4 files changed, 12 insertions, 4 deletions
diff --git a/main/src/cgeo/geocaching/connector/capability/ISearchByCenter.java b/main/src/cgeo/geocaching/connector/capability/ISearchByCenter.java
index 91dd094..94e31cd 100644
--- a/main/src/cgeo/geocaching/connector/capability/ISearchByCenter.java
+++ b/main/src/cgeo/geocaching/connector/capability/ISearchByCenter.java
@@ -4,10 +4,12 @@ import cgeo.geocaching.SearchResult;
 import cgeo.geocaching.connector.IConnector;
 import cgeo.geocaching.geopoint.Geopoint;
 
+import org.eclipse.jdt.annotation.NonNull;
+
 /**
  * connector capability for online searching caches around a center coordinate, sorted by distance
  *
  */
 public interface ISearchByCenter extends IConnector {
-    public SearchResult searchByCenter(final Geopoint center);
+    public SearchResult searchByCenter(final @NonNull Geopoint center);
 }
diff --git a/main/src/cgeo/geocaching/connector/capability/ISearchByGeocode.java b/main/src/cgeo/geocaching/connector/capability/ISearchByGeocode.java
index 4c16049..7abc235 100644
--- a/main/src/cgeo/geocaching/connector/capability/ISearchByGeocode.java
+++ b/main/src/cgeo/geocaching/connector/capability/ISearchByGeocode.java
@@ -4,10 +4,12 @@ import cgeo.geocaching.SearchResult;
 import cgeo.geocaching.connector.IConnector;
 import cgeo.geocaching.utils.CancellableHandler;
 
+import org.eclipse.jdt.annotation.Nullable;
+
 /**
  * connector capability of searching online for a cache by geocode
  *
  */
 public interface ISearchByGeocode extends IConnector {
-    public SearchResult searchByGeocode(final String geocode, final String guid, final CancellableHandler handler);
+    public SearchResult searchByGeocode(final @Nullable String geocode, final @Nullable String guid, final CancellableHandler handler);
 }
diff --git a/main/src/cgeo/geocaching/connector/capability/ISearchByKeyword.java b/main/src/cgeo/geocaching/connector/capability/ISearchByKeyword.java
index 09b2423..07cb7b3 100644
--- a/main/src/cgeo/geocaching/connector/capability/ISearchByKeyword.java
+++ b/main/src/cgeo/geocaching/connector/capability/ISearchByKeyword.java
@@ -3,10 +3,12 @@ package cgeo.geocaching.connector.capability;
 import cgeo.geocaching.SearchResult;
 import cgeo.geocaching.connector.IConnector;
 
+import org.eclipse.jdt.annotation.NonNull;
+
 /**
  * connector capability of searching online for a cache by name
  *
  */
 public interface ISearchByKeyword extends IConnector {
-    public SearchResult searchByName(final String name);
+    public SearchResult searchByName(final @NonNull String name);
 }
diff --git a/main/src/cgeo/geocaching/connector/capability/ISearchByViewPort.java b/main/src/cgeo/geocaching/connector/capability/ISearchByViewPort.java
index 4954017..c04e9ed 100644
--- a/main/src/cgeo/geocaching/connector/capability/ISearchByViewPort.java
+++ b/main/src/cgeo/geocaching/connector/capability/ISearchByViewPort.java
@@ -4,6 +4,8 @@ import cgeo.geocaching.SearchResult;
 import cgeo.geocaching.connector.IConnector;
 import cgeo.geocaching.geopoint.Viewport;
 
+import org.eclipse.jdt.annotation.NonNull;
+
 public interface ISearchByViewPort extends IConnector {
-    public SearchResult searchByViewport(final Viewport viewport, final String[] tokens);
+    public SearchResult searchByViewport(final @NonNull Viewport viewport, final String[] tokens);
 }