propertyutilsbean.java

APACHE 公司出的java bean 工具包

                Object[] keyArray = new Object[1];
                keyArray[0] = key;
                result = invokeMethod(readMethod, bean, keyArray);
            } else {
                throw new NoSuchMethodException("Property '" + name +
                        "' has no mapped getter method on bean class '" +
                        bean.getClass() + "'");
            }
        } else {
          /* means that the result has to be retrieved from a map */
          Method readMethod = getReadMethod(descriptor);
          if (readMethod != null) {
            Object invokeResult = invokeMethod(readMethod, bean, new Object[0]);
            /* test and fetch from the map */
            if (invokeResult instanceof java.util.Map) {
              result = ((java.util.Map)invokeResult).get(key);
            }
          } else {
            throw new NoSuchMethodException("Property '" + name +
                    "' has no mapped getter method on bean class '" +
                    bean.getClass() + "'");
          }
        }
        return result;

    }


    /**
     * <p>Return the mapped property descriptors for this bean class.</p>
     *
     * <p><strong>FIXME</strong> - Does not work with DynaBeans.</p>
     *
     * @param beanClass Bean class to be introspected
     * @return the mapped property descriptors
     * @deprecated This method should not be exposed
     */
    public FastHashMap getMappedPropertyDescriptors(Class beanClass) {

        if (beanClass == null) {
            return null;
        }

        // Look up any cached descriptors for this bean class
        return (FastHashMap) mappedDescriptorsCache.get(beanClass);

    }


    /**
     * <p>Return the mapped property descriptors for this bean.</p>
     *
     * <p><strong>FIXME</strong> - Does not work with DynaBeans.</p>
     *
     * @param bean Bean to be introspected
     * @return the mapped property descriptors
     * @deprecated This method should not be exposed
     */
    public FastHashMap getMappedPropertyDescriptors(Object bean) {

        if (bean == null) {
            return null;
        }
        return (getMappedPropertyDescriptors(bean.getClass()));

    }


    /**
     * Return the value of the (possibly nested) property of the specified
     * name, for the specified bean, with no type conversions.
     *
     * @param bean Bean whose property is to be extracted
     * @param name Possibly nested name of the property to be extracted
     * @return the nested property value
     *
     * @exception IllegalAccessException if the caller does not have
     *  access to the property accessor method
     * @exception IllegalArgumentException if <code>bean</code> or
     *  <code>name</code> is null
     * @exception NestedNullException if a nested reference to a
     *  property returns null
     * @exception InvocationTargetException 
     * if the property accessor method throws an exception
     * @exception NoSuchMethodException if an accessor method for this
     *  propety cannot be found
     */
    public Object getNestedProperty(Object bean, String name)
            throws IllegalAccessException, InvocationTargetException,
            NoSuchMethodException {

        if (bean == null) {
            throw new IllegalArgumentException("No bean specified");
        }
        if (name == null) {
            throw new IllegalArgumentException("No name specified for bean class '" +
                    bean.getClass() + "'");
        }

        // Resolve nested references
        while (resolver.hasNested(name)) {
            String next = resolver.next(name);
            Object nestedBean = null;
            if (bean instanceof Map) {
                nestedBean = getPropertyOfMapBean((Map) bean, next);
            } else if (resolver.isMapped(next)) {
                nestedBean = getMappedProperty(bean, next);
            } else if (resolver.isIndexed(next)) {
                nestedBean = getIndexedProperty(bean, next);
            } else {
                nestedBean = getSimpleProperty(bean, next);
            }
            if (nestedBean == null) {
                throw new NestedNullException
                        ("Null property value for '" + name +
                        "' on bean class '" + bean.getClass() + "'");
            }
            bean = nestedBean;
            name = resolver.remove(name);
        }

        if (bean instanceof Map) {
            bean = getPropertyOfMapBean((Map) bean, name);
        } else if (resolver.isMapped(name)) {
            bean = getMappedProperty(bean, name);
        } else if (resolver.isIndexed(name)) {
            bean = getIndexedProperty(bean, name);
        } else {
            bean = getSimpleProperty(bean, name);
        }
        return bean;

    }

    /**
     * This method is called by getNestedProperty and setNestedProperty to
     * define what it means to get a property from an object which implements
     * Map. See setPropertyOfMapBean for more information.
     *
     * @param bean Map bean
     * @param propertyName The property name
     * @return the property value
     * 
     * @throws IllegalArgumentException when the propertyName is regarded as
     * being invalid.
     * 
     * @throws IllegalAccessException just in case subclasses override this
     * method to try to access real getter methods and find permission is denied.
     * 
     * @throws InvocationTargetException just in case subclasses override this
     * method to try to access real getter methods, and find it throws an
     * exception when invoked.
     * 
     * @throws NoSuchMethodException just in case subclasses override this
     * method to try to access real getter methods, and want to fail if
     * no simple method is available.
     */
    protected Object getPropertyOfMapBean(Map bean, String propertyName) 
        throws IllegalArgumentException, IllegalAccessException, 
        InvocationTargetException, NoSuchMethodException {

