Exception handler able to catch getter and setter exceptions

src/main/java/de/danielbechler/diff/BeanDiffer.java

@@ -17,6 +17,7 @@
 package de.danielbechler.diff;
 
 import de.danielbechler.diff.accessor.*;
+import de.danielbechler.diff.accessor.exception.ExceptionListener;
 import de.danielbechler.diff.introspect.*;
 import de.danielbechler.diff.node.*;
 import de.danielbechler.util.*;
@@ -34,11 +35,11 @@ final class BeanDiffer implements Differ<Node>
 	private BeanPropertyComparisonDelegator beanPropertyComparisonDelegator;
 	private DefaultNodeFactory defaultNodeFactory = new DefaultNodeFactory();
 
-	public BeanDiffer(final DifferDelegator delegator, final NodeInspector nodeInspector)
+	public BeanDiffer(final DifferDelegator delegator, final NodeInspector nodeInspector, final ExceptionListener exceptionListener)
 	{
 		Assert.notNull(delegator, "delegator");
 		Assert.notNull(nodeInspector, "configuration");
-		this.beanPropertyComparisonDelegator = new BeanPropertyComparisonDelegator(delegator, nodeInspector);
+		this.beanPropertyComparisonDelegator = new BeanPropertyComparisonDelegator(delegator, nodeInspector, exceptionListener);
 		this.nodeInspector = nodeInspector;
 	}
 

src/main/java/de/danielbechler/diff/BeanPropertyComparisonDelegator.java

@@ -17,6 +17,9 @@
 package de.danielbechler.diff;
 
 import de.danielbechler.diff.accessor.*;
+import de.danielbechler.diff.accessor.exception.ExceptionListener;
+import de.danielbechler.diff.accessor.exception.PropertyReadException;
+import de.danielbechler.diff.accessor.exception.PropertyWriteException;
 import de.danielbechler.diff.node.*;
 import de.danielbechler.util.*;
 
@@ -26,14 +29,17 @@ class BeanPropertyComparisonDelegator
 	private final DifferDelegator delegator;
 	private final NodeInspector nodeInspector;
 	private PropertyNodeFactory propertyNodeFactory = new PropertyNodeFactory();
+	private final ExceptionListener exceptionListener;
 
-	public BeanPropertyComparisonDelegator(final DifferDelegator delegator, final NodeInspector nodeInspector)
+	public BeanPropertyComparisonDelegator(final DifferDelegator delegator, final NodeInspector nodeInspector, final ExceptionListener exceptionListener)
 	{
 		Assert.notNull(delegator, "delegator");
 		Assert.notNull(nodeInspector, "nodeInspector");
+		Assert.notNull(exceptionListener, "exceptionListener");
 
 		this.delegator = delegator;
 		this.nodeInspector = nodeInspector;
+		this.exceptionListener = exceptionListener;
 	}
 
 	public Node compare(final Node beanNode, final Instances beanInstances, final Accessor propertyAccessor)
@@ -51,7 +57,13 @@ public Node compare(final Node beanNode, final Instances beanInstances, final Ac
 		}
 		else
 		{
-			return delegator.delegate(beanNode, beanInstances.access(propertyAccessor));
+			try {
+				return delegator.delegate(beanNode, beanInstances.access(propertyAccessor));
+			} catch(PropertyReadException e) {
+				return exceptionListener.onPropertyReadException(e, propertyNode);
+			} catch(PropertyWriteException e) {
+				return exceptionListener.onPropertyWriteException(e, propertyNode);
+			}
 		}
 	}
 

src/main/java/de/danielbechler/diff/DifferFactory.java

@@ -50,7 +50,7 @@ else if (Map.class.isAssignableFrom(type))
 		}
 		else
 		{
-			return new BeanDiffer(delegator, configuration);
+			return new BeanDiffer(delegator, configuration, configuration.getExceptionListener());
 		}
 	}
 

src/main/java/de/danielbechler/diff/accessor/PropertyAccessor.java

@@ -86,9 +86,7 @@ private void invokeWriteMethod(final Object target, final Object value)
 		}
 		catch (Exception e)
 		{
-			logFailedSet(value);
-
-			final PropertyWriteException ex = new PropertyWriteException(e);
+			final PropertyWriteException ex = new PropertyWriteException(e, value);
 			ex.setPropertyName(propertyName);
 			ex.setTargetType(getType());
 			throw ex;

src/main/java/de/danielbechler/diff/accessor/exception/DefaultExceptionListener.java

