Changing content item API

11 files changed, 380 insertions, 175 deletions

diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaArtifact.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaArtifact.java
index 26b0449ba..b65fa7400 100644
--- a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaArtifact.java
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaArtifact.java
@@ -22,8 +22,6 @@ package org.apache.archiva.repository.content.base;
 import org.apache.archiva.repository.content.Artifact;
 import org.apache.archiva.repository.content.ArtifactType;
 import org.apache.archiva.repository.content.BaseArtifactTypes;
-import org.apache.archiva.repository.content.ContentItem;
-import org.apache.archiva.repository.content.DataItem;
 import org.apache.archiva.repository.content.Version;
 import org.apache.archiva.repository.content.base.builder.ArtifactOptBuilder;
 import org.apache.archiva.repository.content.base.builder.ArtifactVersionBuilder;
@@ -52,7 +50,7 @@ import org.apache.commons.lang3.StringUtils;
  *
  * @author Martin Stockhammer <martin_s@apache.org>
  */
-public class ArchivaArtifact extends ArchivaContentItem implements Artifact
+public class ArchivaArtifact extends BaseContentItem implements Artifact
 {
     private String id;
     private String artifactVersion;
@@ -135,8 +133,6 @@ public class ArchivaArtifact extends ArchivaContentItem implements Artifact
     {
         if ( this == o ) return true;
         if ( o == null || getClass( ) != o.getClass( ) ) return false;
-        if ( !super.equals( o ) ) return false;
-
         ArchivaArtifact that = (ArchivaArtifact) o;
 
         if ( !id.equals( that.id ) ) return false;
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaContentItem.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaContentItem.java
index 7e15d61be..acba93b4f 100644
--- a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaContentItem.java
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaContentItem.java
@@ -21,105 +21,39 @@ package org.apache.archiva.repository.content.base;
 
 import org.apache.archiva.repository.ManagedRepositoryContent;
 import org.apache.archiva.repository.content.ContentItem;
+import org.apache.archiva.repository.content.Namespace;
 import org.apache.archiva.repository.content.Project;
-import org.apache.archiva.repository.content.base.builder.OptBuilder;
+import org.apache.archiva.repository.content.Version;
+import org.apache.archiva.repository.content.base.builder.ArchivaContentItemOptBuilder;
 import org.apache.archiva.repository.content.base.builder.WithAssetBuilder;
-import org.apache.archiva.repository.content.base.builder.WithRepositoryBuilder;
 import org.apache.archiva.repository.storage.StorageAsset;
-import org.apache.commons.lang3.StringUtils;
-
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.Map;
 
 /**
  * Abstract implementation of ContentItem interface.
  * <p>
  * The attribute map is created, when the first values are put to the map.
  */
-public abstract class ArchivaContentItem implements ContentItem
+public class ArchivaContentItem extends BaseContentItem implements ContentItem
 {
 
-    private Map<String, String> attributes;
-    private ManagedRepositoryContent repository;
-    private StorageAsset asset;
-
-    @Override
-    public <T extends Project> T adapt( Class<T> clazz )
-    {
-        return (T) this;
-    }
-
-    @Override
-    public <T extends Project> boolean supports( Class<T> clazz )
-    {
-        return clazz != null && clazz.isAssignableFrom( this.getClass( ) );
-    }
-
-
-    /**
-     * Does lazy initialization of the attributes map.
-     * Returns a unmodifiable map.
-     *
-     * @return unmodifiable map of attributes
-     */
-    @Override
-    public Map<String, String> getAttributes( )
-    {
-        if ( this.attributes == null )
-        {
-            return Collections.emptyMap( );
-        }
-        else
-        {
-            return Collections.unmodifiableMap( this.attributes );
-        }
-    }
 
