merge

scm-core/src/main/java/sonia/scm/AlreadyExistsException.java

@@ -1,11 +1,34 @@
 package sonia.scm;
 
-public class AlreadyExistsException extends Exception {
+import java.util.List;
 
-  public AlreadyExistsException(String message) {
-    super(message);
+import static java.util.Collections.singletonList;
+import static java.util.stream.Collectors.joining;
+
+public class AlreadyExistsException extends ExceptionWithContext {
+
+  private static final String CODE = "FtR7UznKU1";
+
+  public AlreadyExistsException(ModelObject object) {
+    this(singletonList(new ContextEntry(object.getClass(), object.getId())));
   }
 
-  public AlreadyExistsException() {
+  public static AlreadyExistsException alreadyExists(ContextEntry.ContextBuilder builder) {
+    return new AlreadyExistsException(builder.build());
+  }
+
+  private AlreadyExistsException(List<ContextEntry> context) {
+    super(context, createMessage(context));
+  }
+
+  @Override
+  public String getCode() {
+    return CODE;
+  }
+
+  private static String createMessage(List<ContextEntry> context) {
+    return context.stream()
+      .map(c -> c.getType().toLowerCase() + " with id " + c.getId())
+      .collect(joining(" in ", "", " already exists"));
   }
 }

scm-core/src/main/java/sonia/scm/ConcurrentModificationException.java

@@ -1,4 +1,34 @@
 package sonia.scm;
 
-public class ConcurrentModificationException extends Exception {
+import java.util.Collections;
+import java.util.List;
+
+import static java.util.stream.Collectors.joining;
+
+public class ConcurrentModificationException extends ExceptionWithContext {
+
+  private static final String CODE = "2wR7UzpPG1";
+
+  public ConcurrentModificationException(Class type, String id) {
+    this(Collections.singletonList(new ContextEntry(type, id)));
+  }
+
+  public ConcurrentModificationException(String type, String id) {
+    this(Collections.singletonList(new ContextEntry(type, id)));
+  }
+
+  private ConcurrentModificationException(List<ContextEntry> context) {
+    super(context, createMessage(context));
+  }
+
+  @Override
+  public String getCode() {
+    return CODE;
+  }
+
+  private static String createMessage(List<ContextEntry> context) {
+    return context.stream()
+      .map(c -> c.getType().toLowerCase() + " with id " + c.getId())
+      .collect(joining(" in ", "", " has been modified concurrently"));
+  }
 }

scm-core/src/main/java/sonia/scm/ContextEntry.java

@@ -0,0 +1,84 @@
+package sonia.scm;
+
+import sonia.scm.repository.NamespaceAndName;
+import sonia.scm.repository.Repository;
+import sonia.scm.util.AssertUtil;
+
+import java.util.Collections;
+import java.util.LinkedList;
+import java.util.List;
+
+public class ContextEntry {
+  private final String type;
+  private final String id;
+
+  ContextEntry(Class type, String id) {
+    this(type.getSimpleName(), id);
+  }
+
+  ContextEntry(String type, String id) {
+    AssertUtil.assertIsNotEmpty(type);
+    AssertUtil.assertIsNotEmpty(id);
+    this.type = type;
+    this.id = id;
+  }
+
+  public String getType() {
+    return type;
+  }
+
+  public String getId() {
+    return id;
+  }
+
+
+  public static class ContextBuilder {
+    private final List<ContextEntry> context = new LinkedList<>();
+
+    public static List<ContextEntry> noContext() {
+      return new ContextBuilder().build();
+    }
+
+    public static List<ContextEntry> only(String type, String id) {
+      return new ContextBuilder().in(type, id).build();
+    }
+
+    public static ContextBuilder entity(Repository repository) {
+      return new ContextBuilder().in(repository.getNamespaceAndName());
+    }
+
+    public static ContextBuilder entity(NamespaceAndName namespaceAndName) {
+      return new ContextBuilder().in(Repository.class, namespaceAndName.logString());
+    }
+
+    public static ContextBuilder entity(Class type, String id) {
+      return new ContextBuilder().in(type, id);
+    }
+
+    public static ContextBuilder entity(String type, String id) {
+      return new ContextBuilder().in(type, id);
+    }
+
+    public ContextBuilder in(Repository repository) {
+      return in(repository.getNamespaceAndName());
+    }
+
+    public ContextBuilder in(NamespaceAndName namespaceAndName) {
+      return this.in(Repository.class, namespaceAndName.logString());
+    }
+
+    public ContextBuilder in(Class type, String id) {
+      context.add(new ContextEntry(type, id));
+      return this;
+    }
+
+    public ContextBuilder in(String type, String id) {
+      context.add(new ContextEntry(type, id));
+      return this;
+    }
+
+    public List<ContextEntry> build() {
+      return Collections.unmodifiableList(context);
+    }
+  }
+}

scm-core/src/main/java/sonia/scm/ExceptionWithContext.java

@@ -0,0 +1,26 @@
+package sonia.scm;
+
+import java.util.List;
+
+import static java.util.Collections.unmodifiableList;
+
+public abstract class ExceptionWithContext extends RuntimeException {
+
+  private final List<ContextEntry> context;
+
+  public ExceptionWithContext(List<ContextEntry> context, String message) {
+    super(message);
+    this.context = context;
+  }
+
+  public ExceptionWithContext(List<ContextEntry> context, String message, Exception cause) {
+    super(message, cause);
+    this.context = context;
+  }
+
+  public List<ContextEntry> getContext() {
+    return unmodifiableList(context);
+  }
+
+  public abstract String getCode();
+}

scm-core/src/main/java/sonia/scm/HandlerBase.java

@@ -54,25 +54,21 @@ public interface HandlerBase<T extends TypedObject>
    *
    * @return  The persisted object.
    */
-  T create(T object) throws AlreadyExistsException;
+  T create(T object);
 
   /**
    * Removes a persistent object.
    *
    *
    * @param object to delete
-   *
-   * @throws IOException
    */
-  void delete(T object) throws NotFoundException;
+  void delete(T object);
 
   /**
    * Modifies a persistent object.
    *
    *
    * @param object to modify
-   *
-   * @throws IOException
    */
-  void modify(T object) throws NotFoundException;
+  void modify(T object);
 }

scm-core/src/main/java/sonia/scm/Manager.java

@@ -58,7 +58,7 @@ public interface Manager<T extends ModelObject>
    *
    * @throws NotFoundException
    */
-  void refresh(T object) throws NotFoundException;
+  void refresh(T object);
 
   //~--- get methods ----------------------------------------------------------
 

scm-core/src/main/java/sonia/scm/ManagerDecorator.java

@@ -66,7 +66,7 @@ public class ManagerDecorator<T extends ModelObject> implements Manager<T> {
   }
 
   @Override
-  public T create(T object) throws AlreadyExistsException {
+  public T create(T object) {
     return decorated.create(object);
   }
 

scm-core/src/main/java/sonia/scm/NotFoundException.java

@@ -1,10 +1,38 @@
 package sonia.scm;
 
-public class NotFoundException extends RuntimeException {
-  public NotFoundException(String type, String id) {
-    super(type + " with id '" + id + "' not found");
+import java.util.Collections;
+import java.util.List;
+
+import static java.util.stream.Collectors.joining;
+
+public class NotFoundException extends ExceptionWithContext {
+
+  private static final String CODE = "AGR7UzkhA1";
+
+  public NotFoundException(Class type, String id) {
+    this(Collections.singletonList(new ContextEntry(type, id)));
   }
 