@@ -1,7 +1,9 @@
 package de.danielbechler.diff.accessor.exception;
 
-import de.danielbechler.diff.node.*;
-import org.slf4j.*;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import de.danielbechler.diff.node.Node;
 
 /**
  * Handler for recoverable exceptional states which logs the warning or info messages into log. The exception
@@ -19,4 +21,15 @@ public void onCircularReferenceException(final Node node)
 				+ "this instance along the current path.";
 		logger.warn(message, node.getPropertyPath());
 	}
-}
+
+	public Node onPropertyWriteException(final PropertyWriteException ex, final Node propertyNode)
+	{
+		logger.info("Couldn't set new value '{}' for property '{}'", ex.getNewValue(), ex.getPropertyName());
+		throw ex;
+	}
+
+	public Node onPropertyReadException(final PropertyReadException ex, final Node propertyNode)
+	{
+		throw ex;
+	}
+}

src/main/java/de/danielbechler/diff/accessor/exception/ExceptionListener.java

@@ -14,4 +14,26 @@ public interface ExceptionListener
 	 * @param node The node which has been detected to cause a circular reference.
 	 */
 	void onCircularReferenceException(Node node);
-}
+
+	/**
+	 * Called when PropertyWriteException happens.
+	 * 
+	 * @param e
+	 *            PropertyWriteException itself.
+	 * @param propertyNode
+	 *            Node of the property that we were unable to write to.
+	 * @return Resulting node.
+	 */
+	Node onPropertyWriteException(PropertyWriteException e, Node propertyNode);
+
+	/**
+	 * Called when PropertyReadException happens.
+	 * 
+	 * @param ex
+	 *            The PropertyReadException itself.
+	 * @param propertyNode
+	 *            Node of the property that we were unable to read.
+	 * @return Node as a result of wrong read.
+	 */
+	Node onPropertyReadException(PropertyReadException ex, Node propertyNode);
+}

src/main/java/de/danielbechler/diff/accessor/exception/PropertyWriteException.java

@@ -20,15 +20,22 @@
 public class PropertyWriteException extends PropertyException
 {
 	private static final long serialVersionUID = 1L;
+	private final Object newValue;
 
-	public PropertyWriteException(final Throwable cause)
+	public PropertyWriteException(final Throwable cause, final Object newValue)
 	{
 		super(cause);
+		this.newValue = newValue;
 	}
 
 	@Override
 	public String getMessage()
 	{
 		return "Error while invoking write method. ";
 	}
+
+	public Object getNewValue() 
+	{
+		return newValue;
+	}
 }

src/test/java/de/danielbechler/diff/BeanDifferShould.java

@@ -17,10 +17,12 @@
 package de.danielbechler.diff;
 
 import de.danielbechler.diff.accessor.*;
+import de.danielbechler.diff.accessor.exception.DefaultExceptionListener;
 import de.danielbechler.diff.introspect.*;
 import de.danielbechler.diff.mock.*;
 import de.danielbechler.diff.node.*;
 import de.danielbechler.diff.path.*;
+
 import org.mockito.Mock;
 import org.testng.annotations.*;
 
@@ -51,7 +53,7 @@ public void setUp()
 	{
 		initMocks(this);
 		configuration = new Configuration();
-		differ = new BeanDiffer(delegator, configuration);
+		differ = new BeanDiffer(delegator, configuration, configuration.getExceptionListener());
 		differ.setIntrospector(introspector);
 	}
 