     /**
-     * Adds a attribute value. The key must not be <code>null</code>.
+     * Creates the builder for creating new archiva project instances.
+     * You have to set all required attributes before you can call the build() method.
      *
-     * @param key   the attribute key
-     * @param value the attribute value
-     * @throws IllegalArgumentException if the key is <code>null</code> or empty
+     * @param storageAsset the asset
+     * @return a builder instance
      */
-    public void putAttribute( String key, String value ) throws IllegalArgumentException
-    {
-        if ( this.attributes == null )
-        {
-            this.attributes = new HashMap<>( );
-        }
-        if ( StringUtils.isEmpty( key ) )
-        {
-            throw new IllegalArgumentException( "Key value must not be empty or null" );
-        }
-        this.attributes.put( key, value );
-    }
-
-    @Override
-    public String getAttribute( String key )
+    public static ArchivaContentItemOptBuilder withAsset( StorageAsset storageAsset )
     {
-        if ( this.attributes == null )
-        {
-            return null;
-        }
-        else
-        {
-            return this.attributes.get( key );
-        }
+        return new ArchivaContentItemBuilder().withAsset( storageAsset );
     }
 
-    @Override
-    public ManagedRepositoryContent getRepository( )
+    public static WithAssetBuilder<ArchivaContentItemOptBuilder> withRepository( ManagedRepositoryContent repository )
     {
-        return repository;
+        return new ArchivaContentItemBuilder().withRepository( repository );
     }
 
-    @Override
-    public StorageAsset getAsset( )
-    {
-        return asset;
-    }
 
     @Override
     public boolean equals( Object o )
@@ -150,86 +84,56 @@ public abstract class ArchivaContentItem implements ContentItem
      */
 
 
-    /**
-     * Builder for content item. Must be extended by subclasses.
-     * The builder uses chained interfaces for building the required attributes. That means you have to set
-     * some certain attributes, before you can build the content item instance via the {@link #build()} method.
-     * <p>
-     * Subclasses should extend from this class and provide the interface/class for the destination item,
-     * a interface for the optional attributes and a interface that is returned after the last required attribute is
-     * set.
-     * <p>
-     * The interface for optional attributes should inherit from {@link OptBuilder}
-     *
-     * @param <I> the item class that should be built
-     * @param <O> the class/interface for the optional attributes
-     * @param <N> the class/interface for the next (required) attribute after the base attributes are set
-     */
-    protected abstract static class ContentItemBuilder<I extends ArchivaContentItem, O extends OptBuilder<I, O>, N>
-        implements WithRepositoryBuilder, WithAssetBuilder<N>,
-        OptBuilder<I, O>
+    public static final class ArchivaContentItemBuilder extends ContentItemBuilder<ArchivaContentItem, ArchivaContentItemOptBuilder, ArchivaContentItemOptBuilder>
+        implements ArchivaContentItemOptBuilder
     {
 
-        protected I item;
-
-        protected ContentItemBuilder( I item )
+        private ArchivaContentItemBuilder(  )
         {
-            this.item = item;
+            super( new ArchivaContentItem() );
         }
 
-        protected abstract O getOptBuilder( );
-
-        protected abstract N getNextBuilder( );
+        @Override
+        public ArchivaContentItemOptBuilder getOptBuilder( )
+        {
+            return this;
+        }
 
         @Override
-        public WithAssetBuilder<N> withRepository( ManagedRepositoryContent repository )
+        public ArchivaContentItemOptBuilder getNextBuilder( )
         {
-            if ( repository == null )
-            {
-                throw new IllegalArgumentException( "Repository may not be null" );
-            }
-            ( (ArchivaContentItem) item ).repository = repository;
             return this;
         }
 
+
         @Override
-        public N withAsset( StorageAsset asset )
+        public ArchivaContentItemOptBuilder withNamespace( Namespace namespace )
         {
-            if ( asset == null )
-            {
-                throw new IllegalArgumentException( "Asset may not be null" );
-            }
-            ( (ArchivaContentItem) item ).asset = asset;
-            return getNextBuilder( );
+            item.setCharacteristic( Namespace.class, namespace );
+            return this;
         }
 
         @Override
-        public O withAttribute( String key, String value )
+        public ArchivaContentItemOptBuilder withProject( Project project )
         {
-            if ( StringUtils.isEmpty( key ) )
-            {
-                throw new IllegalArgumentException( "Attribute key may not be null" );
-            }
-            item.putAttribute( key, value );
-            return getOptBuilder( );
+            item.setCharacteristic( Project.class, project );
+            return this;
         }
 
