com.interface21.beans.BeanWrapperImpl.java Source code

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/*
 * The Spring Framework is published under the terms
 * of the Apache Software License.
 */

package com.interface21.beans;

import java.beans.IndexedPropertyDescriptor;
import java.beans.MethodDescriptor;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.beans.PropertyDescriptor;
import java.beans.PropertyEditor;
import java.beans.PropertyEditorManager;
import java.beans.PropertyVetoException;
import java.beans.VetoableChangeListener;
import java.beans.VetoableChangeSupport;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.interface21.beans.propertyeditors.ClassEditor;
import com.interface21.beans.propertyeditors.LocaleEditor;
import com.interface21.beans.propertyeditors.PropertiesEditor;
import com.interface21.beans.propertyeditors.PropertyValuesEditor;
import com.interface21.beans.propertyeditors.StringArrayPropertyEditor;

/**
 * Default implementation of the BeanWrapper interface that should be sufficient
 * for all normal uses. Caches introspection results for efficiency.
 *
 * <p>Note: this class never tries to load a class by name, as this can pose
 * class loading problems in J2EE applications with multiple deployment modules.
 * For example, loading a class by name won't work in some application servers
 * if the class is used in a WAR but was loaded by the EJB class loader and the
 * class to be loaded is in the WAR. (This class would use the EJB classloader,
 * which couldn't see the required class.) We don't attempt to solve such problems
 * by obtaining the classloader at runtime, because this violates the EJB
 * programming restrictions.
 *
 * <p>Note: Regards property editors in com.interface21.beans.propertyeditors.
 * Also explictly register the default ones to care for JREs that do not use
 * the thread context class loader for editor search paths.
 * Applications can either use a standard PropertyEditorManager to register a
 * custom editor before using a BeanWrapperImpl instance, or call the instance's
 * registerCustomEditor method to register an editor for the particular instance.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @since 15 April 2001
 * @version $Id: BeanWrapperImpl.java,v 1.13 2003/07/31 18:44:56 jhoeller Exp $
 * @see #registerCustomEditor
 * @see java.beans.PropertyEditorManager
 */
public class BeanWrapperImpl implements BeanWrapper {

    /** Should JavaBeans event propagation be enabled by default? */
    public static final boolean DEFAULT_EVENT_PROPAGATION_ENABLED = false;

    /**
     * We'll create a lot of these objects, so we don't want a new logger every time.
     */
    private static final Log logger = LogFactory.getLog(BeanWrapperImpl.class);

    private static final Map defaultEditors = new HashMap();

    static {
        // install default property editors
        try {
            // this one can't apply the <ClassName>Editor naming pattern
            PropertyEditorManager.registerEditor(String[].class, StringArrayPropertyEditor.class);
            // register all editors in our standard package
            PropertyEditorManager.setEditorSearchPath(
                    new String[] { "sun.beans.editors", "com.interface21.beans.propertyeditors" });
        } catch (SecurityException ex) {
            // e.g. in applets -> log and proceed
            logger.warn("Cannot register property editors with PropertyEditorManager", ex);
        }

        // register default editors in this class, for restricted environments
        // where the above threw a SecurityException, and for JDKs that don't
        // use the thread context class loader for property editor lookup
        defaultEditors.put(String[].class, new StringArrayPropertyEditor());
        defaultEditors.put(PropertyValues.class, new PropertyValuesEditor());
        defaultEditors.put(Properties.class, new PropertiesEditor());
        defaultEditors.put(Class.class, new ClassEditor());
        defaultEditors.put(Locale.class, new LocaleEditor());
    }

    //---------------------------------------------------------------------
    // Instance data
    //---------------------------------------------------------------------

    /** The wrapped object */
    private Object object;

    /**
     * Cached introspections results for this object, to prevent encountering the cost
     * of JavaBeans introspection every time.
     * */
    private CachedIntrospectionResults cachedIntrospectionResults;

    /** Standard java.beans helper object used to propagate events */
    private VetoableChangeSupport vetoableChangeSupport;

    /** Standard java.beans helper object used to propagate events */
    private PropertyChangeSupport propertyChangeSupport;

    /** Should we propagate events to listeners? */
    private boolean eventPropagationEnabled = DEFAULT_EVENT_PROPAGATION_ENABLED;