@@ -165,12 +167,13 @@ public void compare_bean_via_introspection_and_delegate_comparison_of_properties
 
 		when(defaultNodeFactory.createNode(Node.ROOT, beanInstances)).thenReturn(beanNode);
 		when(configuration.isIntrospectible(beanNode)).thenReturn(true);
+		when(configuration.getExceptionListener()).thenReturn(new DefaultExceptionListener());
 		doReturn(beanType).when(beanInstances).getType();
 		when(introspector.introspect(beanType)).thenReturn(asList(propertyAccessor));
 		when(beanPropertyComparer.compare(beanNode, beanInstances, propertyAccessor)).thenReturn(propertyNode);
 		when(configuration.isReturnable(propertyNode)).thenReturn(true);
 
-		differ = new BeanDiffer(delegator, configuration);
+		differ = new BeanDiffer(delegator, configuration, configuration.getExceptionListener());
 		differ.setIntrospector(introspector);
 		differ.setBeanPropertyComparisonDelegator(beanPropertyComparer);
 		differ.setDefaultNodeFactory(defaultNodeFactory);
@@ -183,12 +186,12 @@ public void compare_bean_via_introspection_and_delegate_comparison_of_properties
 	@Test(expectedExceptions = IllegalArgumentException.class)
 	public void fail_construction_without_delegator()
 	{
-		new BeanDiffer(null, configuration);
+		new BeanDiffer(null, configuration, configuration.getExceptionListener());
 	}
 
 	@Test(expectedExceptions = IllegalArgumentException.class)
 	public void fail_construction_without_configuration()
 	{
-		new BeanDiffer(delegator, null);
+		new BeanDiffer(delegator, null, new DefaultExceptionListener());
 	}
 }

src/test/java/de/danielbechler/diff/BeanPropertyComparisonDelegatorShould.java

@@ -17,7 +17,9 @@
 package de.danielbechler.diff;
 
 import de.danielbechler.diff.accessor.*;
+import de.danielbechler.diff.accessor.exception.DefaultExceptionListener;
 import de.danielbechler.diff.node.*;
+
 import org.mockito.Mock;
 import org.testng.annotations.*;
 
@@ -42,8 +44,8 @@ public class BeanPropertyComparisonDelegatorShould
 	protected void setUp() throws Exception
 	{
 		initMocks(this);
-
-		beanPropertyComparisonDelegator = new BeanPropertyComparisonDelegator(delegator, configuration);
+		when(configuration.getExceptionListener()).thenReturn(new DefaultExceptionListener());
+		beanPropertyComparisonDelegator = new BeanPropertyComparisonDelegator(delegator, configuration, configuration.getExceptionListener());
 		beanPropertyComparisonDelegator.setPropertyNodeFactory(propertyNodeFactory);
 	}
 
@@ -94,13 +96,13 @@ public void delegate_property_comparison()
 	@Test(expectedExceptions = IllegalArgumentException.class)
 	public void fail_if_constructed_without_delegator()
 	{
-		new BeanPropertyComparisonDelegator(null, configuration);
+		new BeanPropertyComparisonDelegator(null, configuration, configuration.getExceptionListener());
 	}
 
 	@Test(expectedExceptions = IllegalArgumentException.class)
 	public void fail_if_constructed_without_configuration()
 	{
-		new BeanPropertyComparisonDelegator(delegator, null);
+		new BeanPropertyComparisonDelegator(delegator, null, new DefaultExceptionListener());
 	}
 
 	@Test(expectedExceptions = IllegalArgumentException.class)

src/test/java/de/danielbechler/diff/DifferFactoryShould.java

@@ -16,13 +16,16 @@
 
 package de.danielbechler.diff;
 
+import de.danielbechler.diff.accessor.exception.DefaultExceptionListener;
 import de.danielbechler.diff.mock.*;
+
 import org.mockito.Mock;
 import org.testng.annotations.*;
 
 import java.util.*;
 
 import static org.fest.assertions.api.Assertions.*;
+import static org.mockito.Mockito.when;
 import static org.mockito.MockitoAnnotations.*;
 
 /** @author Daniel Bechler */
@@ -38,6 +41,7 @@ public class DifferFactoryShould
 	public void initDifferFactory()
 	{
 		initMocks(this);
+		when(configuration.getExceptionListener()).thenReturn(new DefaultExceptionListener());
 		differFactory = new DifferFactory(configuration);
 	}