-  public NotFoundException() {
+  public NotFoundException(String type, String id) {
+    this(Collections.singletonList(new ContextEntry(type, id)));
+  }
+
+  public static NotFoundException notFound(ContextEntry.ContextBuilder contextBuilder) {
+    return new NotFoundException(contextBuilder.build());
+  }
+
+  private NotFoundException(List<ContextEntry> context) {
+    super(context, createMessage(context));
+  }
+
+  @Override
+  public String getCode() {
+    return CODE;
+  }
+
+  private static String createMessage(List<ContextEntry> context) {
+    return context.stream()
+      .map(c -> c.getType().toLowerCase() + " with id " + c.getId())
+      .collect(joining(" in ", "could not find ", ""));
   }
 }

scm-core/src/main/java/sonia/scm/NotSupportedFeatureException.java

@@ -33,33 +33,30 @@
 
 package sonia.scm;
 
+import java.util.Collections;
+
 /**
  *
  * @author Sebastian Sdorra
  * @version 1.6
  */
-public class NotSupportedFeatuerException extends Exception
-{
+public class NotSupportedFeatureException extends ExceptionWithContext {
 
-  /** Field description */
   private static final long serialVersionUID = 256498734456613496L;
 
-  //~--- constructors ---------------------------------------------------------
+  private static final String CODE = "9SR8G0kmU1";
 
-  /**
-   * Constructs ...
-   *
-   */
-  public NotSupportedFeatuerException() {}
-
-  /**
-   * Constructs ...
-   *
-   *
-   * @param message
-   */
-  public NotSupportedFeatuerException(String message)
+  public NotSupportedFeatureException(String feature)
   {
-    super(message);
+    super(Collections.emptyList(),createMessage(feature));
+  }
+
+  @Override
+  public String getCode() {
+    return CODE;
+  }
+
+  private static String createMessage(String feature) {
+    return "feature " + feature + " is not supported by this repository";
   }
 }

scm-core/src/main/java/sonia/scm/filter/Filters.java

@@ -45,28 +45,12 @@ public final class Filters
   /** Field description */
   public static final String PATTERN_ALL = "/*";
 
-  /** Field description */
-  public static final String PATTERN_CONFIG = REST_API_PATH + "/config*";
-
   /** Field description */
   public static final String PATTERN_DEBUG = "/debug.html";
 
-  /** Field description */
-  public static final String PATTERN_GROUPS = REST_API_PATH + "/groups*";
-
-  /** Field description */
-  public static final String PATTERN_PLUGINS = REST_API_PATH + "/plugins*";
-
-  /** Field description */
-  public static final String PATTERN_RESOURCE_REGEX =
-    "^/(?:resources|api|plugins|index)[\\./].*(?:html|\\.css|\\.js|\\.xml|\\.json|\\.txt)";
-
   /** Field description */
   public static final String PATTERN_RESTAPI = REST_API_PATH + "/*";
 
-  /** Field description */
-  public static final String PATTERN_USERS = REST_API_PATH + "/users*";
-
   /** authentication priority */
   public static final int PRIORITY_AUTHENTICATION = 5000;
 

scm-core/src/main/java/sonia/scm/repository/AbstractRepositoryHandler.java

@@ -38,7 +38,7 @@ package sonia.scm.repository;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import sonia.scm.NotSupportedFeatuerException;
+import sonia.scm.NotSupportedFeatureException;
 import sonia.scm.SCMContextProvider;
 import sonia.scm.event.ScmEventBus;
 
@@ -165,13 +165,12 @@ public abstract class AbstractRepositoryHandler<C extends RepositoryConfig>
    *
    * @return
    *
-   * @throws NotSupportedFeatuerException
+   * @throws NotSupportedFeatureException
    */
   @Override
-  public ImportHandler getImportHandler() throws NotSupportedFeatuerException
+  public ImportHandler getImportHandler() throws NotSupportedFeatureException
   {
-    throw new NotSupportedFeatuerException(
-      "import handler is not supported by this repository handler");
+    throw new NotSupportedFeatureException("import");
   }
 
   /**

scm-core/src/main/java/sonia/scm/repository/AbstractSimpleRepositoryHandler.java

@@ -40,6 +40,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import sonia.scm.AlreadyExistsException;
 import sonia.scm.ConfigurationException;
+import sonia.scm.ContextEntry;
 import sonia.scm.io.CommandResult;
 import sonia.scm.io.ExtendedCommand;
 import sonia.scm.io.FileSystem;
@@ -80,13 +81,13 @@ public abstract class AbstractSimpleRepositoryHandler<C extends RepositoryConfig
   }
 
   @Override
-  public Repository create(Repository repository) throws AlreadyExistsException {
+  public Repository create(Repository repository) {
     File directory = repositoryLocationResolver.getInitialNativeDirectory(repository);
     if (directory != null && directory.exists()) {
-      throw new AlreadyExistsException();
+      throw new AlreadyExistsException(repository);
     }
 
-    checkPath(directory);
+    checkPath(directory, repository);
 
     try {
       fileSystem.create(directory);
@@ -120,15 +121,20 @@ public abstract class AbstractSimpleRepositoryHandler<C extends RepositoryConfig
 
   @Override
   public void delete(Repository repository) {
+    File directory = null;
+    try {
+      directory = repositoryLocationResolver.getRepositoryDirectory(repository);
+    } catch (IOException e) {
+      throw new InternalRepositoryException(repository, "Cannot get the repository directory");
+    }
     try {
-      File directory = repositoryLocationResolver.getRepositoryDirectory(repository);
       if (directory.exists()) {
         fileSystem.destroy(directory);
       } else {
         logger.warn("repository {} not found", repository.getNamespaceAndName());
       }
     } catch (IOException e) {
-      throw new InternalRepositoryException("could not delete repository directory", e);
+      throw new InternalRepositoryException(ContextEntry.ContextBuilder.entity("directory", directory.toString()).in(repository), "could not delete repository directory", e);
     }
   }
 
@@ -178,7 +184,7 @@ public abstract class AbstractSimpleRepositoryHandler<C extends RepositoryConfig
   }
 
   protected void create(Repository repository, File directory)
-    throws IOException, AlreadyExistsException {
+    throws IOException {
     ExtendedCommand cmd = buildCreateCommand(repository, directory);
     CommandResult result = cmd.execute();
 
@@ -233,9 +239,9 @@ public abstract class AbstractSimpleRepositoryHandler<C extends RepositoryConfig
    * Check path for existing repositories
    *
    * @param directory repository target directory
-   * @throws AlreadyExistsException
+   * @throws RuntimeException when the parent directory already is a repository
    */
-  private void checkPath(File directory) throws AlreadyExistsException {
+  private void checkPath(File directory, Repository repository) {
     if (directory == null) {
       return;
     }
@@ -246,9 +252,7 @@ public abstract class AbstractSimpleRepositoryHandler<C extends RepositoryConfig
       logger.trace("check {} for existing repository", parent);
 
       if (isRepository(parent)) {
-        logger.error("parent path {} is a repository", parent);
-
-        throw new AlreadyExistsException();
+      throw new InternalRepositoryException(repository, "parent path" + parent + " is a repository");
       }
 
       parent = parent.getParentFile();

scm-core/src/main/java/sonia/scm/repository/InternalRepositoryException.java

@@ -1,15 +1,34 @@
 package sonia.scm.repository;
 
-public class InternalRepositoryException extends RuntimeException {
-  public InternalRepositoryException(Throwable ex) {
-    super(ex);
+import sonia.scm.ContextEntry;
+import sonia.scm.ExceptionWithContext;
+
+import java.util.List;
+
+public class InternalRepositoryException extends ExceptionWithContext {
+
+  public InternalRepositoryException(ContextEntry.ContextBuilder context, String message) {
+    this(context, message, null);
   }
 
