diff --git a/src/main/java/eu/omp/irap/vespa/epntapclient/view/ParamField.java b/src/main/java/eu/omp/irap/vespa/epntapclient/view/ParamField.java
new file mode 100644
index 0000000..1917476
--- /dev/null
+++ b/src/main/java/eu/omp/irap/vespa/epntapclient/view/ParamField.java
@@ -0,0 +1,256 @@
+package eu.omp.irap.vespa.epntapclient.view;
+
+import java.awt.Color;
+import java.awt.Dimension;
+import java.beans.PropertyChangeEvent;
+import java.text.DateFormat;
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Locale;
+import java.util.Objects;
+
+import javax.swing.BoxLayout;
+import javax.swing.JLabel;
+import javax.swing.JPanel;
+import javax.swing.JTextField;
+import javax.swing.SwingUtilities;
+import javax.swing.event.ChangeEvent;
+import javax.swing.event.ChangeListener;
+import javax.swing.event.DocumentEvent;
+import javax.swing.event.DocumentListener;
+import javax.swing.text.Document;
+import javax.swing.text.JTextComponent;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+public abstract class ParamField extends JPanel {
+
+	/** The logger for this class. */
+	private static final Logger logger = LogManager.getLogger(ParamField.class);
+
+	private static final String DATE_FORMAT = "dd/MM/yyyy";
+	private static final String DATE_REGEX = "(^(((0[1-9]|1[0-9]|2[0-8])[\\/](0[1-9]|1[012]))|((29|30|31)[\\/](0[13578]|1[02]))|((29|30)[\\/](0[4,6,9]|11)))[\\/](19|[2-9][0-9])\\d\\d$)|(^29[\\/]02[\\/](19|[2-9][0-9])(00|04|08|12|16|20|24|28|32|36|40|44|48|52|56|60|64|68|72|76|80|84|88|92|96)$)";
+
+	private static final String MIN_SUFFIX = "min";
+	private static final String MAX_SUFFIX = "max";
+
+	protected static RequestView requestView;
+	protected String paramName;
+
+	public ParamField(RequestView requestView, String paramName) {
+		super();
+		this.setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
+		String strLabel = paramName.replaceAll("_", " ").trim();
+		JLabel label = new JLabel(strLabel.substring(0, 1).toUpperCase() + strLabel.substring(1));
+		label.setPreferredSize(new Dimension(140, 15));
+		this.add(label);
+		// TODO: Add tooltip text based on rr.table_column.column_description
+		this.requestView = requestView;
+		this.paramName = paramName;
+	}
+
+	public static class StringField extends ParamField {
+		StringField(RequestView requestView, String paramName) {
+			super(requestView, paramName);
+			JTextField field = new JTextField();
+			addChangeListener(field, e -> onUpdate(field));
+			this.add(field);
+		}
+
+		private void onUpdate(JTextField field) {
+			if ("".equals(field.getText())) {
+				requestView.updateParam(paramName, null);
+			} else {
+				requestView.updateParam(paramName, field.getText());
+			}
+		}
+	}
+
+	public static class FloatField extends ParamField {
+		FloatField(RequestView requestView, String paramName) {
+			super(requestView, paramName);
+			JTextField field = new JTextField();
+			addChangeListener(field, e -> onUpdate(field));
+			this.add(field);
+		}
+
+		private void onUpdate(JTextField field) {
+			if ("".equals(field.getText())) {
+				field.setBackground(Color.WHITE);
+				requestView.updateParam(paramName, null);
+			} else {
+				try {
+					requestView.updateParam(paramName, Float.parseFloat(field.getText()));
+					field.setBackground(Color.WHITE);
+				} catch (NumberFormatException e) {
+					field.setBackground(Color.PINK);
+				}
+			}
+		}
+	}
+
+	public static class DateRangeField extends ParamField {
+		DateRangeField(RequestView requestView, String paramName) {
+			super(requestView, paramName);
+			JTextField fieldMin = new JTextField();
+			addChangeListener(fieldMin, e -> onUpdate(fieldMin, MIN_SUFFIX));
+			this.add(fieldMin);
+
+			JTextField fieldMax = new JTextField();
+			addChangeListener(fieldMax, e -> onUpdate(fieldMax, MAX_SUFFIX));
+			this.add(fieldMax);
+		}
+
+		private void onUpdate(JTextField field, String suffix) {
+			DateFormat df = new SimpleDateFormat(DATE_FORMAT, Locale.ENGLISH);
+			if ("".equals(field.getText())) {
+				field.setBackground(Color.WHITE);
+				requestView.updateParam(paramName + suffix, null);
+			} else if (field.getText().matches(DATE_REGEX)) {
+				try {
+					long date = df.parse(field.getText()).getTime();
+					date = (Math.round((date / 86400000.0) + 2440587.5)); // to JD
