Prevent 'illegal reflective access' problems when instantiating XStream

pom.xml

@@ -673,6 +673,12 @@
         <version>${version.org.ops4j.pax.exam}</version>
         <scope>test</scope>
       </dependency>
+      <dependency>
+        <groupId>io.github.classgraph</groupId>
+        <artifactId>classgraph</artifactId>
+        <version>${version.io.github.classgraph}</version>
+        <scope>test</scope>
+      </dependency>
     </dependencies>
   </dependencyManagement>
 
@@ -1095,6 +1101,7 @@
     <version.commons.codec>1.11</version.commons.codec>
     <version.commons.lang3>3.8.1</version.commons.lang3>
     <version.hsqldb>2.2.8</version.hsqldb>
+    <version.io.github.classgraph>4.8.87</version.io.github.classgraph>
     <version.jakarta.activation.api>1.2.1</version.jakarta.activation.api>
     <version.jakarta.annotation.api>1.3.4</version.jakarta.annotation.api>
     <version.jakarta.xml.bind.api>2.3.2</version.jakarta.xml.bind.api>

xstream/pom.xml

@@ -137,6 +137,11 @@
       <artifactId>commons-lang3</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>io.github.classgraph</groupId>
+      <artifactId>classgraph</artifactId>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <build>

xstream/src/java/com/thoughtworks/xstream/converters/collections/PropertiesConverter.java

@@ -6,7 +6,7 @@
  * 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 23. February 2004 by Joe Walnes
  */
 package com.thoughtworks.xstream.converters.collections;
@@ -35,13 +35,12 @@
  * permissions for SecurityManager.checkPackageAccess, SecurityManager.checkMemberAccess(this, EnumSet.MEMBER) and
  * ReflectPermission("suppressAccessChecks").
  * </p>
- * 
+ *
  * @author Joe Walnes
  * @author Kevin Ring
  */
 public class PropertiesConverter implements Converter {
 
-    private final static Field defaultsField = Fields.locate(Properties.class, Properties.class, false);
     private final boolean sort;
 
     public PropertiesConverter() {
@@ -67,8 +66,8 @@ public void marshal(final Object source, final HierarchicalStreamWriter writer,
             writer.addAttribute("value", entry.getValue().toString());
             writer.endNode();
         }
-        if (defaultsField != null) {
-            final Properties defaults = (Properties)Fields.read(defaultsField, properties);
+        if (Reflections.defaultsField != null) {
+            final Properties defaults = (Properties)Fields.read(Reflections.defaultsField, properties);
             if (defaults != null) {
                 writer.startNode("defaults");
                 marshal(defaults, writer, context);
@@ -101,4 +100,7 @@ public Object unmarshal(final HierarchicalStreamReader reader, final Unmarshalli
         }
     }
 
+    private static class Reflections {
+        private final static Field defaultsField = Fields.locate(Properties.class, Properties.class, false);
+    }
 }

xstream/src/java/com/thoughtworks/xstream/converters/collections/TreeMapConverter.java

@@ -49,7 +49,6 @@ public int compare(final Comparable o1, final Comparable o2) {
 
     @SuppressWarnings("rawtypes")
     private final static Comparator NULL_MARKER = new NullComparator();
-    private final static Field comparatorField = Fields.locate(TreeMap.class, Comparator.class, false);
 
     public TreeMapConverter(final Mapper mapper) {
         super(mapper, TreeMap.class);
@@ -75,7 +74,7 @@ protected void marshalComparator(final Comparator<?> comparator, final Hierarchi
 
     @Override
     public Object unmarshal(final HierarchicalStreamReader reader, final UnmarshallingContext context) {
-        TreeMap<Object, Object> result = comparatorField != null ? new TreeMap<>() : null;
+        TreeMap<Object, Object> result = Reflections.comparatorField != null ? new TreeMap<>() : null;
         @SuppressWarnings("unchecked")
         final Comparator<Object> comparator = (Comparator<Object>)unmarshalComparator(reader, context, result);
         if (result == null) {
@@ -125,19 +124,23 @@ protected void populateTreeMap(final HierarchicalStreamReader reader, final Unma
         final TreeMap<Object, Object> typedResult = (TreeMap<Object, Object>)result;
         try {
             if (JVM.hasOptimizedTreeMapPutAll()) {
-                if (comparator != null && comparatorField != null) {
-                    comparatorField.set(result, comparator);
+                if (comparator != null && Reflections.comparatorField != null) {
+                    Reflections.comparatorField.set(result, comparator);
                 }
                 typedResult.putAll(sortedMap); // internal optimization will not call comparator
-            } else if (comparatorField != null) {
-                comparatorField.set(result, sortedMap.comparator());
+            } else if (Reflections.comparatorField != null) {
+                Reflections.comparatorField.set(result, sortedMap.comparator());
                 typedResult.putAll(sortedMap); // "sort" by index
-                comparatorField.set(result, comparator);
+                Reflections.comparatorField.set(result, comparator);
             } else {
                 typedResult.putAll(sortedMap); // will use comparator for already sorted map
             }
         } catch (final IllegalAccessException e) {
             throw new ObjectAccessException("Cannot set comparator of TreeMap", e);
         }
     }
+
+    private static class Reflections {
+        private final static Field comparatorField = Fields.locate(TreeMap.class, Comparator.class, false);
+    }
 }