-  public InternalRepositoryException(String msg, Exception ex) {
-    super(msg, ex);
+  public InternalRepositoryException(ContextEntry.ContextBuilder context, String message, Exception cause) {
+    this(context.build(), message, cause);
   }
 
-  public InternalRepositoryException(String message) {
-    super(message);
+  public InternalRepositoryException(Repository repository, String message) {
+    this(ContextEntry.ContextBuilder.entity(repository), message, null);
+  }
+
+  public InternalRepositoryException(Repository repository, String message, Exception cause) {
+    this(ContextEntry.ContextBuilder.entity(repository), message, cause);
+  }
+
+  public InternalRepositoryException(List<ContextEntry> context, String message, Exception cause) {
+    super(context, message, cause);
+  }
+
+  @Override
+  public String getCode() {
+    return null;
   }
 }

scm-core/src/main/java/sonia/scm/repository/NamespaceAndName.java

@@ -25,9 +25,13 @@ public class NamespaceAndName implements Comparable<NamespaceAndName> {
     return name;
   }
 
+  public String logString() {
+    return getNamespace() + "/" + getName();
+  }
+
   @Override
   public String toString() {
-    return getNamespace() + "/" + getName();
+    return logString();
   }
 
   @Override

scm-core/src/main/java/sonia/scm/repository/PathNotFoundException.java

@@ -1,84 +0,0 @@
-/**
- * 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.repository;
-
-//~--- non-JDK imports --------------------------------------------------------
-
-import sonia.scm.NotFoundException;
-import sonia.scm.util.Util;
-
-/**
- * Signals that the specified path could be found.
- *
- * @author Sebastian Sdorra
- */
-public class PathNotFoundException extends NotFoundException
-{
-
-  /** Field description */
-  private static final long serialVersionUID = 4629690181172951809L;
-
-  //~--- constructors ---------------------------------------------------------
-
-  /**
-   * Constructs a new {@link PathNotFoundException} 
-   * with the specified path.
-   *
-   *
-   * @param path path which could not be found
-   */
-  public PathNotFoundException(String path)
-  {
-    super("path", Util.nonNull(path));
-    this.path = Util.nonNull(path);
-  }
-
-  //~--- get methods ----------------------------------------------------------
-
-  /**
-   * Return the path which could not be found.
-   *
-   *
-   * @return path which could not be found
-   */
-  public String getPath()
-  {
-    return path;
-  }
-
-  //~--- fields ---------------------------------------------------------------
-
-  /** Field description */
-  private String path;
-}

scm-core/src/main/java/sonia/scm/repository/Repository.java

@@ -37,7 +37,6 @@ import com.github.sdorra.ssp.PermissionObject;
 import com.github.sdorra.ssp.StaticPermissions;
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Objects;
-import com.google.common.collect.Lists;
 import sonia.scm.BasicPropertiesAware;
 import sonia.scm.ModelObject;
 import sonia.scm.util.Util;
@@ -50,8 +49,11 @@ import javax.xml.bind.annotation.XmlElementWrapper;
 import javax.xml.bind.annotation.XmlRootElement;
 import javax.xml.bind.annotation.XmlTransient;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
 /**
  * Source code repository.
@@ -79,7 +81,7 @@ public class Repository extends BasicPropertiesAware implements ModelObject, Per
   private Long lastModified;
   private String namespace;
   private String name;
-  private List<Permission> permissions;
+  private final Set<Permission> permissions = new HashSet<>();
   @XmlElement(name = "public")
   private boolean publicReadable = false;
   private boolean archived = false;
@@ -127,7 +129,6 @@ public class Repository extends BasicPropertiesAware implements ModelObject, Per
     this.name = name;
     this.contact = contact;
     this.description = description;
-    this.permissions = Lists.newArrayList();
 
     if (Util.isNotEmpty(permissions)) {
       this.permissions.addAll(Arrays.asList(permissions));
@@ -200,12 +201,8 @@ public class Repository extends BasicPropertiesAware implements ModelObject, Per
     return new NamespaceAndName(getNamespace(), getName());
   }
 
-  public List<Permission> getPermissions() {
-    if (permissions == null) {
-      permissions = Lists.newArrayList();
-    }
-
-    return permissions;
+  public Collection<Permission> getPermissions() {
+    return Collections.unmodifiableCollection(permissions);
   }
 
   /**
@@ -300,8 +297,17 @@ public class Repository extends BasicPropertiesAware implements ModelObject, Per
     this.name = name;
   }
 
-  public void setPermissions(List<Permission> permissions) {
-    this.permissions = permissions;
+  public void setPermissions(Collection<Permission> permissions) {
+    this.permissions.clear();
+    this.permissions.addAll(permissions);
+  }
+
+  public void addPermission(Permission newPermission) {
+    this.permissions.add(newPermission);
+  }
+
+  public void removePermission(Permission permission) {
+    this.permissions.remove(permission);
   }
 
   public void setPublicReadable(boolean publicReadable) {

scm-core/src/main/java/sonia/scm/repository/RepositoryHandler.java

@@ -36,7 +36,7 @@ package sonia.scm.repository;
 //~--- non-JDK imports --------------------------------------------------------
 
 import sonia.scm.Handler;
-import sonia.scm.NotSupportedFeatuerException;
+import sonia.scm.NotSupportedFeatureException;
 import sonia.scm.plugin.ExtensionPoint;
 
 /**
@@ -70,9 +70,9 @@ public interface RepositoryHandler
    * @return {@link ImportHandler} for the repository type of this handler
    * @since 1.12
    *
-   * @throws NotSupportedFeatuerException
+   * @throws NotSupportedFeatureException
    */
-  public ImportHandler getImportHandler() throws NotSupportedFeatuerException;
+  public ImportHandler getImportHandler() throws NotSupportedFeatureException;
 
   /**
    * Returns informations about the version of the RepositoryHandler.

scm-core/src/main/java/sonia/scm/repository/RepositoryManager.java

@@ -35,7 +35,6 @@ package sonia.scm.repository;
 
 //~--- non-JDK imports --------------------------------------------------------
 
-import sonia.scm.AlreadyExistsException;
 import sonia.scm.TypeManager;
 
 import java.io.IOException;
@@ -73,7 +72,7 @@ public interface RepositoryManager
    *
    * @throws IOException
    */
-  public void importRepository(Repository repository) throws IOException, AlreadyExistsException;
+  public void importRepository(Repository repository) throws IOException;
 
   //~--- get methods ----------------------------------------------------------
 

scm-core/src/main/java/sonia/scm/repository/RepositoryManagerDecorator.java

@@ -35,7 +35,6 @@ package sonia.scm.repository;
 
 //~--- non-JDK imports --------------------------------------------------------
 
-import sonia.scm.AlreadyExistsException;
 import sonia.scm.ManagerDecorator;
 import sonia.scm.Type;
 
