Refactor: don't reuse JAXB objects for internal configuration; create a Configuration interface.

src/main/java/de/kosit/validationtool/impl/ResolvingMode.java

@@ -0,0 +1,45 @@
+package de.kosit.validationtool.impl;
+
+import java.net.URI;
+
+import javax.xml.transform.URIResolver;
+
+import org.apache.commons.lang3.NotImplementedException;
+
+/**
+ * Defines how artefacts are resolved internally.
+ * 
+ * @author Andreas Penski
+ */
+public enum ResolvingMode {
+
+    /**
+     * Resolving using only the configured content repository. No furthing resolving allowed. This
+     */
+    STRICT_RELATIVE {
+
+        @Override
+        public URI resolve(final URI source, final URI repository) {
+            return RelativeUriResolver.resolve(source, repository);
+        }
+
+        @Override
+        public URIResolver createResolver(final URI repository) {
+            return new RelativeUriResolver(repository);
+        }
+    },
+
+    STRICT_LOCAL,
+
+    JDK_SUPPORTED,
+
+    CUSTOM;
+
+    public URI resolve(final URI source, final URI repository) {
+        throw new NotImplementedException("Not yet implemented");
+    }
+
+    public URIResolver createResolver(final URI repository) {
+        throw new NotImplementedException("Not yet implemented");
+    }
+}