xstream/src/java/com/thoughtworks/xstream/converters/collections/TreeSetConverter.java

@@ -42,43 +42,6 @@
  */
 public class TreeSetConverter extends CollectionConverter {
     private transient TreeMapConverter treeMapConverter;
-    private final static Field sortedMapField;
-    private final static Object constantValue;
-
-    static {
-        Object value = null;
-        sortedMapField = JVM.hasOptimizedTreeSetAddAll() ? Fields.locate(TreeSet.class, SortedMap.class, false) : null;
-        if (sortedMapField != null) {
-            final TreeSet<String> set = new TreeSet<>();
-            set.add("1");
-            set.add("2");
-
-            Map<String, Object> backingMap = null;
-            try {
-                @SuppressWarnings("unchecked")
-                final Map<String, Object> map = (Map<String, Object>)sortedMapField.get(set);
-                backingMap = map;
-            } catch (final IllegalAccessException e) {
-                // give up;
-            }
-            if (backingMap != null) {
-                final Object[] values = backingMap.values().toArray();
-                if (values[0] == values[1]) {
-                    value = values[0];
-                }
-            }
-        } else {
-            final Field valueField = Fields.locate(TreeSet.class, Object.class, true);
-            if (valueField != null) {
-                try {
-                    value = valueField.get(null);
-                } catch (final IllegalAccessException e) {
-                    // give up;
-                }
-            }
-        }
-        constantValue = value;
-    }
 
     public TreeSetConverter(final Mapper mapper) {
         super(mapper, TreeSet.class);
@@ -100,11 +63,11 @@ public Object unmarshal(final HierarchicalStreamReader reader, final Unmarshalli
         final boolean inFirstElement = unmarshalledComparator instanceof Mapper.Null;
         @SuppressWarnings("unchecked")
         final Comparator<Object> comparator = inFirstElement ? null : (Comparator<Object>)unmarshalledComparator;
-        if (sortedMapField != null) {
+        if (Reflections.sortedMapField != null) {
             final TreeSet<Object> possibleResult = comparator == null ? new TreeSet<>() : new TreeSet<>(comparator);
             Object backingMap = null;
             try {
-                backingMap = sortedMapField.get(possibleResult);
+                backingMap = Reflections.sortedMapField.get(possibleResult);
             } catch (final IllegalAccessException e) {
                 throw new ObjectAccessException("Cannot get backing map of TreeSet", e);
             }
@@ -146,7 +109,8 @@ protected void populateMap(final HierarchicalStreamReader reader, final Unmarsha
                     public boolean add(final Object object) {
                         @SuppressWarnings("unchecked")
                         final Map<Object, Object> collectionTarget = (Map<Object, Object>)target;
-                        return collectionTarget.put(object, constantValue != null ? constantValue : object) != null;
+                        return collectionTarget.put(
+                                object, Reflections.constantValue != null ? Reflections.constantValue : object) != null;
                     }
 