-        protected void setRepository( ManagedRepositoryContent repository )
+        @Override
+        public ArchivaContentItemOptBuilder withVersion( Version version )
         {
-            ( (ArchivaContentItem) item ).repository = repository;
+            item.setCharacteristic( Version.class, version );
+            return this;
         }
 
         @Override
-        public I build( )
+        public ArchivaContentItem build( )
         {
+            super.build( );
             return item;
         }
-
     }
 
-    @Override
-    public boolean exists( )
-    {
-        return asset.exists( );
-    }
+
 }
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaDataItem.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaDataItem.java
index cb13e1832..c825bb316 100644
--- a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaDataItem.java
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaDataItem.java
@@ -19,9 +19,7 @@ package org.apache.archiva.repository.content.base;
  * under the License.
  */
 
-import org.apache.archiva.repository.content.BaseArtifactTypes;
 import org.apache.archiva.repository.content.BaseDataItemTypes;
-import org.apache.archiva.repository.content.ContentItem;
 import org.apache.archiva.repository.content.DataItem;
 import org.apache.archiva.repository.content.DataItemType;
 import org.apache.archiva.repository.content.base.builder.DataItemOptBuilder;
@@ -49,10 +47,9 @@ import org.apache.commons.lang3.StringUtils;
  *
  * @author Martin Stockhammer <martin_s@apache.org>
  */
-public class ArchivaDataItem extends ArchivaContentItem implements DataItem
+public class ArchivaDataItem extends BaseContentItem implements DataItem
 {
     private String id;
-    private ContentItem parent;
     private String contentType;
     private DataItemType dataItemType;
 
@@ -68,12 +65,6 @@ public class ArchivaDataItem extends ArchivaContentItem implements DataItem
     }
 
     @Override
-    public ContentItem getParent( )
-    {
-        return parent;
-    }
-
-    @Override
     public String getContentType( )
     {
         return contentType;
@@ -109,7 +100,6 @@ public class ArchivaDataItem extends ArchivaContentItem implements DataItem
         ArchivaDataItem that = (ArchivaDataItem) o;
 
         if ( !id.equals( that.id ) ) return false;
-        if ( !parent.equals( that.parent ) ) return false;
         return dataItemType.equals(that.dataItemType );
     }
 
@@ -118,7 +108,6 @@ public class ArchivaDataItem extends ArchivaContentItem implements DataItem
     {
         int result = super.hashCode( );
         result = 31 * result + id.hashCode( );
-        result = 31 * result + parent.hashCode( );
         result = 31 * result + dataItemType.hashCode( );
         return result;
     }
@@ -126,9 +115,8 @@ public class ArchivaDataItem extends ArchivaContentItem implements DataItem
     @Override
     public String toString( )
     {
-        final StringBuilder sb = new StringBuilder( "ArchivaArtifact{" );
+        final StringBuilder sb = new StringBuilder( "ArchivaDataItem{" );
         sb.append( "id='" ).append( id ).append( '\'' );
-        sb.append( ", parent=" ).append( parent );
         sb.append( ", contentType='" ).append( contentType ).append( '\'' );
         sb.append( ", artifactType=" ).append( dataItemType );
         sb.append( '}' );
@@ -168,18 +156,6 @@ public class ArchivaDataItem extends ArchivaContentItem implements DataItem
         }
 