    /* Map with cached nested BeanWrappers */
    private Map nestedBeanWrappers;

    /** Map with custom PropertyEditor instances */
    private Map customEditors;

    //---------------------------------------------------------------------
    // Constructors
    //---------------------------------------------------------------------

    /**
     * Creates new BeanWrapperImpl with default event propagation (disabled)
     * @param object object wrapped by this BeanWrapper.
     * @throws BeansException if the object cannot be wrapped by a BeanWrapper
     */
    public BeanWrapperImpl(Object object) throws BeansException {
        this(object, DEFAULT_EVENT_PROPAGATION_ENABLED);
    }

    /**
     * Creates new BeanWrapperImpl, allowing specification of whether event
     * propagation is enabled.
     * @param object object wrapped by this BeanWrapper.
     * @param eventPropagationEnabled whether event propagation should be enabled
     * @throws BeansException if the object cannot be wrapped by a BeanWrapper
     */
    public BeanWrapperImpl(Object object, boolean eventPropagationEnabled) throws BeansException {
        this.eventPropagationEnabled = eventPropagationEnabled;
        setObject(object);
    }

    /**
     * Creates new BeanWrapperImpl, wrapping a new instance of the specified class
     * @param clazz class to instantiate and wrap
     * @throws BeansException if the class cannot be wrapped by a BeanWrapper
     */
    public BeanWrapperImpl(Class clazz) throws BeansException {
        this.cachedIntrospectionResults = CachedIntrospectionResults.forClass(clazz);
        setObject(BeanUtils.instantiateClass(clazz));
    }

    /**
     * Implementation method to switch the target object, replacing the cached introspection results
     * only if the class of the new object is different to that of the replaced object
     * @param object new target
     * @throws BeansException if the object cannot be changed
     */
    private void setObject(Object object) throws BeansException {
        if (object == null)
            throw new FatalBeanException("Cannot set BeanWrapperImpl target to a null object", null);
        this.object = object;
        if (cachedIntrospectionResults == null
                || !cachedIntrospectionResults.getBeanClass().equals(object.getClass())) {
            cachedIntrospectionResults = CachedIntrospectionResults.forClass(object.getClass());
        }
        setEventPropagationEnabled(this.eventPropagationEnabled);
        // assert: cachedIntrospectionResults != null
    }

    //---------------------------------------------------------------------
    // Implementation of BeanWrapper
    //---------------------------------------------------------------------

    public void setWrappedInstance(Object object) throws BeansException {
        setObject(object);
    }

    public void newWrappedInstance() throws BeansException {
        this.object = BeanUtils.instantiateClass(getWrappedClass());
        vetoableChangeSupport = new VetoableChangeSupport(object);
    }

    public Class getWrappedClass() {
        return object.getClass();
    }

    public Object getWrappedInstance() {
        return object;
    }

    public void registerCustomEditor(Class requiredType, String propertyPath, PropertyEditor propertyEditor) {
        if (propertyPath != null) {
            BeanWrapperImpl bw = getBeanWrapperForNestedProperty(propertyPath);
            bw.doRegisterCustomEditor(requiredType, getFinalPath(propertyPath), propertyEditor);
        } else {
            doRegisterCustomEditor(requiredType, propertyPath, propertyEditor);
        }
    }

    public void doRegisterCustomEditor(Class requiredType, String propertyName, PropertyEditor propertyEditor) {
        if (this.customEditors == null) {
            this.customEditors = new HashMap();
        }
        if (propertyName != null) {
            // consistency check
            PropertyDescriptor descriptor = getPropertyDescriptor(propertyName);
            if (requiredType != null && !descriptor.getPropertyType().isAssignableFrom(requiredType)) {
                throw new IllegalArgumentException("Types do not match: required=" + requiredType.getName()
                        + ", found=" + descriptor.getPropertyType());
            }
            this.customEditors.put(propertyName, propertyEditor);
        } else {
            if (requiredType == null) {
                throw new IllegalArgumentException("No propertyName and no requiredType specified");
            }
            this.customEditors.put(requiredType, propertyEditor);
        }
    }

    public PropertyEditor findCustomEditor(Class requiredType, String propertyPath) {
        if (propertyPath != null) {
            BeanWrapperImpl bw = getBeanWrapperForNestedProperty(propertyPath);
            return bw.doFindCustomEditor(requiredType, getFinalPath(propertyPath));
        } else {
            return doFindCustomEditor(requiredType, propertyPath);
        }
    }