                     @Override
@@ -173,4 +137,46 @@ protected void putCurrentEntryIntoMap(final HierarchicalStreamReader reader,
         };
         return this;
     }
+
+    private static class Reflections {
+
+        private final static Field sortedMapField;
+        private final static Object constantValue;
+
+        static {
+            Object value = null;
+            sortedMapField = JVM.hasOptimizedTreeSetAddAll()
+                    ? Fields.locate(TreeSet.class, SortedMap.class, false) : null;
+            if (sortedMapField != null) {
+                final TreeSet<String> set = new TreeSet<>();
+                set.add("1");
+                set.add("2");
+
+                Map<String, Object> backingMap = null;
+                try {
+                    @SuppressWarnings("unchecked")
+                    final Map<String, Object> map = (Map<String, Object>)sortedMapField.get(set);
+                    backingMap = map;
+                } catch (final IllegalAccessException e) {
+                    // give up;
+                }
+                if (backingMap != null) {
+                    final Object[] values = backingMap.values().toArray();
+                    if (values[0] == values[1]) {
+                        value = values[0];
+                    }
+                }
+            } else {
+                final Field valueField = Fields.locate(TreeSet.class, Object.class, true);
+                if (valueField != null) {
+                    try {
+                        value = valueField.get(null);
+                    } catch (final IllegalAccessException e) {
+                        // give up;
+                    }
+                }
+            }
+            constantValue = value;
+        }
+    }
 }

xstream/src/java/com/thoughtworks/xstream/converters/enums/EnumMapConverter.java

@@ -6,7 +6,7 @@
  * 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 06. April 2005 by Joe Walnes
  */
 
@@ -31,25 +31,24 @@
  * If a {@link SecurityManager} is set, the converter will only work with permissions for SecurityManager.checkPackageAccess,
  * SecurityManager.checkMemberAccess(this, EnumSet.MEMBER) and ReflectPermission("suppressAccessChecks").
  * </p>
- * 
+ *
  * @author Joe Walnes
  */
 public class EnumMapConverter extends MapConverter {
 
-    private final static Field typeField = Fields.locate(EnumMap.class, Class.class, false);
 
     public EnumMapConverter(final Mapper mapper) {
         super(mapper);
     }
 
     @Override
     public boolean canConvert(final Class<?> type) {
-        return typeField != null && type == EnumMap.class;
+        return type == EnumMap.class && Reflections.typeField != null;
     }
 
     @Override
     public void marshal(final Object source, final HierarchicalStreamWriter writer, final MarshallingContext context) {
-        final Class<?> type = (Class<?>)Fields.read(typeField, source);
+        final Class<?> type = (Class<?>)Fields.read(Reflections.typeField, source);
         final String attributeName = mapper().aliasForSystemAttribute("enum-type");
         if (attributeName != null) {
             writer.addAttribute(attributeName, mapper().serializedClass(type));
@@ -69,4 +68,8 @@ public Object unmarshal(final HierarchicalStreamReader reader, final Unmarshalli
         populateMap(reader, context, map);
         return map;
     }
+
+    private static class Reflections {
+        private final static Field typeField = Fields.locate(EnumMap.class, Class.class, false);
+    }
 }

xstream/src/java/com/thoughtworks/xstream/converters/enums/EnumSetConverter.java

@@ -6,7 +6,7 @@
  * 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 06. April 2005 by Joe Walnes
  */
 
@@ -31,13 +31,12 @@
  * If a SecurityManager is set, the converter will only work with permissions for SecurityManager.checkPackageAccess,
  * SecurityManager.checkMemberAccess(this, EnumSet.MEMBER) and ReflectPermission("suppressAccessChecks").
  * </p>
- * 
+ *
  * @author Joe Walnes
  * @author J&ouml;rg Schaible
  */
 public class EnumSetConverter implements Converter {
 
-    private final static Field typeField = Fields.locate(EnumSet.class, Class.class, false);
     private final Mapper mapper;
 
     public EnumSetConverter(final Mapper mapper) {
@@ -46,13 +45,13 @@ public EnumSetConverter(final Mapper mapper) {
 
     @Override
     public boolean canConvert(final Class<?> type) {
-        return typeField != null && type != null && EnumSet.class.isAssignableFrom(type);
+        return type != null && EnumSet.class.isAssignableFrom(type) && Reflections.typeField != null;
     }
 
     @Override
     public void marshal(final Object source, final HierarchicalStreamWriter writer, final MarshallingContext context) {
         final EnumSet<?> set = (EnumSet<?>)source;
-        final Class<?> enumTypeForSet = (Class<?>)Fields.read(typeField, set);
+        final Class<?> enumTypeForSet = (Class<?>)Fields.read(Reflections.typeField, set);
         final String attributeName = mapper.aliasForSystemAttribute("enum-type");
         if (attributeName != null) {
             writer.addAttribute(attributeName, mapper.serializedClass(enumTypeForSet));
@@ -99,4 +98,7 @@ private <T extends Enum<T>> EnumSet<T> create(final Class<T> type, final String
         return set;
     }
 
+    private static class Reflections {
+        private final static Field typeField = Fields.locate(EnumSet.class, Class.class, false);
+    }
 }