        if (resolver.isMapped(propertyName)) {
            String name = resolver.getProperty(propertyName);
            if (name == null || name.length() == 0) {
                propertyName = resolver.getKey(propertyName);
            }
        }

        if (resolver.isIndexed(propertyName) ||
            resolver.isMapped(propertyName)) {
            throw new IllegalArgumentException(
                    "Indexed or mapped properties are not supported on"
                    + " objects of type Map: " + propertyName);
        }

        return bean.get(propertyName);
    }



    /**
     * Return the value of the specified property of the specified bean,
     * no matter which property reference format is used, with no
     * type conversions.
     *
     * @param bean Bean whose property is to be extracted
     * @param name Possibly indexed and/or nested name of the property
     *  to be extracted
     * @return the property value
     *
     * @exception IllegalAccessException if the caller does not have
     *  access to the property accessor method
     * @exception IllegalArgumentException if <code>bean</code> or
     *  <code>name</code> is null
     * @exception InvocationTargetException if the property accessor method
     *  throws an exception
     * @exception NoSuchMethodException if an accessor method for this
     *  propety cannot be found
     */
    public Object getProperty(Object bean, String name)
            throws IllegalAccessException, InvocationTargetException,
            NoSuchMethodException {

        return (getNestedProperty(bean, name));

    }


    /**
     * <p>Retrieve the property descriptor for the specified property of the
     * specified bean, or return <code>null</code> if there is no such
     * descriptor.  This method resolves indexed and nested property
     * references in the same manner as other methods in this class, except
     * that if the last (or only) name element is indexed, the descriptor
     * for the last resolved property itself is returned.</p>
     *
     * <p><strong>FIXME</strong> - Does not work with DynaBeans.</p>
     *
     * @param bean Bean for which a property descriptor is requested
     * @param name Possibly indexed and/or nested name of the property for
     *  which a property descriptor is requested
     * @return the property descriptor
     *
     * @exception IllegalAccessException if the caller does not have
     *  access to the property accessor method
     * @exception IllegalArgumentException if <code>bean</code> or
     *  <code>name</code> is null
     * @exception IllegalArgumentException if a nested reference to a
     *  property returns null
     * @exception InvocationTargetException if the property accessor method
     *  throws an exception
     * @exception NoSuchMethodException if an accessor method for this
     *  propety cannot be found
     */
    public PropertyDescriptor getPropertyDescriptor(Object bean,
                                                           String name)
            throws IllegalAccessException, InvocationTargetException,
            NoSuchMethodException {

        if (bean == null) {
            throw new IllegalArgumentException("No bean specified");
        }
        if (name == null) {
            throw new IllegalArgumentException("No name specified for bean class '" +
                    bean.getClass() + "'");
        }

        // Resolve nested references
        while (resolver.hasNested(name)) {
            String next = resolver.next(name);
            Object nestedBean = null;
            if (bean instanceof Map) {
                nestedBean = getPropertyOfMapBean((Map)bean, next);
            } else if (resolver.isMapped(next)) {
                nestedBean = getMappedProperty(bean, next);
            } else if (resolver.isIndexed(next)) {
                nestedBean = getIndexedProperty(bean, next);
            } else {
                nestedBean = getSimpleProperty(bean, next);
            }
            if (nestedBean == null) {
                throw new NestedNullException
                        ("Null property value for '" + name +
                        "' on bean class '" + bean.getClass() + "'");
            }
            bean = nestedBean;
            name = resolver.remove(name);
        }

        // Remove any subscript from the final name value
        name = resolver.getProperty(name);

        // Look up and return this property from our cache
        // creating and adding it to the cache if not found.
        if ((bean == null) || (name == null)) {
            return (null);
        }
        
        PropertyDescriptor[] descriptors = getPropertyDescriptors(bean);
        if (descriptors != null) {
            
            for (int i = 0; i < descriptors.length; i++) {
                if (name.equals(descriptors[i].getName())) {
                    return (descriptors[i]);
                }
            }
        }

        PropertyDescriptor result = null;
        FastHashMap mappedDescriptors =
                getMappedPropertyDescriptors(bean);
        if (mappedDescriptors == null) {
            mappedDescriptors = new FastHashMap();
            mappedDescriptors.setFast(true);
            mappedDescriptorsCache.put(bean.getClass(), mappedDescriptors);
        }
        result = (PropertyDescriptor) mappedDescriptors.get(name);
        if (result == null) {
            // not found, try to create it
            try {
                result = new MappedPropertyDescriptor(name, bean.getClass());
            } catch (IntrospectionException ie) {
                /* Swallow IntrospectionException
                 * TODO: Why?
                 */
            }
            if (result != null) {
                mappedDescriptors.put(name, result);
            }
        }
        
        return result;

    }