    public PropertyEditor doFindCustomEditor(Class requiredType, String propertyName) {
        if (this.customEditors == null) {
            return null;
        }
        if (propertyName != null) {
            // check property-specific editor first
            PropertyDescriptor descriptor = getPropertyDescriptor(propertyName);
            PropertyEditor editor = (PropertyEditor) this.customEditors.get(propertyName);
            if (editor != null) {
                // consistency check
                if (requiredType != null) {
                    if (!descriptor.getPropertyType().isAssignableFrom(requiredType)) {
                        throw new IllegalArgumentException("Types do not match: required=" + requiredType.getName()
                                + ", found=" + descriptor.getPropertyType());
                    }
                }
                return editor;
            } else {
                if (requiredType == null) {
                    // try property type
                    requiredType = descriptor.getPropertyType();
                }
            }
        }
        // no property-specific editor -> check type-specific editor
        return (PropertyEditor) this.customEditors.get(requiredType);
    }

    /**
     * Convert the value to the required type (if necessary from a string),
     * to create a PropertyChangeEvent.
     * Conversions from String to any type use the setAsTest() method of
     * the PropertyEditor class. Note that a PropertyEditor must be registered
     * for this class for this to work. This is a standard Java Beans API.
     * A number of property editors are automatically registered by this class.
     * @param target target bean
     * @param propertyName name of the property
     * @param oldValue previous value, if available. May be null.
     * @param newValue proposed change value.
     * @param requiredType type we must convert to
     * @throws BeansException if there is an internal error
     * @return a PropertyChangeEvent, containing the converted type of the new
     * value.
     */
    private PropertyChangeEvent createPropertyChangeEventWithTypeConversionIfNecessary(Object target,
            String propertyName, Object oldValue, Object newValue, Class requiredType) throws BeansException {
        return new PropertyChangeEvent(target, propertyName, oldValue,
                doTypeConversionIfNecessary(target, propertyName, oldValue, newValue, requiredType));
    }

    /**
     * Convert the value to the required type (if necessary from a String).
     * Conversions from String to any type use the setAsText() method of
     * the PropertyEditor class. Note that a PropertyEditor must be registered
     * for this class for this to work. This is a standard Java Beans API.
     * A number of property editors are automatically registered by this class.
     * @param target target bean
     * @param propertyName name of the property
     * @param oldValue previous value, if available. May be null.
     * @param newValue proposed change value.
     * @param requiredType type we must convert to
     * @throws BeansException if there is an internal error
     * @return new value, possibly the result of type convertion.
     */
    public Object doTypeConversionIfNecessary(Object target, String propertyName, Object oldValue, Object newValue,
            Class requiredType) throws BeansException {
        // Only need to cast if value isn't null
        if (newValue != null) {
            // We may need to change the value of newValue
            // custom editor for this type?
            PropertyEditor pe = findCustomEditor(requiredType, propertyName);
            if ((pe != null || !requiredType.isAssignableFrom(newValue.getClass()))
                    && (newValue instanceof String)) {
                if (logger.isDebugEnabled())
                    logger.debug("Convert: String to " + requiredType);
                if (pe == null) {
                    // no custom editor -> check BeanWrapper's default editors
                    pe = (PropertyEditor) defaultEditors.get(requiredType);
                    if (pe == null) {
                        // no BeanWrapper default editor -> check standard editors
                        pe = PropertyEditorManager.findEditor(requiredType);
                    }
                }
                if (logger.isDebugEnabled())
                    logger.debug("Using property editor [" + pe + "]");
                if (pe != null) {
                    try {
                        pe.setAsText((String) newValue);
                        newValue = pe.getValue();
                    } catch (IllegalArgumentException ex) {
                        throw new TypeMismatchException(
                                new PropertyChangeEvent(target, propertyName, oldValue, newValue), requiredType,
                                ex);
                    }
                }
            }
        }
        return newValue;
    }

    public void setPropertyValue(String propertyName, Object value) throws PropertyVetoException, BeansException {
        setPropertyValue(new PropertyValue(propertyName, value));
    }