@@ -82,7 +81,7 @@ public class RepositoryManagerDecorator
    * {@inheritDoc}
    */
   @Override
-  public void importRepository(Repository repository) throws IOException, AlreadyExistsException {
+  public void importRepository(Repository repository) throws IOException {
     decorated.importRepository(repository);
   }
 

scm-core/src/main/java/sonia/scm/repository/RepositoryNotFoundException.java

@@ -1,68 +0,0 @@
-/**
- * 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.repository;
-
-import sonia.scm.NotFoundException;
-
-/**
- * Signals that the specified {@link Repository} could be found.
- *
- * @author Sebastian Sdorra
- * @since 1.6
- */
-public class RepositoryNotFoundException extends NotFoundException
-{
-
-  private static final long serialVersionUID = -6583078808900520166L;
-  private static final String TYPE_REPOSITORY = "repository";
-
-  //~--- constructors ---------------------------------------------------------
-
-  /**
-   * Constructs a new {@link RepositoryNotFoundException} with null as its 
-   * error detail message.
-   *
-   */
-  public RepositoryNotFoundException(Repository repository) {
-    super(TYPE_REPOSITORY, repository.getName() + "/"  + repository.getNamespace());
-  }
-
-  public RepositoryNotFoundException(String repositoryId) {
-    super(TYPE_REPOSITORY, repositoryId);
-  }
-
-  public RepositoryNotFoundException(NamespaceAndName namespaceAndName) {
-    super(TYPE_REPOSITORY, namespaceAndName.toString());
-  }
-}

scm-core/src/main/java/sonia/scm/repository/RevisionNotFoundException.java

@@ -1,83 +0,0 @@
-/**
- * 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.repository;
-
-//~--- non-JDK imports --------------------------------------------------------
-
-import sonia.scm.NotFoundException;
-import sonia.scm.util.Util;
-
-/**
- * Signals that the specified revision could be found.
- *
- * @author Sebastian Sdorra
- */
-public class RevisionNotFoundException extends NotFoundException {
-
-  /** Field description */
-  private static final long serialVersionUID = -5594008535358811998L;
-
-  //~--- constructors ---------------------------------------------------------
-
-  /**
-   * Constructs a new {@link RevisionNotFoundException} 
-   * with the specified revision.
-   *
-   *
-   * @param revision revision which could not be found
-   */
-  public RevisionNotFoundException(String revision)
-  {
-    super("revision", revision);
-    this.revision = Util.nonNull(revision);
-  }
-
-  //~--- get methods ----------------------------------------------------------
-
-  /**
-   * Return the revision which could not be found.
-   *
-   *
-   * @return revision which could not be found
-   */
-  public String getRevision()
-  {
-    return revision;
-  }
-
-  //~--- fields ---------------------------------------------------------------
-
-  /** Field description */
-  private String revision;
-}

scm-core/src/main/java/sonia/scm/repository/api/BrowseCommandBuilder.java

@@ -38,7 +38,6 @@ package sonia.scm.repository.api;
 import com.google.common.base.Objects;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import sonia.scm.NotFoundException;
 import sonia.scm.cache.Cache;
 import sonia.scm.cache.CacheManager;
 import sonia.scm.repository.BrowserResult;
@@ -46,7 +45,6 @@ import sonia.scm.repository.FileObject;
 import sonia.scm.repository.PreProcessorUtil;
 import sonia.scm.repository.Repository;
 import sonia.scm.repository.RepositoryCacheKey;
-import sonia.scm.repository.RevisionNotFoundException;
 import sonia.scm.repository.spi.BrowseCommand;
 import sonia.scm.repository.spi.BrowseCommandRequest;
 
@@ -136,7 +134,7 @@ public final class BrowseCommandBuilder
    *
    * @throws IOException
    */
-  public BrowserResult getBrowserResult() throws IOException, NotFoundException {
+  public BrowserResult getBrowserResult() throws IOException {
     BrowserResult result = null;
 
     if (disableCache)

scm-core/src/main/java/sonia/scm/repository/api/CatCommandBuilder.java

@@ -37,9 +37,7 @@ import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import sonia.scm.repository.PathNotFoundException;
 import sonia.scm.repository.Repository;
-import sonia.scm.repository.RevisionNotFoundException;
 import sonia.scm.repository.spi.CatCommand;
 import sonia.scm.repository.spi.CatCommandRequest;
 import sonia.scm.util.IOUtil;
@@ -107,7 +105,7 @@ public final class CatCommandBuilder
    * @param outputStream output stream for the content
    * @param path file path
    */
-  public void retriveContent(OutputStream outputStream, String path) throws IOException, PathNotFoundException, RevisionNotFoundException {
+  public void retriveContent(OutputStream outputStream, String path) throws IOException {
     getCatResult(outputStream, path);
   }
 
@@ -116,7 +114,7 @@ public final class CatCommandBuilder
    *
    * @param path file path
    */
-  public InputStream getStream(String path) throws IOException, PathNotFoundException, RevisionNotFoundException {
+  public InputStream getStream(String path) throws IOException {
     Preconditions.checkArgument(!Strings.isNullOrEmpty(path),
       "path is required");
 
@@ -139,7 +137,7 @@ public final class CatCommandBuilder
    *
    * @throws IOException
    */
-  public String getContent(String path) throws IOException, PathNotFoundException, RevisionNotFoundException {
+  public String getContent(String path) throws IOException {
     String content = null;
     ByteArrayOutputStream baos = null;
 
@@ -186,7 +184,7 @@ public final class CatCommandBuilder
    * @throws IOException
    */
   private void getCatResult(OutputStream outputStream, String path)
-    throws IOException, PathNotFoundException, RevisionNotFoundException {
+    throws IOException {
     Preconditions.checkNotNull(outputStream, "OutputStream is required");
     Preconditions.checkArgument(!Strings.isNullOrEmpty(path),
       "path is required");

scm-core/src/main/java/sonia/scm/repository/api/Command.java

@@ -66,6 +66,10 @@ public enum Command
   /**
    * @since 2.0
    */
-  MODIFICATIONS
+  MODIFICATIONS,
 
+  /**
+   * @since 2.0
+   */
+  MERGE
 }

scm-core/src/main/java/sonia/scm/repository/api/DiffCommandBuilder.java

@@ -38,7 +38,6 @@ package sonia.scm.repository.api;
 import com.google.common.base.Preconditions;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import sonia.scm.repository.RevisionNotFoundException;
 import sonia.scm.repository.spi.DiffCommand;
 import sonia.scm.repository.spi.DiffCommandRequest;
 import sonia.scm.util.IOUtil;
@@ -104,7 +103,7 @@ public final class DiffCommandBuilder
    *
    * @throws IOException
    */
-  public DiffCommandBuilder retriveContent(OutputStream outputStream) throws IOException, RevisionNotFoundException {
+  public DiffCommandBuilder retrieveContent(OutputStream outputStream) throws IOException {
     getDiffResult(outputStream);
 
     return this;
@@ -119,7 +118,7 @@ public final class DiffCommandBuilder
    *
    * @throws IOException
    */
-  public String getContent() throws IOException, RevisionNotFoundException {
+  public String getContent() throws IOException {
     String content = null;
     ByteArrayOutputStream baos = null;
 
@@ -199,7 +198,7 @@ public final class DiffCommandBuilder
    *
    * @throws IOException
    */
-  private void getDiffResult(OutputStream outputStream) throws IOException, RevisionNotFoundException {
+  private void getDiffResult(OutputStream outputStream) throws IOException {
     Preconditions.checkNotNull(outputStream, "OutputStream is required");
     Preconditions.checkArgument(request.isValid(),
       "path and/or revision is required");

scm-core/src/main/java/sonia/scm/repository/api/LogCommandBuilder.java

@@ -46,7 +46,6 @@ import sonia.scm.repository.ChangesetPagingResult;
 import sonia.scm.repository.PreProcessorUtil;
 import sonia.scm.repository.Repository;
 import sonia.scm.repository.RepositoryCacheKey;
-import sonia.scm.repository.RevisionNotFoundException;
 import sonia.scm.repository.spi.LogCommand;
 import sonia.scm.repository.spi.LogCommandRequest;
 
@@ -165,7 +164,7 @@ public final class LogCommandBuilder
    *
    * @throws IOException
    */
-  public Changeset getChangeset(String id) throws IOException, RevisionNotFoundException {
+  public Changeset getChangeset(String id) throws IOException {
     Changeset changeset;
 
     if (disableCache)
@@ -224,7 +223,7 @@ public final class LogCommandBuilder
    *
    * @throws IOException
    */
-  public ChangesetPagingResult getChangesets() throws IOException, RevisionNotFoundException {
+  public ChangesetPagingResult getChangesets() throws IOException {
     ChangesetPagingResult cpr;
 
     if (disableCache)
@@ -398,6 +397,11 @@ public final class LogCommandBuilder
     return this;
   }
 