         @Override
-        public DataItemOptBuilder withParent( ContentItem parent )
-        {
-            if ( parent == null )
-            {
-                throw new IllegalArgumentException( "version may not be null" );
-            }
-            item.parent = parent;
-            super.setRepository( parent.getRepository( ) );
-            return this;
-        }
-
-        @Override
         public DataItemOptBuilder withId( String id )
         {
             if ( StringUtils.isEmpty( id ) )
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaNamespace.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaNamespace.java
index b85f25a60..9982ea0de 100644
--- a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaNamespace.java
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaNamespace.java
@@ -38,7 +38,7 @@ import java.util.regex.PatternSyntaxException;
  * @author Martin Stockhammer <martin_s@apache.org>
  * @since 3.0
  */
-public class ArchivaNamespace extends ArchivaContentItem implements Namespace
+public class ArchivaNamespace extends BaseContentItem implements Namespace
 {
     private String namespace;
     private List<String> namespacePath;
@@ -72,10 +72,9 @@ public class ArchivaNamespace extends ArchivaContentItem implements Namespace
     {
         if ( this == o ) return true;
         if ( o == null || getClass( ) != o.getClass( ) ) return false;
-        if ( !super.equals( o ) ) return false;
-
         ArchivaNamespace that = (ArchivaNamespace) o;
 
+        if (!repository.equals( that.repository )) return false;
         return namespace.equals( that.namespace );
     }
 
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaProject.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaProject.java
index ac72f6217..9fb9a0cf6 100644
--- a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaProject.java
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaProject.java
@@ -19,11 +19,15 @@ package org.apache.archiva.repository.content.base;
  * under the License.
  */
 
+import org.apache.archiva.repository.ManagedRepositoryContent;
 import org.apache.archiva.repository.content.Namespace;
 import org.apache.archiva.repository.content.Project;
 import org.apache.archiva.repository.content.base.builder.ProjectOptBuilder;
 import org.apache.archiva.repository.content.base.builder.ProjectWithIdBuilder;
+import org.apache.archiva.repository.content.base.builder.WithAssetBuilder;
+import org.apache.archiva.repository.content.base.builder.WithNamespaceBuilder;
 import org.apache.archiva.repository.content.base.builder.WithNamespaceObjectBuilder;
+import org.apache.archiva.repository.content.base.builder.WithProjectBuilder;
 import org.apache.archiva.repository.storage.StorageAsset;
 import org.apache.commons.lang3.StringUtils;
 
@@ -38,7 +42,7 @@ import org.apache.commons.lang3.StringUtils;
  * @author Martin Stockhammer <martin_s@apache.org>
  * @since 3.0
  */
-public class ArchivaProject extends ArchivaContentItem implements Project
+public class ArchivaProject extends BaseContentItem implements Project
 {
     private Namespace namespace;
     private String id;
@@ -62,6 +66,11 @@ public class ArchivaProject extends ArchivaContentItem implements Project
         return new Builder( ).withAsset( storageAsset );
     }
 
+    public static WithAssetBuilder<WithNamespaceObjectBuilder> withRepository( ManagedRepositoryContent repository )
+    {
+        return new ArchivaProject.Builder( ).withRepository( repository );
+    }
+
     @Override
     public Namespace getNamespace( )
     {
@@ -80,10 +89,10 @@ public class ArchivaProject extends ArchivaContentItem implements Project
     {
         if ( this == o ) return true;
         if ( o == null || getClass( ) != o.getClass( ) ) return false;
-        if ( !super.equals( o ) ) return false;
 
         ArchivaProject that = (ArchivaProject) o;
 
+        if (!repository.equals( that.repository )) return false;
         if ( !namespace.equals( that.namespace ) ) return false;
         return id.equals( that.id );
     }
@@ -100,7 +109,7 @@ public class ArchivaProject extends ArchivaContentItem implements Project
     @Override
     public String toString( )
     {
-        return id + ", namespace="+namespace.toString();
+        return "ArchivaProject{ "+id + ", namespace="+namespace.toString()+"}";
     }
 
     /*
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaVersion.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaVersion.java
index e10d3b1c5..c553c3bfc 100644
--- a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaVersion.java
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ArchivaVersion.java
@@ -19,9 +19,12 @@ package org.apache.archiva.repository.content.base;
  * under the License.
  */
 