    /**
     * Is the property nested? That is, does it contain the nested
     * property separator (usually ".").
     * @param path property path
     * @return boolean is the property nested
     */
    private boolean isNestedProperty(String path) {
        return path.indexOf(NESTED_PROPERTY_SEPARATOR) != -1;
    }

    /**
     * Get the last component of the path. Also works if not nested.
     * @param nestedPath property path we know is nested
     * @return last component of the path (the property on the target bean)
     */
    private String getFinalPath(String nestedPath) {
        return nestedPath.substring(nestedPath.lastIndexOf(NESTED_PROPERTY_SEPARATOR) + 1);
    }

    /**
     * Recursively navigate to return a BeanWrapper for the nested path.
     * @param path property path, which may be nested
     * @return a BeanWrapper for the target bean
     */
    private BeanWrapperImpl getBeanWrapperForNestedProperty(String path) {
        int pos = path.indexOf(NESTED_PROPERTY_SEPARATOR);
        // Handle nested properties recursively
        if (pos > -1) {
            String nestedProperty = path.substring(0, pos);
            String nestedPath = path.substring(pos + 1);
            logger.debug(
                    "Navigating to property path '" + nestedPath + "' of nested property '" + nestedProperty + "'");
            BeanWrapperImpl nestedBw = getNestedBeanWrapper(nestedProperty);
            return nestedBw.getBeanWrapperForNestedProperty(nestedPath);
        } else {
            return this;
        }
    }

    /**
     * Retrieve a BeanWrapper for the given nested property.
     * Create a new one if not found in the cache.
     * <p>Note: Caching nested BeanWrappers is necessary now,
     * to keep registered custom editors for nested properties.
     * @param nestedProperty property to create the BeanWrapper for
     * @return the BeanWrapper instance, either cached or newly created
     */
    private BeanWrapperImpl getNestedBeanWrapper(String nestedProperty) {
        if (this.nestedBeanWrappers == null) {
            this.nestedBeanWrappers = new HashMap();
        }
        // get value of bean property
        Object propertyValue = getPropertyValue(nestedProperty);
        if (propertyValue == null) {
            throw new NullValueInNestedPathException(getWrappedClass(), nestedProperty);
        }
        // lookup cached sub-BeanWrapper, create new one if not found
        BeanWrapperImpl nestedBw = (BeanWrapperImpl) this.nestedBeanWrappers.get(propertyValue);
        if (nestedBw == null) {
            logger.debug("Creating new nested BeanWrapper for property '" + nestedProperty + "'");
            nestedBw = new BeanWrapperImpl(propertyValue, false);
            // inherit all type-specific PropertyEditors
            if (this.customEditors != null) {
                for (Iterator it = this.customEditors.keySet().iterator(); it.hasNext();) {
                    Object key = it.next();
                    if (key instanceof Class) {
                        Class requiredType = (Class) key;
                        PropertyEditor propertyEditor = (PropertyEditor) this.customEditors.get(key);
                        nestedBw.registerCustomEditor(requiredType, null, propertyEditor);
                    }
                }
            }
            this.nestedBeanWrappers.put(propertyValue, nestedBw);
        } else {
            logger.debug("Using cached nested BeanWrapper for property '" + nestedProperty + "'");
        }
        return nestedBw;
    }

    /**
     * Set an individual field.
     * All other setters go through this.
     * @param pv property value to use for update
     * @throws PropertyVetoException if a listeners throws a JavaBeans API veto
     * @throws BeansException if there's a low-level, fatal error
     */
    public void setPropertyValue(PropertyValue pv) throws PropertyVetoException, BeansException {

        if (isNestedProperty(pv.getName())) {
            try {
                BeanWrapper nestedBw = getBeanWrapperForNestedProperty(pv.getName());
                nestedBw.setPropertyValue(new PropertyValue(getFinalPath(pv.getName()), pv.getValue()));
                return;
            } catch (NullValueInNestedPathException ex) {
                // Let this through
                throw ex;
            } catch (FatalBeanException ex) {
                // Error in the nested path
                throw new NotWritablePropertyException(pv.getName(), getWrappedClass());
            }
        }

        if (!isWritableProperty(pv.getName())) {
            throw new NotWritablePropertyException(pv.getName(), getWrappedClass());
        }