+  public LogCommandBuilder setAncestorChangeset(String ancestorChangeset) {
+    request.setAncestorChangeset(ancestorChangeset);
+    return this;
+  }
+
   //~--- inner classes --------------------------------------------------------
 
   /**

scm-core/src/main/java/sonia/scm/repository/api/MergeCommandBuilder.java

@@ -0,0 +1,143 @@
+package sonia.scm.repository.api;
+
+import com.google.common.base.Preconditions;
+import sonia.scm.repository.Person;
+import sonia.scm.repository.spi.MergeCommand;
+import sonia.scm.repository.spi.MergeCommandRequest;
+
+/**
+ * Use this {@link MergeCommandBuilder} to merge two branches of a repository ({@link #executeMerge()}) or to check if
+ * the branches could be merged without conflicts ({@link #dryRun()}). To do so, you have to specify the name of
+ * the target branch ({@link #setTargetBranch(String)}) and the name of the branch that should be merged
+ * ({@link #setBranchToMerge(String)}). Additionally you can specify an author that should be used for the commit
+ * ({@link #setAuthor(Person)}) and a message template ({@link #setMessageTemplate(String)}) if you are not doing a dry
+ * run only. If no author is specified, the logged in user and a default message will be used instead.
+ *
+ * To actually merge <code>feature_branch</code> into <code>integration_branch</code> do this:
+ * <pre><code>
+ *     repositoryService.gerMergeCommand()
+ *       .setBranchToMerge("feature_branch")
+ *       .setTargetBranch("integration_branch")
+ *       .executeMerge();
+ * </code></pre>
+ *
+ * If the merge is successful, the result will look like this:
+ * <pre><code>
+ *                            O    <- Merge result (new head of integration_branch)
+ *                            |\
+ *                            | \
+ *  old integration_branch -> O  O <- feature_branch
+ *                            |  |
+ *                            O  O
+ * </code></pre>
+ *
+ * To check whether they can be merged without conflicts beforehand do this:
+ * <pre><code>
+ *     repositoryService.gerMergeCommand()
+ *       .setBranchToMerge("feature_branch")
+ *       .setTargetBranch("integration_branch")
+ *       .dryRun()
+ *       .isMergeable();
+ * </code></pre>
+ *
+ * Keep in mind that you should <em>always</em> check the result of a merge even though you may have done a dry run
+ * beforehand, because the branches can change between the dry run and the actual merge.
+ *
+ * @since 2.0.0
+ */
+public class MergeCommandBuilder {
+
+  private final MergeCommand mergeCommand;
+  private final MergeCommandRequest request = new MergeCommandRequest();
+
+  MergeCommandBuilder(MergeCommand mergeCommand) {
+    this.mergeCommand = mergeCommand;
+  }
+
+  /**
+   * Use this to set the branch that should be merged into the target branch.
+   *
+   * <b>This is mandatory.</b>
+   *
+   * @return This builder instance.
+   */
+  public MergeCommandBuilder setBranchToMerge(String branchToMerge) {
+    request.setBranchToMerge(branchToMerge);
+    return this;
+  }
+
+  /**
+   * Use this to set the target branch the other branch should be merged into.
+   *
+   * <b>This is mandatory.</b>
+   *
+   * @return This builder instance.
+   */
+  public MergeCommandBuilder setTargetBranch(String targetBranch) {
+    request.setTargetBranch(targetBranch);
+    return this;
+  }
+
+  /**
+   * Use this to set the author of the merge commit manually. If this is omitted, the currently logged in user will be
+   * used instead.
+   *
+   * This is optional and for {@link #executeMerge()} only.
+   *
+   * @return This builder instance.
+   */
+  public MergeCommandBuilder setAuthor(Person author) {
+    request.setAuthor(author);
+    return this;
+  }
+
+  /**
+   * Use this to set a template for the commit message. If no message is set, a default message will be used.
+   *
+   * You can use the placeholder <code>{0}</code> for the branch to be merged and <code>{1}</code> for the target
+   * branch, eg.:
+   *
+   * <pre><code>
+   * ...setMessageTemplate("Merge of {0} into {1}")...
+   * </code></pre>
+   *
+   * This is optional and for {@link #executeMerge()} only.
+   *
+   * @return This builder instance.
+   */
+  public MergeCommandBuilder setMessageTemplate(String messageTemplate) {
+    request.setMessageTemplate(messageTemplate);
+    return this;
+  }
+
+  /**
+   * Use this to reset the command.
+   * @return This builder instance.
+   */
+  public MergeCommandBuilder reset() {
+    request.reset();
+    return this;
+  }
+
+  /**
+   * Use this to actually do the merge. If an automatic merge is not possible, {@link MergeCommandResult#isSuccess()}
+   * will return <code>false</code>.
+   *
+   * @return The result of the merge.
+   */
+  public MergeCommandResult executeMerge() {
+    Preconditions.checkArgument(request.isValid(), "revision to merge and target revision is required");
+    return mergeCommand.merge(request);
+  }
+
+  /**
+   * Use this to check whether the given branches can be merged autmatically. If this is possible,
+   * {@link MergeDryRunCommandResult#isMergeable()} will return <code>true</code>.
+   *
+   * @return The result whether the given branches can be merged automatically.
+   */
+  public MergeDryRunCommandResult dryRun() {
+    Preconditions.checkArgument(request.isValid(), "revision to merge and target revision is required");
+    return mergeCommand.dryRun(request);
+  }
+}

scm-core/src/main/java/sonia/scm/repository/api/MergeCommandResult.java

@@ -0,0 +1,44 @@
+package sonia.scm.repository.api;
+
+import java.util.Collection;
+import java.util.HashSet;
+
+import static java.util.Collections.emptyList;
+import static java.util.Collections.unmodifiableCollection;
+
+/**
+ * This class keeps the result of a merge of branches. Use {@link #isSuccess()} to check whether the merge was
+ * sucessfully executed. If the result is <code>false</code> the merge could not be done without conflicts. In this
+ * case you can use {@link #getFilesWithConflict()} to get a list of files with merge conflicts.
+ */
+public class MergeCommandResult {
+  private final Collection<String> filesWithConflict;
+
+  private MergeCommandResult(Collection<String> filesWithConflict) {
+    this.filesWithConflict = filesWithConflict;
+  }
+
+  public static MergeCommandResult success() {
+    return new MergeCommandResult(emptyList());
+  }
+
+  public static MergeCommandResult failure(Collection<String> filesWithConflict) {
+    return new MergeCommandResult(new HashSet<>(filesWithConflict));
+  }
+
+  /**
+   * If this returns <code>true</code>, the merge was successfull. If this returns <code>false</code> there were
+   * merge conflicts. In this case you can use {@link #getFilesWithConflict()} to check what files could not be merged.
+   */
+  public boolean isSuccess() {
+    return filesWithConflict.isEmpty();
+  }
+
+  /**
+   * If the merge was not successful ({@link #isSuccess()} returns <code>false</code>) this will give you a list of
+   * file paths that could not be merged automatically.
+   */
+  public Collection<String> getFilesWithConflict() {
+    return unmodifiableCollection(filesWithConflict);
+  }
+}

scm-core/src/main/java/sonia/scm/repository/api/MergeDryRunCommandResult.java

@@ -0,0 +1,22 @@
+package sonia.scm.repository.api;
+
+/**
+ * This class keeps the result of a merge dry run. Use {@link #isMergeable()} to check whether an automatic merge is
+ * possible or not.
+ */
+public class MergeDryRunCommandResult {
+
+  private final boolean mergeable;
+
+  public MergeDryRunCommandResult(boolean mergeable) {
+    this.mergeable = mergeable;
+  }
+
+  /**
+   * This will return <code>true</code>, when an automatic merge is possible <em>at the moment</em>; <code>false</code>
+   * otherwise.
+   */
+  public boolean isMergeable() {
+    return mergeable;
+  }
+}

scm-core/src/main/java/sonia/scm/repository/api/ModificationsCommandBuilder.java

@@ -13,7 +13,6 @@ import sonia.scm.repository.Modifications;
 import sonia.scm.repository.PreProcessorUtil;
 import sonia.scm.repository.Repository;
 import sonia.scm.repository.RepositoryCacheKey;
-import sonia.scm.repository.RevisionNotFoundException;
 import sonia.scm.repository.spi.ModificationsCommand;
 import sonia.scm.repository.spi.ModificationsCommandRequest;
 
