diff --git a/core/src/net/sf/openrocket/database/ComponentPresetDatabase.java b/core/src/net/sf/openrocket/database/ComponentPresetDatabase.java
index bb2fae2b9..2945d3640 100644
--- a/core/src/net/sf/openrocket/database/ComponentPresetDatabase.java
+++ b/core/src/net/sf/openrocket/database/ComponentPresetDatabase.java
@@ -117,7 +117,7 @@ public abstract class ComponentPresetDatabase extends Database<ComponentPreset>
 	@Override
 	public List<ComponentPreset> listForTypes( List<ComponentPreset.Type> types ) {
 		blockUntilLoaded();
-		return listForTypes( (ComponentPreset.Type[]) types.toArray() );
+		return listForTypes( types.toArray(new ComponentPreset.Type[types.size()]) );
 	}
 
 	@Override
diff --git a/core/src/net/sf/openrocket/file/openrocket/savers/RocketSaver.java b/core/src/net/sf/openrocket/file/openrocket/savers/RocketSaver.java
index be7c52af8..4f46a663c 100644
--- a/core/src/net/sf/openrocket/file/openrocket/savers/RocketSaver.java
+++ b/core/src/net/sf/openrocket/file/openrocket/savers/RocketSaver.java
@@ -49,7 +49,7 @@ public class RocketSaver extends RocketComponentSaver {
 			if (id.equals(defId))
 				str += " default=\"true\"";
 			
-			if (rocket.getMotorConfigurationName(id) == "") {
+			if (rocket.getMotorConfigurationName(id).isEmpty()) {
 				str += "/>";
 			} else {
 				str += "><name>" + net.sf.openrocket.file.RocketSaver.escapeXML(rocket.getMotorConfigurationName(id))
diff --git a/core/src/net/sf/openrocket/gui/adaptors/BooleanModel.java b/core/src/net/sf/openrocket/gui/adaptors/BooleanModel.java
index a2f95ed3c..ded950592 100644
--- a/core/src/net/sf/openrocket/gui/adaptors/BooleanModel.java
+++ b/core/src/net/sf/openrocket/gui/adaptors/BooleanModel.java
@@ -6,6 +6,7 @@ import java.beans.PropertyChangeListener;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.EventObject;
 import java.util.List;
 
@@ -299,7 +300,7 @@ public class BooleanModel extends AbstractAction implements StateChangeListener,
 		
 		PropertyChangeListener[] listeners = this.getPropertyChangeListeners();
 		if (listeners.length > 0) {
-			log.warn("Invalidating " + this + " while still having listeners " + listeners);
+			log.warn("Invalidating " + this + " while still having listeners " + Arrays.toString(listeners));
 			for (PropertyChangeListener l : listeners) {
 				this.removePropertyChangeListener(l);
 			}
diff --git a/core/src/net/sf/openrocket/gui/scalefigure/RocketPanel.java b/core/src/net/sf/openrocket/gui/scalefigure/RocketPanel.java
index 2cef70809..fccad22c8 100644
--- a/core/src/net/sf/openrocket/gui/scalefigure/RocketPanel.java
+++ b/core/src/net/sf/openrocket/gui/scalefigure/RocketPanel.java
@@ -670,7 +670,7 @@ public class RocketPanel extends JPanel implements TreeSelectionListener, Change
 
 		// Check whether data is already up to date
 		if (flightDataFunctionalID == configuration.getRocket().getFunctionalModID() &&
-				flightDataMotorID == configuration.getMotorConfigurationID()) {
+				flightDataMotorID.equals(configuration.getMotorConfigurationID())) {
 			return;
 		}