        PropertyDescriptor pd = getPropertyDescriptor(pv.getName());
        Method writeMethod = pd.getWriteMethod();
        Method readMethod = pd.getReadMethod();
        Object oldValue = null; // May stay null if it's not a readable property
        PropertyChangeEvent propertyChangeEvent = null;

        try {
            if (readMethod != null && eventPropagationEnabled) {
                // Can only find existing value if it's a readable property
                try {
                    oldValue = readMethod.invoke(object, new Object[] {});
                } catch (Exception ex) {
                    // The getter threw an exception, so we couldn't retrieve the old value.
                    // We're not really interested in any exceptions at this point,
                    // so we merely log the problem and leave oldValue null
                    logger.warn("Failed to invoke getter '" + readMethod.getName()
                            + "' to get old property value before property change: getter probably threw an exception",
                            ex);
                }
            }

            // Old value may still be null
            propertyChangeEvent = createPropertyChangeEventWithTypeConversionIfNecessary(object, pv.getName(),
                    oldValue, pv.getValue(), pd.getPropertyType());

            // May throw PropertyVetoException: if this happens the PropertyChangeSupport
            // class fires a reversion event, and we jump out of this method, meaning
            // the change was never actually made
            if (eventPropagationEnabled) {
                vetoableChangeSupport.fireVetoableChange(propertyChangeEvent);
            }

            if (pd.getPropertyType().isPrimitive() && (pv.getValue() == null || "".equals(pv.getValue()))) {
                throw new IllegalArgumentException("Invalid value [" + pv.getValue() + "] for property ["
                        + pd.getName() + "] of primitive type [" + pd.getPropertyType() + "]");
            }

            // Make the change
            if (logger.isDebugEnabled())
                logger.debug("About to invoke write method [" + writeMethod + "] on object of class '"
                        + object.getClass().getName() + "'");
            writeMethod.invoke(object, new Object[] { propertyChangeEvent.getNewValue() });
            if (logger.isDebugEnabled())
                logger.debug("Invoked write method [" + writeMethod + "] ok");

            // If we get here we've changed the property OK and can broadcast it
            if (eventPropagationEnabled)
                propertyChangeSupport.firePropertyChange(propertyChangeEvent);
        } catch (InvocationTargetException ex) {
            if (ex.getTargetException() instanceof PropertyVetoException)
                throw (PropertyVetoException) ex.getTargetException();
            if (ex.getTargetException() instanceof ClassCastException)
                throw new TypeMismatchException(propertyChangeEvent, pd.getPropertyType(), ex.getTargetException());
            throw new MethodInvocationException(ex.getTargetException(), propertyChangeEvent);
        } catch (IllegalAccessException ex) {
            throw new FatalBeanException("illegal attempt to set property [" + pv + "] threw exception", ex);
        } catch (IllegalArgumentException ex) {
            throw new TypeMismatchException(propertyChangeEvent, pd.getPropertyType(), ex);
        }
    }

    /**
     * Bulk update from a Map.
     * Bulk updates from PropertyValues are more powerful: this method is
     * provided for convenience.
     * @param map map containing properties to set, as name-value pairs.
     * The map may include nested properties.
     * @throws BeansException if there's a fatal, low-level exception
     */
    public void setPropertyValues(Map map) throws BeansException {
        setPropertyValues(new MutablePropertyValues(map));
    }

    public void setPropertyValues(PropertyValues pvs) throws BeansException {
        setPropertyValues(pvs, false, null);
    }

    public void setPropertyValues(PropertyValues propertyValues, boolean ignoreUnknown,
            PropertyValuesValidator pvsValidator) throws BeansException {
        // Create only if needed
        PropertyVetoExceptionsException propertyVetoExceptionsException = new PropertyVetoExceptionsException(this);

        if (pvsValidator != null) {
            try {
                pvsValidator.validatePropertyValues(propertyValues);
            } catch (InvalidPropertyValuesException ipvex) {
                propertyVetoExceptionsException.addMissingFields(ipvex);
            }
        }

