml.bind.Marshaller;
 public class AetherPluginHandler
 {
 
-  /** Field description */
-  public static final String PLUGIN_SCOPE = "runtime";
-
   /** the logger for AetherPluginHandler */
   private static final Logger logger =
     LoggerFactory.getLogger(AetherPluginHandler.class);
 
   /** Field description */
-  private static final DependencyFilter FILTER = new AetherDependencyFilter();
+  private static final Object LOCK = new Object();
 
   //~--- constructors ---------------------------------------------------------
 
@@ -120,7 +105,8 @@ public class AetherPluginHandler
     }
     catch (JAXBException ex)
     {
-      throw new ConfigurationException(ex);
+      throw new ConfigurationException(
+        "could not create jaxb context for classpath file", ex);
     }
 
     classpathFile = new File(localRepositoryDirectory,
@@ -135,12 +121,12 @@ public class AetherPluginHandler
       }
       catch (JAXBException ex)
       {
-        logger.error(ex.getMessage(), ex);
+        logger.error("could not read classpath file", ex);
       }
     }
 
     IOUtil.mkdirs(localRepositoryDirectory);
-    repositorySystem = createRepositorySystem();
+    repositorySystem = Aether.createRepositorySystem();
     localRepository = new LocalRepository(localRepositoryDirectory);
   }
 
@@ -154,16 +140,10 @@ public class AetherPluginHandler
    */
   public void install(String gav)
   {
-    if (logger.isInfoEnabled())
+    synchronized (LOCK)
     {
-      logger.info("try to install plugin with gav: {}", gav);
+      doInstall(gav);
     }
-
-    Dependency dependency = new Dependency(new DefaultArtifact(gav),
-                              PLUGIN_SCOPE);
-    List<Dependency> dependencies = getInstalledDependencies(null);
-
-    collectDependencies(dependency, dependencies);
   }
 
   /**
@@ -175,19 +155,9 @@ public class AetherPluginHandler
    */
   public void uninstall(String id)
   {
-    if (logger.isInfoEnabled())
+    synchronized (LOCK)
     {
-      logger.info("try to uninstall plugin: {}", id);
+      doUninstall(id);
-    }
-
-    if (classpath != null)
-    {
-      synchronized (Classpath.class)
-      {
-        List<Dependency> dependencies = getInstalledDependencies(id);
-
-        collectDependencies(null, dependencies);
-      }
     }
   }
 
@@ -201,27 +171,12 @@ public class AetherPluginHandler
    */
   public void setPluginRepositories(Collection<PluginRepository> repositories)
   {
-    remoteRepositories = new ArrayList<RemoteRepository>();
+    remoteRepositories = Lists.newArrayList();
 
     for (PluginRepository repository : repositories)
     {
-      RemoteRepository rr = new RemoteRepository(repository.getId(), "default",
+      remoteRepositories.add(Aether.createRemoteRepository(configuration,
-                              repository.getUrl());
+        repository));
-
-      if (Proxies.isEnabled(configuration, rr.getHost()))
-      {
-        Proxy proxy = DefaultProxySelector.createProxy(configuration);
-
-        if (logger.isDebugEnabled())
-        {
-          logger.debug("enable proxy {} for {}", proxy.getHost(),
-            repository.getUrl());
-        }
-
-        rr.setProxy(proxy);
-      }
-
-      remoteRepositories.add(rr);
     }
   }
 
@@ -233,68 +188,38 @@ public class AetherPluginHandler
    *
    * @param dependency
    * @param dependencies
+   * @param localDependencies
    */
   private void collectDependencies(Dependency dependency,
-    List<Dependency> dependencies)
+    List<Dependency> localDependencies)
   {
-    CollectRequest request = new CollectRequest(dependency, dependencies,
-                               remoteRepositories);
-    MavenRepositorySystemSession session = new MavenRepositorySystemSession();
-
-    session.setChecksumPolicy(RepositoryPolicy.CHECKSUM_POLICY_WARN);
-
-    if (configuration.isEnableProxy())
-    {
-      if (logger.isDebugEnabled())
-      {
-        logger.debug("enable proxy selector to collect dependencies");
-      }
-
-      session.setProxySelector(new DefaultProxySelector(configuration));
-    }
-
-    // register installed to local repository manager
-    LocalRepositoryManager localRepositoryManager =
-      repositorySystem.newLocalRepositoryManager(localRepository);
-
-    for (Dependency dep : dependencies)
-    {
-      localRepositoryManager.add(session,
-        new LocalArtifactRegistration(dep.getArtifact()));
-    }
-
-    session.setLocalRepositoryManager(localRepositoryManager);
-
     try
     {
-      DependencyNode node = repositorySystem.collectDependencies(session,
+      AetherDependencyResolver resolver =
-                              request).getRoot();
+        new AetherDependencyResolver(configuration, repositorySystem,
-      DependencyRequest dr = new DependencyRequest(node, FILTER);
+          localRepository, remoteRepositories);
 