@@ -67,7 +66,7 @@ public final class ModificationsCommandBuilder {
     return this;
   }
 
-  public Modifications getModifications() throws IOException, RevisionNotFoundException {
+  public Modifications getModifications() throws IOException {
     Modifications modifications;
     if (disableCache) {
       log.info("Get modifications for {} with disabled cache", request);

scm-core/src/main/java/sonia/scm/repository/api/RepositoryService.java

@@ -79,6 +79,7 @@ import java.util.stream.Stream;
  * @apiviz.uses sonia.scm.repository.api.PushCommandBuilder
  * @apiviz.uses sonia.scm.repository.api.BundleCommandBuilder
  * @apiviz.uses sonia.scm.repository.api.UnbundleCommandBuilder
+ * @apiviz.uses sonia.scm.repository.api.MergeCommandBuilder
  * @since 1.17
  */
 @Slf4j
@@ -353,6 +354,22 @@ public final class RepositoryService implements Closeable {
       repository);
   }
 
+  /**
+   * The merge command executes a merge of two branches. It is possible to do a dry run to check, whether the given
+   * branches can be merged without conflicts.
+   *
+   * @return instance of {@link MergeCommandBuilder}
+   * @throws CommandNotSupportedException if the command is not supported
+   *                                      by the implementation of the repository service provider.
+   * @since 2.0.0
+   */
+  public MergeCommandBuilder gerMergeCommand() {
+    logger.debug("create unbundle command for repository {}",
+      repository.getNamespaceAndName());
+
+    return new MergeCommandBuilder(provider.getMergeCommand());
+  }
+
   /**
    * Returns true if the command is supported by the repository service.
    *

scm-core/src/main/java/sonia/scm/repository/api/RepositoryServiceFactory.java

@@ -45,6 +45,7 @@ import com.google.inject.Singleton;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import sonia.scm.HandlerEventType;
+import sonia.scm.NotFoundException;
 import sonia.scm.cache.Cache;
 import sonia.scm.cache.CacheManager;
 import sonia.scm.config.ScmConfiguration;
@@ -57,7 +58,6 @@ import sonia.scm.repository.Repository;
 import sonia.scm.repository.RepositoryCacheKeyPredicate;
 import sonia.scm.repository.RepositoryEvent;
 import sonia.scm.repository.RepositoryManager;
-import sonia.scm.repository.RepositoryNotFoundException;
 import sonia.scm.repository.RepositoryPermissions;
 import sonia.scm.repository.spi.RepositoryServiceProvider;
 import sonia.scm.repository.spi.RepositoryServiceResolver;
@@ -65,6 +65,9 @@ import sonia.scm.security.ScmSecurityException;
 
 import java.util.Set;
 
+import static sonia.scm.ContextEntry.ContextBuilder.entity;
+import static sonia.scm.NotFoundException.notFound;
+
 //~--- JDK imports ------------------------------------------------------------
 
 /**
@@ -161,7 +164,7 @@ public final class RepositoryServiceFactory
    * @return a implementation of RepositoryService
    *         for the given type of repository
    *
-   * @throws RepositoryNotFoundException if no repository
+   * @throws NotFoundException if no repository
    *         with the given id is available
    * @throws RepositoryServiceNotFoundException if no repository service
    *         implementation for this kind of repository is available
@@ -169,7 +172,7 @@ public final class RepositoryServiceFactory
    * @throws ScmSecurityException if current user has not read permissions
    *         for that repository
    */
-  public RepositoryService create(String repositoryId) throws RepositoryNotFoundException {
+  public RepositoryService create(String repositoryId) {
     Preconditions.checkArgument(!Strings.isNullOrEmpty(repositoryId),
       "a non empty repositoryId is required");
 
@@ -177,7 +180,7 @@ public final class RepositoryServiceFactory
 
     if (repository == null)
     {
-      throw new RepositoryNotFoundException(repositoryId);
+      throw new NotFoundException(Repository.class, repositoryId);
     }
 
     return create(repository);
@@ -192,7 +195,7 @@ public final class RepositoryServiceFactory
    * @return a implementation of RepositoryService
    *         for the given type of repository
    *
-   * @throws RepositoryNotFoundException if no repository
+   * @throws NotFoundException if no repository
    *         with the given id is available
    * @throws RepositoryServiceNotFoundException if no repository service
    *         implementation for this kind of repository is available
@@ -201,7 +204,6 @@ public final class RepositoryServiceFactory
    *         for that repository
    */
   public RepositoryService create(NamespaceAndName namespaceAndName)
-    throws RepositoryNotFoundException
   {
     Preconditions.checkArgument(namespaceAndName != null,
       "a non empty namespace and name is required");
@@ -210,7 +212,7 @@ public final class RepositoryServiceFactory
 
     if (repository == null)
     {
-      throw new RepositoryNotFoundException(namespaceAndName);
+      throw notFound(entity(namespaceAndName));
     }
 
     return create(repository);

scm-core/src/main/java/sonia/scm/repository/spi/BrowseCommand.java

@@ -35,7 +35,6 @@ package sonia.scm.repository.spi;
 
 //~--- non-JDK imports --------------------------------------------------------
 
-import sonia.scm.NotFoundException;
 import sonia.scm.repository.BrowserResult;
 
 import java.io.IOException;
@@ -60,5 +59,5 @@ public interface BrowseCommand
    *
    * @throws IOException
    */
-  BrowserResult getBrowserResult(BrowseCommandRequest request) throws IOException, NotFoundException;
+  BrowserResult getBrowserResult(BrowseCommandRequest request) throws IOException;
 }

scm-core/src/main/java/sonia/scm/repository/spi/CatCommand.java

@@ -33,9 +33,6 @@
 
 package sonia.scm.repository.spi;
 
-import sonia.scm.repository.PathNotFoundException;
-import sonia.scm.repository.RevisionNotFoundException;
-
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -47,7 +44,7 @@ import java.io.OutputStream;
  */
 public interface CatCommand {
 
-  void getCatResult(CatCommandRequest request, OutputStream output) throws IOException, RevisionNotFoundException, PathNotFoundException;
+  void getCatResult(CatCommandRequest request, OutputStream output) throws IOException;
 
-  InputStream getCatResultStream(CatCommandRequest request) throws IOException, RevisionNotFoundException, PathNotFoundException;
+  InputStream getCatResultStream(CatCommandRequest request) throws IOException;
 }

scm-core/src/main/java/sonia/scm/repository/spi/DiffCommand.java

@@ -33,8 +33,6 @@
 
 package sonia.scm.repository.spi;
 
-import sonia.scm.repository.RevisionNotFoundException;
-
 import java.io.IOException;
 import java.io.OutputStream;
 