+import org.apache.archiva.repository.ManagedRepositoryContent;
 import org.apache.archiva.repository.content.Project;
 import org.apache.archiva.repository.content.Version;
 import org.apache.archiva.repository.content.base.builder.VersionOptBuilder;
+import org.apache.archiva.repository.content.base.builder.WithAssetBuilder;
+import org.apache.archiva.repository.content.base.builder.WithNamespaceBuilder;
 import org.apache.archiva.repository.content.base.builder.WithProjectBuilder;
 import org.apache.archiva.repository.content.base.builder.WithVersionBuilder;
 import org.apache.archiva.repository.storage.StorageAsset;
@@ -41,7 +44,7 @@ import java.util.regex.PatternSyntaxException;
  * <p>
  * Two instances are equal, if the project and the version match in addition to the base attributes repository and asset.
  */
-public class ArchivaVersion extends ArchivaContentItem implements Version
+public class ArchivaVersion extends BaseContentItem implements Version
 {
 
     private String version;
@@ -66,6 +69,11 @@ public class ArchivaVersion extends ArchivaContentItem implements Version
         return new Builder( ).withAsset( storageAsset );
     }
 
+    public static WithAssetBuilder<WithProjectBuilder> withRepository( ManagedRepositoryContent repository )
+    {
+        return new ArchivaVersion.Builder( ).withRepository( repository );
+    }
+
     @Override
     public List<String> getVersionSegments( )
     {
@@ -90,10 +98,9 @@ public class ArchivaVersion extends ArchivaContentItem implements Version
     {
         if ( this == o ) return true;
         if ( o == null || getClass( ) != o.getClass( ) ) return false;
-        if ( !super.equals( o ) ) return false;
 
         ArchivaVersion that = (ArchivaVersion) o;
-
+        if (!repository.equals( that.repository )) return false;
         if ( !version.equals( that.version ) ) return false;
         return project.equals( that.project );
     }
@@ -110,7 +117,7 @@ public class ArchivaVersion extends ArchivaContentItem implements Version
     @Override
     public String toString( )
     {
-        return version+", project="+project.toString();
+        return "ArchivaVersion{ "+version+", project="+project.toString()+"}";
     }
 
