diff --git a/src/main/java/com/github/fge/jsonschema/processors/data/FullData.java b/src/main/java/com/github/fge/jsonschema/processors/data/FullData.java
index 09ecd12c0..6018b1874 100644
--- a/src/main/java/com/github/fge/jsonschema/processors/data/FullData.java
+++ b/src/main/java/com/github/fge/jsonschema/processors/data/FullData.java
@@ -20,12 +20,18 @@
 package com.github.fge.jsonschema.processors.data;
 
 
+import com.github.fge.jsonschema.core.ref.JsonRef;
 import com.github.fge.jsonschema.core.report.MessageProvider;
 import com.github.fge.jsonschema.core.report.ProcessingMessage;
 import com.github.fge.jsonschema.core.tree.JsonTree;
 import com.github.fge.jsonschema.core.tree.SchemaTree;
+import com.google.common.base.Function;
+import com.google.common.base.Preconditions;
+import com.google.common.collect.Iterables;
+import com.google.common.collect.Queues;
 
-import javax.annotation.concurrent.Immutable;
+import javax.annotation.ParametersAreNonnullByDefault;
+import java.util.Deque;
 
 /**
  * Validation data for a validation processor
@@ -41,19 +47,27 @@
  * <p>The {@link ProcessingMessage} template generated contains information
  * about both the schema and instance.</p>
  */
-@Immutable
+// TODO: rework, rename; nulls are badly handled, etc
+@ParametersAreNonnullByDefault
 public final class FullData
     implements MessageProvider
 {
-    private final SchemaTree schema;
-    private final JsonTree instance;
+    private SchemaTree schema;
+    private JsonTree instance;
     private final boolean deepCheck;
 
+    /*
+     * Deque of SchemaTrees we had to go through during validation of a
+     * particular instance/pointer pair; when the latter changes,the deque is
+     * emptied.
+     */
+    private final Deque<SchemaTree> schemaPath = Queues.newArrayDeque();
+
     public FullData(final SchemaTree schema, final JsonTree instance,
         final boolean deepCheck)
     {
-        this.schema = schema;
-        this.instance = instance;
+        this.schema = Preconditions.checkNotNull(schema);
+        this.instance = Preconditions.checkNotNull(instance);
         this.deepCheck = deepCheck;
     }
 
@@ -62,6 +76,11 @@ public FullData(final SchemaTree schema, final JsonTree instance)
         this(schema, instance, false);
     }
 
+    /**
+     * <b>UNUSED</b>
+     *
+     * @param schema the schema
+     */
     @Deprecated
     public FullData(final SchemaTree schema)
     {
@@ -83,6 +102,16 @@ public boolean isDeepCheck()
         return deepCheck;
     }
 
+    public void setSchema(final SchemaTree schema)
+    {
+        this.schema = Preconditions.checkNotNull(schema);
+    }
+
+    public void setInstance(final JsonTree instance)
+    {
+        this.instance = Preconditions.checkNotNull(instance);
+    }
+
     /**
      * Return a new full data with another schema
      *
@@ -115,4 +144,18 @@ public ProcessingMessage newMessage()
             ret.put("instance", instance);
         return ret;
     }
+
+    public Iterable<JsonRef> getSchemaPath()
+    {
+        final Iterable<JsonRef> iterable = Iterables.transform(schemaPath,
+            new Function<SchemaTree, JsonRef>()
+            {
+                @Override
+                public JsonRef apply(final SchemaTree input)
+                {
+                    return input.getContext();
+                }
+            });
+        return Iterables.unmodifiableIterable(iterable);
+    }
 }