        PropertyValue[] pvs = propertyValues.getPropertyValues();
        for (int i = 0; i < pvs.length; i++) {
            try {
                // This method may throw ReflectionException, which won't be caught
                // here, if there is a critical failure such as no matching field.
                // We can attempt to deal only with less serious exceptions
                setPropertyValue(pvs[i]);
            }
            // Fatal ReflectionExceptions will just be rethrown
            catch (NotWritablePropertyException ex) {
                if (!ignoreUnknown)
                    throw ex;
                // Otherwise, just ignore it and continue...
            } catch (PropertyVetoException ex) {
                propertyVetoExceptionsException.addPropertyVetoException(ex);
            } catch (TypeMismatchException ex) {
                propertyVetoExceptionsException.addTypeMismatchException(ex);
            } catch (MethodInvocationException ex) {
                propertyVetoExceptionsException.addMethodInvocationException(ex);
            }
        } // for each property

        // If we encountered individual exceptions, throw the composite exception
        if (propertyVetoExceptionsException.getExceptionCount() > 0) {
            throw propertyVetoExceptionsException;
        }
    }

    public Object getPropertyValue(String propertyName) throws BeansException {
        if (isNestedProperty(propertyName)) {
            BeanWrapper nestedBw = getBeanWrapperForNestedProperty(propertyName);
            logger.debug("Final path in nested property value '" + propertyName + "' is '"
                    + getFinalPath(propertyName) + "'");
            return nestedBw.getPropertyValue(getFinalPath(propertyName));
        }

        PropertyDescriptor pd = getPropertyDescriptor(propertyName);
        Method readMethod = pd.getReadMethod();
        if (readMethod == null) {
            throw new FatalBeanException("Cannot get scalar property [" + propertyName + "]: not readable", null);
        }
        if (logger.isDebugEnabled())
            logger.debug("About to invoke read method [" + readMethod + "] on object of class '"
                    + object.getClass().getName() + "'");
        try {
            return readMethod.invoke(object, null);
        } catch (InvocationTargetException ex) {
            throw new FatalBeanException("Getter for property [" + propertyName + "] threw exception", ex);
        } catch (IllegalAccessException ex) {
            throw new FatalBeanException("Illegal attempt to get property [" + propertyName + "] threw exception",
                    ex);
        }
    }

    /**
     * Get the value of an indexed property.
     * @param propertyName name of the property to get value of
     * @param index index from 0 of the property
     * @return the value of the property
     * @throws BeansException if there's a fatal exception
     */
    public Object getIndexedPropertyValue(String propertyName, int index) throws BeansException {
        PropertyDescriptor pd = getPropertyDescriptor(propertyName);
        if (!(pd instanceof IndexedPropertyDescriptor))
            throw new FatalBeanException("Cannot get indexed property value for [" + propertyName
                    + "]: this property is not an indexed property", null);
        Method m = ((IndexedPropertyDescriptor) pd).getIndexedReadMethod();
        if (m == null)
            throw new FatalBeanException("Cannot get indexed property [" + propertyName + "]: not readable", null);
        try {
            return m.invoke(object, new Object[] { new Integer(index) });
        } catch (InvocationTargetException ex) {
            throw new FatalBeanException("getter for indexed property [" + propertyName + "] threw exception", ex);
        } catch (IllegalAccessException ex) {
            throw new FatalBeanException(
                    "illegal attempt to get indexed property [" + propertyName + "] threw exception", ex);
        }
    }

    /**
     * Method getProperties.
     * @return PropertyDescriptor[] property descriptor for the wrapped target
     * @throws BeansException if property descriptors cannot be obtained
     */
    public PropertyDescriptor[] getProperties() throws BeansException {
        return cachedIntrospectionResults.getBeanInfo().getPropertyDescriptors();
    }

    public PropertyDescriptor getPropertyDescriptor(String propertyName) throws BeansException {
        return cachedIntrospectionResults.getPropertyDescriptor(propertyName);
    }

    public boolean isReadableProperty(String propertyName) {
        try {
            return getPropertyDescriptor(propertyName).getReadMethod() != null;
        } catch (BeansException ex) {
            // Doesn't exist, so can't be readable
            return false;
        }
    }

    public boolean isWritableProperty(String propertyName) {
        try {
            return getPropertyDescriptor(propertyName).getWriteMethod() != null;
        } catch (BeansException ex) {
            // Doesn't exist, so can't be writable
            return false;
        }
    }

