diff --git a/src/main/java/eu/omp/irap/vespa/epntapclient/gui/panels/RequestPanel.java b/src/main/java/eu/omp/irap/vespa/epntapclient/gui/panels/RequestPanel.java
index 73ccbc6..73633e0 100644
--- a/src/main/java/eu/omp/irap/vespa/epntapclient/gui/panels/RequestPanel.java
+++ b/src/main/java/eu/omp/irap/vespa/epntapclient/gui/panels/RequestPanel.java
@@ -57,6 +57,14 @@ public class RequestPanel extends JPanel {
 	 */
 	private List<ParamField> paramFields;
 
+	private TargetNameField targetNameField;
+
+	private DateRangeField timeRangeField;
+
+	private FloatRangeField spectralRangeField;
+
+	private DataProductTypeField dataProductTypeField;
+
 	/** The height of the buttons panel. */
 	private static final int BUTTON_PANEL_HEIGHT = 20;
 
@@ -84,12 +92,12 @@ public class RequestPanel extends JPanel {
 	 *
 	 * @return The JPanel.
 	 */
-	private JPanel buildParamPanel() {
+	public JPanel buildParamPanel() {
 		paramFields = new ArrayList<>();
-		paramFields.add(new TargetNameField(viewListener, "target_name"));
-		paramFields.add(new DateRangeField(viewListener, "time_"));
-		paramFields.add(new FloatRangeField(viewListener, "spectral_range_"));
-		paramFields.add(new DataProductTypeField(viewListener, "dataproduct_type"));
+		paramFields.add(getTargetNameField());
+		paramFields.add(getTimeRangeField());
+		paramFields.add(getSpectralRangeField());
+		paramFields.add(getDataProductTypeField());
 		JPanel paramPanel = new JPanel();
 		paramPanel.setLayout(new BoxLayout(paramPanel, BoxLayout.Y_AXIS));
 		paramPanel.setBorder(BorderFactory.createTitledBorder("Query parameters"));
@@ -102,6 +110,50 @@ public class RequestPanel extends JPanel {
 	}
 
 	/**
+	 * @return the data product field
+	 */
+	public DataProductTypeField getDataProductTypeField() {
+		if(dataProductTypeField == null){
+			dataProductTypeField = new DataProductTypeField(viewListener, "dataproduct_type");
+		}
+		
+		return dataProductTypeField;
+	}
+
+	/**
+	 * @return the spectral range field
+	 */
+	public FloatRangeField getSpectralRangeField() {
+		if (spectralRangeField == null){
+			spectralRangeField = new FloatRangeField(viewListener, "spectral_range_");
+		}
+		
+		return spectralRangeField;
+	}
+
+	/**
+	 * @return the time range field
+	 */
+	public DateRangeField getTimeRangeField() {
+		if (timeRangeField == null){
+			timeRangeField = new DateRangeField(viewListener, "time_");
+		}
+		
+		return timeRangeField;
+	}
+
+	/**
+	 * @return the target name field
+	 */
+	public TargetNameField getTargetNameField() {
+		if(targetNameField == null){
+			targetNameField = new TargetNameField(viewListener, "target_name");
+		}
+		
+		return targetNameField;
+	}
+
+	/**
 	 * Build a JPanel containing a text-area where the query is displayed.
 	 *
 	 * @return The JPanel.
--
libgit2 0.21.2