using XStream for XML serialization instead of JAXB

zmt.general/build.gradle
    added XStream as dependency
ParamsMenu, Launcher, DefaultParamsLoader,DefaultSimulationLooper
    adapted to XStream with improved exception handling
AbstractParamDefinition, AutoParams, AutoDefinition, FieldLocator
    adapted to XStream by changing annotations
ParamsUtil.java
    offers singleton XStream instance
Rotation2D.java
    added custom converter
AmountUtil.java
    replaced XmlAdapter with XStream converters for Amount and Unit types

src/main/java/de/zmt/util/AmountUtil.java

@@ -13,11 +13,14 @@ import javax.measure.quantity.Quantity;
 import javax.measure.unit.FixedDefaultUnitFormat;
 import javax.measure.unit.Unit;
 import javax.measure.unit.UnitFormat;
-import javax.xml.bind.annotation.adapters.XmlAdapter;
 
 import org.jscience.physics.amount.Amount;
 import org.jscience.physics.amount.AmountFormat;
 
+import com.thoughtworks.xstream.XStreamException;
+import com.thoughtworks.xstream.converters.Converter;
+import com.thoughtworks.xstream.converters.SingleValueConverter;
+
 import javolution.text.TypeFormat;
 
 /**
@@ -30,8 +33,8 @@ public abstract class AmountUtil {
     @SuppressWarnings("unused")
     private static final Logger logger = Logger.getLogger(AmountUtil.class.getName());
 
-    /** {@link AmountFormat} for display in MASON GUI. */
     public static final AmountFormat FORMAT = new SimpleAmountFormat();
+    private static final UnitFormat UNIT_FORMAT = new FixedDefaultUnitFormat();
     /**
      * 
      * @param unit
@@ -192,21 +195,54 @@ public abstract class AmountUtil {
     }
 
     /**
-     * {@link XmlAdapter} for (un)marshalling jScience {@link Amount}s.
+     * {@link Converter} for {@link Amount} to / from XML.
      * 
      * @author mey
+     *
+     */
+    public static class XmlAmountConverter implements SingleValueConverter {
+
+	@Override
+	public boolean canConvert(@SuppressWarnings("rawtypes") Class type) {
+	    return type.equals(Amount.class);
+	}
+
+	@Override
+	public String toString(Object obj) {
+	    return FORMAT.format((Amount<?>) obj).toString();
+	}
+
+	@Override
+	public Object fromString(String str) {
+	    return FORMAT.parse(str);
+	}
+
+    }
+
+    /**
+     * {@link Converter} for {@link Unit} to / from XML.
      * 
+     * @author mey
+     *
      */
-    public static class XmlAmountAdapter extends XmlAdapter<String, Amount<?>> {
+    public static class XmlUnitConverter implements SingleValueConverter {
+	@Override
+	public boolean canConvert(@SuppressWarnings("rawtypes") Class type) {
+	    return Unit.class.isAssignableFrom(type);
+	}
 
 	@Override
-	public Amount<?> unmarshal(String v) throws Exception {
-	    return FORMAT.parse(v);
+	public String toString(Object obj) {
+	    return UNIT_FORMAT.format(obj).toString();
 	}
 
 	@Override
-	public String marshal(Amount<?> v) throws Exception {
-	    return FORMAT.format(v).toString();
+	public Object fromString(String str) {
+	    try {
+		return UNIT_FORMAT.parseObject(str);
+	    } catch (ParseException e) {
+		throw new XStreamException(e);
+	    }
 	}
     }
 
@@ -218,8 +254,6 @@ public abstract class AmountUtil {
      *
      */
     private static class SimpleAmountFormat extends AmountFormat {
-	private static final UnitFormat UNIT_FORMAT = new FixedDefaultUnitFormat();
-
 	@Override
 	public Appendable format(Amount<?> obj, Appendable dest) throws IOException {
 	    if (obj.isExact()) {