1 files changed, 117 insertions, 0 deletions
diff --git a/kamon-annotation/src/main/java/kamon/annotation/el/resolver/PrivateFieldELResolver.java b/kamon-annotation/src/main/java/kamon/annotation/el/resolver/PrivateFieldELResolver.java
new file mode 100644
index 00000000..df646942
--- /dev/null
+++ b/kamon-annotation/src/main/java/kamon/annotation/el/resolver/PrivateFieldELResolver.java
@@ -0,0 +1,117 @@
+/*
+ * =========================================================================================
+ * Copyright © 2013-2015 the kamon project <http://kamon.io/>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ * =========================================================================================
+ */
+
+package kamon.annotation.el.resolver;
+
+import java.beans.FeatureDescriptor;
+import java.lang.reflect.Field;
+import java.util.Iterator;
+import javax.el.ELContext;
+import javax.el.ELException;
+import javax.el.ELResolver;
+
+/**
+ * A custom {@link ELResolver} for mapping properties to public/private fields of the base object.
+ */
+public class PrivateFieldELResolver extends ELResolver {
+
+    @Override
+    public Object getValue(ELContext context, Object base, Object property) {
+        if (base == null) {
+            return null;
+        }
+        try {
+            Field field = getField(base, (String) property);
+            context.setPropertyResolved(true);
+            field.setAccessible(true);
+            return field.get(base);
+        } catch (NoSuchFieldException exc) {
+            context.setPropertyResolved(false);
+            return null;
+        } catch (Exception exc) {
+            throw new ELException(exc);
+        }
+    }
+
+    private Field getField(Object base, String property) throws NoSuchFieldException {
+        try {
+            return base.getClass().getDeclaredField(property);
+        } catch (SecurityException exc) {
+            throw new ELException(exc);
+        }
+    }
+
+    @Override
+    public Class<?> getType(ELContext context, Object base, Object property) {
+        if (base == null) {
+            return null;
+        }
+        try {
+            Field field = getField(base, (String) property);
+            if (field != null) {
+                context.setPropertyResolved(true);
+                return field.getType();
+            } else {
+                return null;
+            }
+        } catch (NoSuchFieldException exc) {
+            context.setPropertyResolved(false);
+            return null;
+        }
+    }
+
+    @Override
+    public void setValue(ELContext context, Object base, Object property, Object value) {
+        if (base == null) {
+            return;
+        }
+        try {
+            context.setPropertyResolved(true);
+            getField(base, (String) property).set(base, value);
+        } catch (NoSuchFieldException exc) {
+            context.setPropertyResolved(false);
+        } catch (Exception exc) {
+            throw new ELException(exc);
+        }
+    }
+
+    @Override
+    public boolean isReadOnly(ELContext context, Object base, Object property) {
+        if (base == null) {
+            return true;
+        }
+        try {
+            Field field = getField(base, (String) property);
+            if (field != null) {
+                context.setPropertyResolved(true);
+                return !field.isAccessible();
+            }
+        } catch (NoSuchFieldException exc) {
+            context.setPropertyResolved(false);
+        }
+        return false;
+    }
+
+    @Override
+    public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base) {
+        return null;
+    }
+
+    @Override
+    public Class<?> getCommonPropertyType(ELContext context, Object base) {
+        return String.class;
+    }
+}
+\ No newline at end of file