@@ -56,5 +54,5 @@ public interface DiffCommand
    * @throws IOException
    * @throws RuntimeException
    */
-  public void getDiffResult(DiffCommandRequest request, OutputStream output) throws IOException, RevisionNotFoundException;
+  public void getDiffResult(DiffCommandRequest request, OutputStream output) throws IOException;
 }

scm-core/src/main/java/sonia/scm/repository/spi/DiffCommandRequest.java

@@ -109,7 +109,10 @@ public final class DiffCommandRequest extends FileBaseCommandRequest
     this.format = format;
   }
 
-  //~--- get methods ----------------------------------------------------------
+  public void setAncestorChangeset(String ancestorChangeset) {
+    this.ancestorChangeset = ancestorChangeset;
+  }
+//~--- get methods ----------------------------------------------------------
 
   /**
    * Return the output format of the diff command.
@@ -124,8 +127,13 @@ public final class DiffCommandRequest extends FileBaseCommandRequest
     return format;
   }
 
-  //~--- fields ---------------------------------------------------------------
+  public String getAncestorChangeset() {
+    return ancestorChangeset;
+  }
+//~--- fields ---------------------------------------------------------------
 
   /** diff format */
   private DiffFormat format = DiffFormat.NATIVE;
+
+  private String ancestorChangeset;
 }

scm-core/src/main/java/sonia/scm/repository/spi/HookEventFacade.java

@@ -40,10 +40,12 @@ import sonia.scm.repository.Repository;
 import sonia.scm.repository.RepositoryHookEvent;
 import sonia.scm.repository.RepositoryHookType;
 import sonia.scm.repository.RepositoryManager;
-import sonia.scm.repository.RepositoryNotFoundException;
 import sonia.scm.repository.api.HookContext;
 import sonia.scm.repository.api.HookContextFactory;
 
+import static sonia.scm.ContextEntry.ContextBuilder.entity;
+import static sonia.scm.NotFoundException.notFound;
+
 /**
  *
  * @author Sebastian Sdorra
@@ -71,18 +73,18 @@ public final class HookEventFacade
 
   //~--- methods --------------------------------------------------------------
 
-  public HookEventHandler handle(String id) throws RepositoryNotFoundException {
+  public HookEventHandler handle(String id) {
     return handle(repositoryManagerProvider.get().get(id));
   }
 
-  public HookEventHandler handle(NamespaceAndName namespaceAndName) throws RepositoryNotFoundException {
+  public HookEventHandler handle(NamespaceAndName namespaceAndName) {
     return handle(repositoryManagerProvider.get().get(namespaceAndName));
   }
 
-  public HookEventHandler handle(Repository repository) throws RepositoryNotFoundException {
+  public HookEventHandler handle(Repository repository) {
     if (repository == null)
     {
-      throw new RepositoryNotFoundException(repository);
+      throw notFound(entity(repository));
     }
 
     return new HookEventHandler(repositoryManagerProvider.get(),

scm-core/src/main/java/sonia/scm/repository/spi/LogCommand.java

@@ -37,7 +37,6 @@ package sonia.scm.repository.spi;
 
 import sonia.scm.repository.Changeset;
 import sonia.scm.repository.ChangesetPagingResult;
-import sonia.scm.repository.RevisionNotFoundException;
 
 import java.io.IOException;
 
@@ -50,7 +49,7 @@ import java.io.IOException;
  */
 public interface LogCommand {
 
-  Changeset getChangeset(String id) throws IOException, RevisionNotFoundException;
+  Changeset getChangeset(String id) throws IOException;
 
-  ChangesetPagingResult getChangesets(LogCommandRequest request) throws IOException, RevisionNotFoundException;
+  ChangesetPagingResult getChangesets(LogCommandRequest request) throws IOException;
 }

scm-core/src/main/java/sonia/scm/repository/spi/LogCommandRequest.java

@@ -84,7 +84,8 @@ public final class LogCommandRequest implements Serializable, Resetable
       && Objects.equal(pagingStart, other.pagingStart)
       && Objects.equal(pagingLimit, other.pagingLimit)
       && Objects.equal(path, other.path) 
-      && Objects.equal(branch, other.branch);
+      && Objects.equal(branch, other.branch)
+      && Objects.equal(ancestorChangeset, other.ancestorChangeset);
     //J+
   }
 
@@ -98,7 +99,7 @@ public final class LogCommandRequest implements Serializable, Resetable
   public int hashCode()
   {
     return Objects.hashCode(startChangeset, endChangeset, pagingStart,
-      pagingLimit, path, branch);
+      pagingLimit, path, branch, ancestorChangeset);
   }
 
   /**
@@ -114,6 +115,7 @@ public final class LogCommandRequest implements Serializable, Resetable
     pagingLimit = 20;
     path = null;
     branch = null;
+    ancestorChangeset = null;
   }
 
   /**
@@ -133,6 +135,7 @@ public final class LogCommandRequest implements Serializable, Resetable
                   .add("pagingLimit", pagingLimit)
                   .add("path", path)
                   .add("branch", branch)
+                  .add("ancestorChangeset", ancestorChangeset)
                   .toString();
     //J+
   }
@@ -205,6 +208,10 @@ public final class LogCommandRequest implements Serializable, Resetable
     this.startChangeset = startChangeset;
   }
 
+  public void setAncestorChangeset(String ancestorChangeset) {
+    this.ancestorChangeset = ancestorChangeset;
+  }
+
   //~--- get methods ----------------------------------------------------------
 
   /**
@@ -284,6 +291,10 @@ public final class LogCommandRequest implements Serializable, Resetable
     return pagingLimit < 0;
   }
 
+  public String getAncestorChangeset() {
+    return ancestorChangeset;
+  }
+
   //~--- fields ---------------------------------------------------------------
 
   /** Field description */
@@ -303,4 +314,6 @@ public final class LogCommandRequest implements Serializable, Resetable
 
   /** Field description */
   private String startChangeset;
+
+  private String ancestorChangeset;
 }

scm-core/src/main/java/sonia/scm/repository/spi/MergeCommand.java

@@ -0,0 +1,10 @@
+package sonia.scm.repository.spi;
+
+import sonia.scm.repository.api.MergeCommandResult;
+import sonia.scm.repository.api.MergeDryRunCommandResult;
+
+public interface MergeCommand {
+  MergeCommandResult merge(MergeCommandRequest request);
+
+  MergeDryRunCommandResult dryRun(MergeCommandRequest request);
+}

scm-core/src/main/java/sonia/scm/repository/spi/MergeCommandRequest.java

@@ -0,0 +1,93 @@
+package sonia.scm.repository.spi;
+
+import com.google.common.base.MoreObjects;
+import com.google.common.base.Objects;
+import com.google.common.base.Strings;
+import sonia.scm.Validateable;
+import sonia.scm.repository.Person;
+import sonia.scm.util.Util;
+
+import java.io.Serializable;
+
+public class MergeCommandRequest implements Validateable, Resetable, Serializable, Cloneable {
+
+  private static final long serialVersionUID = -2650236557922431528L;
+
+  private String branchToMerge;
+  private String targetBranch;
+  private Person author;
+  private String messageTemplate;
+
+  public String getBranchToMerge() {
+    return branchToMerge;
+  }
+
+  public void setBranchToMerge(String branchToMerge) {
+    this.branchToMerge = branchToMerge;
+  }
+
+  public String getTargetBranch() {
+    return targetBranch;
+  }
+
+  public void setTargetBranch(String targetBranch) {
+    this.targetBranch = targetBranch;
+  }
+
+  public Person getAuthor() {
+    return author;
+  }
+
+  public void setAuthor(Person author) {
+    this.author = author;
+  }
+
+  public String getMessageTemplate() {
+    return messageTemplate;
+  }
+
+  public void setMessageTemplate(String messageTemplate) {
+    this.messageTemplate = messageTemplate;
+  }
+
+  public boolean isValid() {
+    return !Strings.isNullOrEmpty(getBranchToMerge())
+      && !Strings.isNullOrEmpty(getTargetBranch());
+  }
+
+  public void reset() {
+    this.setBranchToMerge(null);
+    this.setTargetBranch(null);
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (obj == null) {
+      return false;
+    }
+
+    if (getClass() != obj.getClass()) {
+      return false;
+    }
+
+    final MergeCommandRequest other = (MergeCommandRequest) obj;
+
+    return Objects.equal(branchToMerge, other.branchToMerge)
+      && Objects.equal(targetBranch, other.targetBranch)
+      && Objects.equal(author, other.author);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hashCode(branchToMerge, targetBranch, author);
+  }
+
+  @Override
+  public String toString() {
+    return MoreObjects.toStringHelper(this)
+      .add("branchToMerge", branchToMerge)
+      .add("targetBranch", targetBranch)
+      .add("author", author)
+      .toString();
+  }
+}