     private static final class Builder extends ContentItemBuilder<ArchivaVersion, VersionOptBuilder, WithProjectBuilder>
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/BaseContentItem.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/BaseContentItem.java
new file mode 100644
index 000000000..3866131ec
--- /dev/null
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/BaseContentItem.java
@@ -0,0 +1,151 @@
+package org.apache.archiva.repository.content.base;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import org.apache.archiva.repository.ItemConversionException;
+import org.apache.archiva.repository.LayoutException;
+import org.apache.archiva.repository.ManagedRepositoryContent;
+import org.apache.archiva.repository.content.ContentItem;
+import org.apache.archiva.repository.storage.StorageAsset;
+import org.apache.commons.lang3.StringUtils;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * @author Martin Stockhammer <martin_s@apache.org>
+ */
+public abstract class BaseContentItem implements ContentItem
+{
+    protected ManagedRepositoryContent repository;
+    protected StorageAsset asset;
+    private Map<String, String> attributes;
+    private Map<Class<?>, ContentItem> characteristics  = new HashMap<>(  );
+    private Set<Class<?>> failedConversions = new HashSet<>(  );
+
+    @Override
+    public <T extends ContentItem> T adapt( Class<T> clazz ) throws ItemConversionException
+    {
+        if (characteristics.containsKey( clazz )) {
+            return (T) characteristics.get( clazz );
+        } else {
+            for ( Map.Entry<Class<?>, ? extends ContentItem> cEntry : characteristics.entrySet()) {
+                if (clazz.isAssignableFrom( cEntry.getKey() )) {
+                    return (T) cEntry.getValue( );
+                }
+            }
+            try  {
+                return repository.applyCharacteristic( clazz, this );
+            } catch ( LayoutException e ) {
+                throw new ItemConversionException( "Could not convert item to " + clazz, e );
+            }
+        }
+    }
+
+    @Override
+    public <T extends ContentItem> boolean hasCharacteristic( Class<T> clazz )
+    {
+        if (clazz == null) {
+            return false;
+        }
+        if ( characteristics.containsKey( clazz )
+                || characteristics.keySet( ).stream( ).anyMatch( cClass -> clazz.isAssignableFrom( cClass ) ) ) {
+            return true;
+        };
+        return false;
+    }
+
+    /**
+     * Does lazy initialization of the attributes map.
+     * Returns a unmodifiable map.
+     *
+     * @return unmodifiable map of attributes
+     */
+    @Override
+    public Map<String, String> getAttributes( )
+    {
+        if ( this.attributes == null )
+        {
+            return Collections.emptyMap( );
+        }
+        else
+        {
+            return Collections.unmodifiableMap( this.attributes );
+        }
+    }
+
+    /**
+     * Adds a attribute value. The key must not be <code>null</code>.
+     *
+     * @param key   the attribute key
+     * @param value the attribute value
+     * @throws IllegalArgumentException if the key is <code>null</code> or empty
+     */
+    public void putAttribute( String key, String value ) throws IllegalArgumentException
+    {
+        if ( this.attributes == null )
+        {
+            this.attributes = new HashMap<>( );
+        }
+        if ( StringUtils.isEmpty( key ) )
+        {
+            throw new IllegalArgumentException( "Key value must not be empty or null" );
+        }
+        this.attributes.put( key, value );
+    }
+
+    @Override
+    public String getAttribute( String key )
+    {
+        if ( this.attributes == null )
+        {
+            return null;
+        }
+        else
+        {
+            return this.attributes.get( key );
+        }
+    }
+
+    @Override
+    public ManagedRepositoryContent getRepository( )
+    {
+        return repository;
+    }
+
+    @Override
+    public StorageAsset getAsset( )
+    {
+        return asset;
+    }
+
+    @Override
+    public boolean exists( )
+    {
+        return asset.exists( );
+    }
+
+    public <T extends ContentItem> void setCharacteristic( Class<T> clazz, T item )
+    {
+        this.characteristics.put( clazz, item );
+    }
+}
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ContentItemBuilder.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ContentItemBuilder.java
new file mode 100644
index 000000000..dd3a53db7
--- /dev/null
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/ContentItemBuilder.java
@@ -0,0 +1,103 @@
+package org.apache.archiva.repository.content.base;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import org.apache.archiva.repository.ManagedRepositoryContent;
+import org.apache.archiva.repository.content.base.builder.OptBuilder;
+import org.apache.archiva.repository.content.base.builder.WithAssetBuilder;
+import org.apache.archiva.repository.content.base.builder.WithRepositoryBuilder;
+import org.apache.archiva.repository.storage.StorageAsset;
+import org.apache.commons.lang3.StringUtils;
+
+/**
+ * Builder for content item. Must be extended by subclasses.
+ * The builder uses chained interfaces for building the required attributes. That means you have to set
+ * some certain attributes, before you can build the content item instance via the {@link #build()} method.
+ * <p>
+ * Subclasses should extend from this class and provide the interface/class for the destination item,
+ * a interface for the optional attributes and a interface that is returned after the last required attribute is
+ * set.
+ * <p>
+ * The interface for optional attributes should inherit from {@link OptBuilder}
+ *
+ * @param <I> the item class that should be built
+ * @param <O> the class/interface for the optional attributes
+ * @param <N> the class/interface for the next (required) attribute after the base attributes are set
+ */
+abstract class ContentItemBuilder<I extends BaseContentItem, O extends OptBuilder<I, O>, N>
+    implements WithRepositoryBuilder, WithAssetBuilder<N>,
+    OptBuilder<I, O>
+{
+
+    protected I item;
+
+    protected ContentItemBuilder( I item )
+    {
+        this.item = item;
+    }
+
+    protected abstract O getOptBuilder( );
+
+    protected abstract N getNextBuilder( );
+
+    @Override
+    public WithAssetBuilder<N> withRepository( ManagedRepositoryContent repository )
+    {
+        if ( repository == null )
+        {
+            throw new IllegalArgumentException( "Repository may not be null" );
+        }
+        ( (BaseContentItem) item ).repository = repository;
+        return this;
+    }
+
+    @Override
+    public N withAsset( StorageAsset asset )
+    {
+        if ( asset == null )
+        {
+            throw new IllegalArgumentException( "Asset may not be null" );
+        }
+        ( (BaseContentItem) item ).asset = asset;
+        return getNextBuilder( );
+    }
+
+    @Override
+    public O withAttribute( String key, String value )
+    {
+        if ( StringUtils.isEmpty( key ) )
+        {
+            throw new IllegalArgumentException( "Attribute key may not be null" );
+        }
+        item.putAttribute( key, value );
+        return getOptBuilder( );
+    }
+
+    protected void setRepository( ManagedRepositoryContent repository )
+    {
+        item.repository = repository;
+    }
+
+    @Override
+    public I build( )
+    {
+        return item;
+    }
+
+}
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/builder/ArchivaContentItemOptBuilder.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/builder/ArchivaContentItemOptBuilder.java
new file mode 100644
index 000000000..36ca84375
--- /dev/null
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/builder/ArchivaContentItemOptBuilder.java
@@ -0,0 +1,38 @@
+package org.apache.archiva.repository.content.base.builder;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import org.apache.archiva.repository.content.Namespace;
+import org.apache.archiva.repository.content.Project;
+import org.apache.archiva.repository.content.Version;
+import org.apache.archiva.repository.content.base.ArchivaContentItem;
+
+/**
+ * @author Martin Stockhammer <martin_s@apache.org>
+ */
+public interface ArchivaContentItemOptBuilder extends OptBuilder<ArchivaContentItem, ArchivaContentItemOptBuilder>
+{
+    ArchivaContentItemOptBuilder withNamespace( Namespace namespace );
+
+    ArchivaContentItemOptBuilder withProject( Project project );
+
+    ArchivaContentItemOptBuilder withVersion( Version version );
+
+    ArchivaContentItem build();
+}
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/builder/DataItemOptBuilder.java b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/builder/DataItemOptBuilder.java
index 04da17d13..445946ec2 100644
--- a/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/builder/DataItemOptBuilder.java
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/main/java/org/apache/archiva/repository/content/base/builder/DataItemOptBuilder.java
@@ -32,8 +32,6 @@ public interface DataItemOptBuilder
     extends OptBuilder<ArchivaDataItem, DataItemOptBuilder>
 {
 