-      repositorySystem.resolveDependencies(session, dr);
+      resolver.resolveRemoteDependency(dependency);
 
-      synchronized (Classpath.class)
+      for (Dependency localDependency : localDependencies)
       {
+        resolver.resolveLocalDependency(localDependency);
+      }
+
       if (classpath == null)
       {
         classpath = new Classpath();
       }
 
-        PreorderNodeListGenerator nodeListGenerator =
+      Set<String> classpathSet = createClasspathSet(resolver.createClassPath());
-          new PreorderNodeListGenerator();
-
-        node.accept(nodeListGenerator);
-
-        Set<String> classpathSet =
-          createClasspathSet(nodeListGenerator.getClassPath());
 
       classpath.setPathSet(classpathSet);
       storeClasspath();
     }
-    }
     catch (Exception ex)
     {
-      throw new PluginException(ex);
+      throw new PluginException(
+        "could not collect dependencies or store classpath file", ex);
     }
   }
 
@@ -333,11 +258,40 @@ public class AetherPluginHandler
    * Method description
    *
    *
-   * @return
+   * @param gav
    */
-  private RepositorySystem createRepositorySystem()
+  private void doInstall(String gav)
   {
-    return new AetherServiceLocator().getService(RepositorySystem.class);
+    if (logger.isInfoEnabled())
+    {
+      logger.info("try to install plugin with gav: {}", gav);
+    }
+
+    Dependency dependency = Aether.createDependency(gav);
+    List<Dependency> dependencies = getInstalledDependencies(null);
+
+    collectDependencies(dependency, dependencies);
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param id
+   */
+  private void doUninstall(String id)
+  {
+    if (logger.isInfoEnabled())
+    {
+      logger.info("try to uninstall plugin: {}", id);
+    }
+
+    if (classpath != null)
+    {
+      List<Dependency> dependencies = getInstalledDependencies(id);
+
+      collectDependencies(null, dependencies);
+    }
   }
 
   /**
@@ -366,7 +320,7 @@ public class AetherPluginHandler
    */
   private List<Dependency> getInstalledDependencies(String skipId)
   {
-    List<Dependency> dependencies = new ArrayList<Dependency>();
+    List<Dependency> dependencies = Lists.newArrayList();
     Collection<PluginInformation> installed =
       pluginManager.get(new StatePluginFilter(PluginState.INSTALLED));
 
@@ -378,8 +332,7 @@ public class AetherPluginHandler
 
         if (Util.isNotEmpty(id) && ((skipId == null) ||!id.equals(skipId)))
         {
-          dependencies.add(new Dependency(new DefaultArtifact(id),
+          dependencies.add(Aether.createDependency(id));
-            PLUGIN_SCOPE));
         }
       }
     }

scm-webapp/src/main/java/sonia/scm/plugin/StringDependencyGraphDumper.java

@@ -0,0 +1,121 @@
+/**
+ * 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.plugin;
+
+//~--- non-JDK imports --------------------------------------------------------
+
+import org.sonatype.aether.graph.DependencyNode;
+import org.sonatype.aether.graph.DependencyVisitor;
+
+/**
+ *
+ * @author Sebastian Sdorra
+ */
+public class StringDependencyGraphDumper implements DependencyVisitor
+{
+
+  /** Field description */
+  private static final String LINE_SEPARATOR = System.getProperty("line.separator");
+
+  //~--- methods --------------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   */
+  public void reset()
+  {
+    buffer = new StringBuilder();
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param node
+   *
+   * @return
+   */
+  @Override
+  public boolean visitEnter(DependencyNode node)
+  {
+    buffer.append(currentIndent).append(node).append(LINE_SEPARATOR);
+
+    if (currentIndent.length() <= 0)
+    {
+      currentIndent = "+- ";
+    }
+    else
+    {
+      currentIndent = "|  " + currentIndent;
+    }
+
+    return true;
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @param node
+   *
+   * @return
+   */
+  @Override
+  public boolean visitLeave(DependencyNode node)
+  {
+    currentIndent = currentIndent.substring(3, currentIndent.length());
+
+    return true;
+  }
+
+  //~--- get methods ----------------------------------------------------------
+
+  /**
+   * Method description
+   *
+   *
+   * @return
+   */
+  public String getGraphAsString()
+  {
+    return buffer.toString();
+  }
+
+  //~--- fields ---------------------------------------------------------------
+
+  /** Field description */
+  private StringBuilder buffer = new StringBuilder();
+
+  /** Field description */
+  private String currentIndent = "";
+}