Fix #308

xstream/src/java/com/thoughtworks/xstream/XStream.java

@@ -101,6 +101,7 @@
 import java.util.UUID;
 import java.util.Vector;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.regex.Pattern;
 
 import com.thoughtworks.xstream.converters.ConversionException;
@@ -141,6 +142,7 @@
 import com.thoughtworks.xstream.converters.enums.EnumConverter;
 import com.thoughtworks.xstream.converters.enums.EnumMapConverter;
 import com.thoughtworks.xstream.converters.enums.EnumSetConverter;
+import com.thoughtworks.xstream.converters.extended.AtomicBooleanConverter;
 import com.thoughtworks.xstream.converters.extended.CharsetConverter;
 import com.thoughtworks.xstream.converters.extended.ColorConverter;
 import com.thoughtworks.xstream.converters.extended.CurrencyConverter;
@@ -710,7 +712,7 @@ protected void setupSecurity() {
         allowTypeHierarchy(Path.class);
 
         final Set<Class<?>> types = new HashSet<>();
-        types.addAll(Arrays.<Class<?>>asList(BitSet.class, Charset.class, Class.class, Currency.class, Date.class,
+        types.addAll(Arrays.<Class<?>>asList(AtomicBoolean.class, BitSet.class, Charset.class, Class.class, Currency.class, Date.class,
             DecimalFormatSymbols.class, File.class, Locale.class, Object.class, Pattern.class, StackTraceElement.class,
             String.class, StringBuffer.class, StringBuilder.class, URL.class, URI.class, UUID.class));
         if (JVM.isSQLAvailable()) {
@@ -996,6 +998,7 @@ protected void setupConverters() {
         registerConverter(new JavaMethodConverter(classLoaderReference), PRIORITY_NORMAL);
         registerConverter(new JavaFieldConverter(classLoaderReference), PRIORITY_NORMAL);
         registerConverter(new LambdaConverter(mapper, reflectionProvider, classLoaderReference), PRIORITY_NORMAL);
+        registerConverter(new AtomicBooleanConverter(), PRIORITY_NORMAL);
 
         if (JVM.isAWTAvailable()) {
             registerConverter(new FontConverter(mapper), PRIORITY_NORMAL);

xstream/src/java/com/thoughtworks/xstream/converters/extended/AtomicBooleanConverter.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2022 XStream Committers.
+ * All rights reserved.
+ *
+ * The software in this package is published under the terms of the BSD
+ * style license a copy of which has been included with this distribution in
+ * the LICENSE.txt file.
+ *
+ * Created on 9 September 2022 by Basil Crow.
+ */
+package com.thoughtworks.xstream.converters.extended;
+
+import com.thoughtworks.xstream.converters.Converter;
+import com.thoughtworks.xstream.converters.MarshallingContext;
+import com.thoughtworks.xstream.converters.SingleValueConverterWrapper;
+import com.thoughtworks.xstream.converters.UnmarshallingContext;
+import com.thoughtworks.xstream.converters.basic.BooleanConverter;
+import com.thoughtworks.xstream.io.HierarchicalStreamReader;
+import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/** Converts an {@link AtomicBoolean}. */
+public class AtomicBooleanConverter implements Converter {
+
+    @Override
+    public boolean canConvert(Class<?> type) {
+        return type != null && AtomicBoolean.class.isAssignableFrom(type);
+    }
+
+    @Override
+    public void marshal(
+            Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
+        final AtomicBoolean atomicBoolean = (AtomicBoolean) source;
+        writer.startNode("value");
+        context.convertAnother(
+                atomicBoolean.get(), new SingleValueConverterWrapper(BooleanConverter.BINARY));
+        writer.endNode();
+    }
+
+    @Override
+    public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
+        reader.moveDown();
+        Object item =
+                context.convertAnother(
+                        null,
+                        Boolean.class,
+                        new SingleValueConverterWrapper(BooleanConverter.BINARY));
+        boolean value = item instanceof Boolean ? ((Boolean) item).booleanValue() : false;
+        reader.moveUp();
+        return new AtomicBoolean(value);
+    }
+}