+					requestView.updateParam(paramName + suffix, date);
+					field.setBackground(Color.WHITE);
+				} catch (ParseException e) {
+					field.setBackground(Color.PINK);
+				}
+				// TODO: check if date min < date max
+			} else {
+				field.setBackground(Color.PINK);
+			}
+		}
+	}
+
+	public static class FloatRangeField extends ParamField {
+		JTextField fieldMin;
+		JTextField fieldMax;
+
+		FloatRangeField(RequestView requestView, String paramName) {
+			super(requestView, paramName);
+			fieldMin = new JTextField();
+			addChangeListener(fieldMin, e -> onUpdate(fieldMin, MIN_SUFFIX));
+			this.add(fieldMin);
+
+			fieldMax = new JTextField();
+			addChangeListener(fieldMax, e -> onUpdate(fieldMax, MAX_SUFFIX));
+			this.add(fieldMax);
+		}
+
+		private void onUpdate(JTextField field, String suffix) {
+			if ("".equals(field.getText())) {
+				field.setBackground(Color.WHITE);
+				requestView.updateParam(paramName + suffix, null);
+			} else {
+				try {
+					requestView.updateParam(paramName + suffix, Float.parseFloat(field.getText()));
+					field.setBackground(Color.WHITE);
+				} catch (NumberFormatException e) {
+					field.setBackground(Color.PINK);
+				}
+			}
+		}
+	}
+
+	public static class TargetNameField extends ParamField {
+		TargetNameField(RequestView requestView, String paramName) {
+			super(requestView, paramName);
+			JTextField field = new JTextField();
+			addChangeListener(field, e -> onUpdate(field));
+			this.add(field);
+		}
+
+		private void onUpdate(JTextField field) {
+			// TODO: add resolver
+			if ("".equals(field.getText())) {
+				requestView.updateParam(paramName, null);
+			} else {
+				requestView.updateParam(paramName, field.getText());
+			}
+		}
+	}
+
+	public static class DataProductTypeField extends ParamField {
+		DataProductTypeField(RequestView requestView, String paramName) {
+			super(requestView, paramName);
+			JTextField field = new JTextField();
+			// TODO: listbox with enumerated values instead of JTextField
+			addChangeListener(field, e -> onUpdate(field));
+			this.add(field);
+		}
+
+		private void onUpdate(JTextField field) {
+			if ("".equals(field.getText())) {
+				requestView.updateParam(paramName, null);
+			} else {
+				requestView.updateParam(paramName, field.getText());
+			}
+		}
+	}
+
+	public static class TargetClassField extends ParamField {
+		TargetClassField(RequestView requestView, String paramName) {
+			super(requestView, paramName);
+			JTextField field = new JTextField();
+			// TODO: listbox with enumerated values instead of JTextField
+			addChangeListener(field, e -> onUpdate(field));
+			this.add(field);
+		}
+
+		private void onUpdate(JTextField field) {
+			if ("".equals(field.getText())) {
+				requestView.updateParam(paramName, null);
+			} else {
+				requestView.updateParam(paramName, field.getText());
+			}
+		}
+	}
+
+	// public class EnumParamField extends ParamField {
+	// EnumParamField() {
+	// super();
+	// }
+	// }
+
+	public static void addChangeListener(JTextComponent text, ChangeListener changeListener) {
+		Objects.requireNonNull(text);
+		Objects.requireNonNull(changeListener);
+		DocumentListener dl = new DocumentListener() {
+			private int lastChange = 0, lastNotifiedChange = 0;
+
+			@Override
+			public void insertUpdate(DocumentEvent e) {
+				changedUpdate(e);
+			}
+
+			@Override
+			public void removeUpdate(DocumentEvent e) {
+				changedUpdate(e);
+			}
+
+			@Override
+			public void changedUpdate(DocumentEvent e) {
+				lastChange++;
+				SwingUtilities.invokeLater(() -> {
+					if (lastNotifiedChange != lastChange) {
+						lastNotifiedChange = lastChange;
+						changeListener.stateChanged(new ChangeEvent(text));
+					}
+				});
+			}
+		};
+		text.addPropertyChangeListener("document", (PropertyChangeEvent e) -> {
+			Document d1 = (Document) e.getOldValue();
+			Document d2 = (Document) e.getNewValue();
+			if (d1 != null)
+				d1.removeDocumentListener(dl);
+			if (d2 != null)
+				d2.addDocumentListener(dl);
+			dl.changedUpdate(null);
+		});
+		Document d = text.getDocument();
+		if (d != null)
+			d.addDocumentListener(dl);
+	}
+}
\ No newline at end of file
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