scm-core/src/main/java/sonia/scm/repository/spi/ModificationsCommand.java

@@ -32,7 +32,6 @@
 package sonia.scm.repository.spi;
 
 import sonia.scm.repository.Modifications;
-import sonia.scm.repository.RevisionNotFoundException;
 
 import java.io.IOException;
 
@@ -46,8 +45,8 @@ import java.io.IOException;
  */
 public interface ModificationsCommand {
 
-  Modifications getModifications(String revision) throws IOException, RevisionNotFoundException;
+  Modifications getModifications(String revision) throws IOException;
 
-  Modifications getModifications(ModificationsCommandRequest request) throws IOException, RevisionNotFoundException;
+  Modifications getModifications(ModificationsCommandRequest request) throws IOException;
 
 }

scm-core/src/main/java/sonia/scm/repository/spi/RepositoryServiceProvider.java

@@ -251,4 +251,12 @@ public abstract class RepositoryServiceProvider implements Closeable
   {
     throw new CommandNotSupportedException(Command.UNBUNDLE);
   }
+
+  /**
+   * @since 2.0
+   */
+  public MergeCommand getMergeCommand()
+  {
+    throw new CommandNotSupportedException(Command.MERGE);
+  }
 }

scm-core/src/main/java/sonia/scm/user/ChangePasswordNotAllowedException.java

@@ -1,11 +1,19 @@
 package sonia.scm.user;
 
-public class ChangePasswordNotAllowedException extends RuntimeException {
+import sonia.scm.ContextEntry;
+import sonia.scm.ExceptionWithContext;
 
+public class ChangePasswordNotAllowedException extends ExceptionWithContext {
+
+  private static final String CODE = "9BR7qpDAe1";
   public static final String WRONG_USER_TYPE = "User of type %s are not allowed to change password";
 
-  public ChangePasswordNotAllowedException(String type) {
-    super(String.format(WRONG_USER_TYPE, type));
+  public ChangePasswordNotAllowedException(ContextEntry.ContextBuilder context, String type) {
+    super(context.build(), String.format(WRONG_USER_TYPE, type));
   }
 
+  @Override
+  public String getCode() {
+    return CODE;
+  }
 }

scm-core/src/main/java/sonia/scm/user/InvalidPasswordException.java

@@ -1,8 +1,18 @@
 package sonia.scm.user;
 
-public class InvalidPasswordException extends RuntimeException {
+import sonia.scm.ContextEntry;
+import sonia.scm.ExceptionWithContext;
 
-  public InvalidPasswordException() {
-    super("The given Password does not match with the stored one.");
+public class InvalidPasswordException extends ExceptionWithContext {
+
+  private static final String CODE = "8YR7aawFW1";
+
+  public InvalidPasswordException(ContextEntry.ContextBuilder context) {
+    super(context.build(), "The given old password does not match with the stored one.");
+  }
+
+  @Override
+  public String getCode() {
+    return CODE;
   }
 }

scm-core/src/main/java/sonia/scm/web/VndMediaType.java

@@ -44,6 +44,7 @@ public class VndMediaType {
 
   public static final String ME = PREFIX + "me" + SUFFIX;
   public static final String SOURCE = PREFIX + "source" + SUFFIX;
+  public static final String ERROR_TYPE = PREFIX + "error" + SUFFIX;
 
   private VndMediaType() {
   }

scm-core/src/main/java/sonia/scm/web/filter/AuthenticationFilter.java

@@ -301,7 +301,7 @@ public class AuthenticationFilter extends HttpFilter
       }
     }
 
-    chain.doFilter(new SecurityHttpServletRequestWrapper(request, username),
+    chain.doFilter(new PropagatePrincipleServletRequestWrapper(request, username),
       response);
   }
 

scm-core/src/main/java/sonia/scm/web/filter/PropagatePrincipleServletRequestWrapper.java

@@ -38,37 +38,17 @@ package sonia.scm.web.filter;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletRequestWrapper;
 
-/**
- *
- * @author Sebastian Sdorra
- */
-public class SecurityHttpServletRequestWrapper extends HttpServletRequestWrapper
-{
+public class PropagatePrincipleServletRequestWrapper extends HttpServletRequestWrapper {
 
- /**
-   * Constructs ...
-   *
-   *
-   * @param request
-   * @param principal
-   */
-  public SecurityHttpServletRequestWrapper(HttpServletRequest request,
-    String principal)
-  {
+  private final String principal;
+
+  public PropagatePrincipleServletRequestWrapper(HttpServletRequest request, String principal) {
     super(request);
     this.principal = principal;
   }
 
-  //~--- get methods ----------------------------------------------------------
-
   @Override
-  public String getRemoteUser()
-  {
+  public String getRemoteUser() {
     return principal;
   }
-
-  //~--- fields ---------------------------------------------------------------
-
-  /** Field description */
-  private final String principal;
 }

scm-core/src/test/java/sonia/scm/security/SyncingRealmHelperTest.java

@@ -43,7 +43,6 @@ import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.junit.MockitoJUnitRunner;
 import sonia.scm.AlreadyExistsException;
-import sonia.scm.NotFoundException;
 import sonia.scm.group.Group;
 import sonia.scm.group.GroupManager;
 import sonia.scm.group.GroupNames;
@@ -132,7 +131,7 @@ public class SyncingRealmHelperTest {
    * @throws IOException
    */
   @Test
-  public void testStoreGroupCreate() throws AlreadyExistsException {
+  public void testStoreGroupCreate() {
     Group group = new Group("unit-test", "heartOfGold");
 
     helper.store(group);
@@ -143,7 +142,7 @@ public class SyncingRealmHelperTest {
    * Tests {@link SyncingRealmHelper#store(Group)}.
    */
   @Test(expected = IllegalStateException.class)
-  public void testStoreGroupFailure() throws AlreadyExistsException {
+  public void testStoreGroupFailure() {
     Group group = new Group("unit-test", "heartOfGold");
 
     doThrow(AlreadyExistsException.class).when(groupManager).create(group);
@@ -169,7 +168,7 @@ public class SyncingRealmHelperTest {
    * @throws IOException
    */
   @Test
-  public void testStoreUserCreate() throws AlreadyExistsException {
+  public void testStoreUserCreate() {
     User user = new User("tricia");
 
     helper.store(user);
@@ -180,7 +179,7 @@ public class SyncingRealmHelperTest {
    * Tests {@link SyncingRealmHelper#store(User)} with a thrown {@link AlreadyExistsException}.
    */
   @Test(expected = IllegalStateException.class)
-  public void testStoreUserFailure() throws AlreadyExistsException {
+  public void testStoreUserFailure() {
     User user = new User("tricia");
 
     doThrow(AlreadyExistsException.class).when(userManager).create(user);