    public Object invoke(String methodName, Object[] args) throws BeansException {
        try {
            MethodDescriptor md = this.cachedIntrospectionResults.getMethodDescriptor(methodName);
            if (logger.isDebugEnabled())
                logger.debug("About to invoke method [" + methodName + "]");
            Object returnVal = md.getMethod().invoke(this.object, args);
            if (logger.isDebugEnabled())
                logger.debug("Successfully invoked method [" + methodName + "]");
            return returnVal;
        } catch (InvocationTargetException ex) {
            //if (ex.getTargetException() instanceof ClassCastException)
            //   throw new TypeMismatchException(propertyChangeEvent, pd.getPropertyType(), ex);
            throw new MethodInvocationException(ex.getTargetException(), methodName);
        } catch (IllegalAccessException ex) {
            throw new FatalBeanException("Illegal attempt to invoke method [" + methodName + "] threw exception",
                    ex);
        } catch (IllegalArgumentException ex) {
            throw new FatalBeanException("Illegal argument to method [" + methodName + "] threw exception", ex);
        }
    }

    public PropertyDescriptor[] getPropertyDescriptors() {
        return cachedIntrospectionResults.getBeanInfo().getPropertyDescriptors();
    }

    //---------------------------------------------------------------------
    // Bean event support
    //---------------------------------------------------------------------

    public void addVetoableChangeListener(VetoableChangeListener l) {
        if (eventPropagationEnabled)
            vetoableChangeSupport.addVetoableChangeListener(l);
    }

    public void removeVetoableChangeListener(VetoableChangeListener l) {
        if (eventPropagationEnabled)
            vetoableChangeSupport.removeVetoableChangeListener(l);
    }

    public void addVetoableChangeListener(String propertyName, VetoableChangeListener l) {
        if (eventPropagationEnabled)
            vetoableChangeSupport.addVetoableChangeListener(propertyName, l);
    }

    public void removeVetoableChangeListener(String propertyName, VetoableChangeListener l) {
        if (eventPropagationEnabled)
            vetoableChangeSupport.removeVetoableChangeListener(propertyName, l);
    }

    public void addPropertyChangeListener(PropertyChangeListener l) {
        if (eventPropagationEnabled)
            propertyChangeSupport.addPropertyChangeListener(l);
    }

    public void removePropertyChangeListener(PropertyChangeListener l) {
        if (eventPropagationEnabled)
            propertyChangeSupport.removePropertyChangeListener(l);
    }

    public void addPropertyChangeListener(String propertyName, PropertyChangeListener l) {
        if (eventPropagationEnabled)
            propertyChangeSupport.addPropertyChangeListener(propertyName, l);
    }

    public void removePropertyChangeListener(String propertyName, PropertyChangeListener l) {
        if (eventPropagationEnabled)
            propertyChangeSupport.removePropertyChangeListener(propertyName, l);
    }

    public boolean isEventPropagationEnabled() {
        return eventPropagationEnabled;
    }

    /**
     * Disabling event propagation improves performance.
     * @param flag whether event propagation should be enabled
     */
    public void setEventPropagationEnabled(boolean flag) {
        this.eventPropagationEnabled = flag;
        // Lazily initialize support for events if not already initialized
        if (eventPropagationEnabled && (vetoableChangeSupport == null || propertyChangeSupport == null)) {
            vetoableChangeSupport = new VetoableChangeSupport(object);
            propertyChangeSupport = new PropertyChangeSupport(object);
        }
    }

    //---------------------------------------------------------------------
    // Diagnostics
    //---------------------------------------------------------------------

    /**
     * This method is expensive! Only call for diagnostics and debugging reasons,
     * not in production
     * @return a string describing the state of this object
     */
    public String toString() {
        StringBuffer sb = new StringBuffer();
        try {
            sb.append("BeanWrapperImpl: eventPropagationEnabled=" + eventPropagationEnabled + " wrapping ["
                    + getWrappedInstance().getClass() + "]; ");
            PropertyDescriptor pds[] = getPropertyDescriptors();
            if (pds != null) {
                for (int i = 0; i < pds.length; i++) {
                    Object val = getPropertyValue(pds[i].getName());
                    String valStr = (val != null) ? val.toString() : "null";
                    sb.append(pds[i].getName() + "={" + valStr + "}");
                }
            }
        } catch (Exception ex) {
            sb.append("exception encountered: " + ex);
        }
        return sb.toString();
    }

}