-    DataItemOptBuilder withParent( ContentItem parent );
-
     DataItemOptBuilder withContentType( String contentType );
 
     DataItemOptBuilder withDataType( DataItemType type );
diff --git a/archiva-modules/archiva-base/archiva-repository-layer/src/test/java/org/apache/archiva/repository/mock/ManagedRepositoryContentMock.java b/archiva-modules/archiva-base/archiva-repository-layer/src/test/java/org/apache/archiva/repository/mock/ManagedRepositoryContentMock.java
index dfd770380..2e7871d00 100644
--- a/archiva-modules/archiva-base/archiva-repository-layer/src/test/java/org/apache/archiva/repository/mock/ManagedRepositoryContentMock.java
+++ b/archiva-modules/archiva-base/archiva-repository-layer/src/test/java/org/apache/archiva/repository/mock/ManagedRepositoryContentMock.java
@@ -164,6 +164,12 @@ public class ManagedRepositoryContentMock implements ManagedRepositoryContent
     }
 
     @Override
+    public List<String> getArtifactVersions( ItemSelector selector ) throws ContentAccessException, IllegalArgumentException
+    {
+        return null;
+    }
+
+    @Override
     public List<? extends Artifact> getArtifacts( ContentItem item ) throws ContentAccessException
     {
         return null;
@@ -182,6 +188,24 @@ public class ManagedRepositoryContentMock implements ManagedRepositoryContent
     }
 
     @Override
+    public ContentItem getParent( ContentItem item )
+    {
+        return null;
+    }
+
+    @Override
+    public List<? extends ContentItem> getChildren( ContentItem item )
+    {
+        return null;
+    }
+
+    @Override
+    public <T extends ContentItem> T applyCharacteristic( Class<T> clazz, ContentItem item ) throws LayoutException
+    {
+        return null;
+    }
+
+    @Override
     public void addArtifact( Path sourceFile, Artifact destination ) throws IllegalArgumentException
     {