propertyutilsbean.java

apache beanutils开源项目源码

            } else {
                bean = getSimpleProperty(bean, next);
            }
            if (bean == null) {
                throw new NestedNullException
                        ("Null property value for '" +
                        name.substring(0, indexOfNESTED_DELIM) + "'");
            }
            name = name.substring(indexOfNESTED_DELIM + 1);
        }

        indexOfINDEXED_DELIM = name.indexOf(PropertyUtils.INDEXED_DELIM);
        indexOfMAPPED_DELIM = name.indexOf(PropertyUtils.MAPPED_DELIM);

        if (bean instanceof Map) {
            bean = ((Map) bean).get(name);
        } else if (indexOfMAPPED_DELIM >= 0) {
            bean = getMappedProperty(bean, name);
        } else if (indexOfINDEXED_DELIM >= 0) {
            bean = getIndexedProperty(bean, name);
        } else {
            bean = getSimpleProperty(bean, name);
        }
        return bean;

    }


    /**
     * 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
     *
     * @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
     *
     * @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");
        }

        // Resolve nested references
        while (true) {            
            int period = findNextNestedIndex(name);
            if (period < 0) {
                break;
            }
            String next = name.substring(0, period);
            int indexOfINDEXED_DELIM = next.indexOf(PropertyUtils.INDEXED_DELIM);
            int indexOfMAPPED_DELIM = next.indexOf(PropertyUtils.MAPPED_DELIM);
            if (indexOfMAPPED_DELIM >= 0 &&
                    (indexOfINDEXED_DELIM < 0 ||
                    indexOfMAPPED_DELIM < indexOfINDEXED_DELIM)) {
                bean = getMappedProperty(bean, next);
            } else {
                if (indexOfINDEXED_DELIM >= 0) {
                    bean = getIndexedProperty(bean, next);
                } else {
                    bean = getSimpleProperty(bean, next);
                }
            }
            if (bean == null) {
                throw new IllegalArgumentException
                        ("Null property value for '" +
                        name.substring(0, period) + "'");
            }
            name = name.substring(period + 1);
        }

        // Remove any subscript from the final name value
        int left = name.indexOf(PropertyUtils.INDEXED_DELIM);
        if (left >= 0) {
            name = name.substring(0, left);
        }
        left = name.indexOf(PropertyUtils.MAPPED_DELIM);
        if (left >= 0) {
            name = name.substring(0, left);
        }

        // 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) {
            }
            if (result != null) {
                mappedDescriptors.put(name, result);
            }
        }
        
        return result;

    }
    
    private int findNextNestedIndex(String expression)
    {
        // walk back from the end to the start 
        // and find the first index that 
        int bracketCount = 0;
        for (int i=0, size=expression.length(); i<size ; i++) {
            char at = expression.charAt(i);
            switch (at) {
                case PropertyUtils.NESTED_DELIM:
                    if (bracketCount < 1) {
                        return i;
                    }
                    break;
                    
                case PropertyUtils.MAPPED_DELIM:
                case PropertyUtils.INDEXED_DELIM:
                    // not bothered which
                    ++bracketCount;
                    break;
                
                case PropertyUtils.MAPPED_DELIM2:
                case PropertyUtils.INDEXED_DELIM2:
                    // not bothered which
                    --bracketCount;
                    break;            
            }
        }
        // can't find any
        return -1;
    }


    /**
     * <p>Retrieve the property descriptors for the specified class,
     * introspecting and caching them the first time a particular bean class
     * is encountered.</p>
     *
     * <p><strong>FIXME</strong> - Does not work with DynaBeans.</p>
     *
     * @param beanClass Bean class for which property descriptors are requested
     *
     * @exception IllegalArgumentException if <code>beanClass</code> is null
     */
    public PropertyDescriptor[]
            getPropertyDescriptors(Class beanClass) {

        if (beanClass == null) {
            throw new IllegalArgumentException("No bean class specified");
        }

        // Look up any cached descriptors for this bean class
        PropertyDescriptor descriptors[] = null;
        descriptors =
                (PropertyDescriptor[]) descriptorsCache.get(beanClass);
        if (descriptors != null) {
            return (descriptors);
        }

        // Introspect the bean and cache the generated descriptors
        BeanInfo beanInfo = null;
        try {
            beanInfo = Introspector.getBeanInfo(beanClass);
        } catch (IntrospectionException e) {
            return (new PropertyDescriptor[0]);
        }
        descriptors = beanInfo.getPropertyDescriptors();
        if (descriptors == null) {
            descriptors = new PropertyDescriptor[0];
        }
        descriptorsCache.put(beanClass, descriptors);
        return (descriptors);

    }


    /**
     * <p>Retrieve the property descriptors for the specified bean,
     * introspecting and caching them the first time a particular bean class
     * is encountered.</p>
     *
     * <p><strong>FIXME</strong> - Does not work with DynaBeans.</p>
     *
     * @param bean Bean for which property descriptors are requested
     *
     * @exception IllegalArgumentException if <code>bean</code> is null
     */
    public PropertyDescriptor[] getPropertyDescriptors(Object bean) {

        if (bean == null) {
            throw new IllegalArgumentException("No bean specified");
        }
        return (getPropertyDescriptors(bean.getClass()));

    }


    /**
     * <p>Return the Java Class repesenting the property editor class that has
     * been registered for this property (if any).  This method follows the
     * same name resolution rules used by <code>getPropertyDescriptor()</code>,
     * so if the last element of a name reference is indexed, the property
     * editor for the underlying property's class is returned.</p>
     *
     * <p>Note that <code>null</code> will be returned if there is no property,
     * or if there is no registered property editor class.  Because this
     * return value is ambiguous, you should determine the existence of the
     * property itself by other means.</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
     *
     * @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 Class getPropertyEditorClass(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");
        }

        PropertyDescriptor descriptor =
                getPropertyDescriptor(bean, name);
        if (descriptor != null) {
            return (descriptor.getPropertyEditorClass());
        } else {
            return (null);
        }

    }


    /**
     * Return the Java Class representing the property type of the specified
     * property, or <code>null</code> if there is no such property for the
     * specified bean.  This method follows the same name resolution rules
     * used by <code>getPropertyDescriptor()</code>, so if the last element
     * of a name reference is indexed, the type of the property itself will
     * be returned.  If the last (or only) element has no property with the
     * specified name, <code>null</code> is returned.
     *
     * @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
     *
     * @exception IllegalAccessException if the caller does not have
     *  access to the property accessor method