lazydynabean.java

apache beanutils开源项目源码

     *
     * @exception IllegalArgumentException if this is not an existing property
     *  name for our DynaClass and the MutableDynaClass is restricted
     * @exception ConversionException if the specified value cannot be
     *  converted to the type required for this property
     * @exception NullPointerException if an attempt is made to set a
     *  primitive property to null
     */
    public void set(String name, Object value) {

        // If the property doesn't exist, then add it
        if (!isDynaProperty(name)) {

            if (dynaClass.isRestricted()) {
                throw new IllegalArgumentException
                    ("Invalid property name '" + name + "' (DynaClass is restricted)");
            }
            if (value == null) {
                dynaClass.add(name);
            } else {
                dynaClass.add(name, value.getClass());
            }

        }

        DynaProperty descriptor = dynaClass.getDynaProperty(name);

        if (value == null) {
            if (descriptor.getType().isPrimitive()) {
                throw new NullPointerException
                        ("Primitive value for '" + name + "'");
            }
        } else if (!isAssignable(descriptor.getType(), value.getClass())) {
            throw new ConversionException
                    ("Cannot assign value of type '" +
                    value.getClass().getName() +
                    "' to property '" + name + "' of type '" +
                    descriptor.getType().getName() + "'");
        }

        // Set the property's value
        values.put(name, value);

    }

    /**
     * Set the value of an indexed property with the specified name.
     *
     * @param name Name of the property whose value is to be set
     * @param index Index of the property to be set
     * @param value Value to which this property is to be set
     *
     * @exception ConversionException if the specified value cannot be
     *  converted to the type required for this property
     * @exception IllegalArgumentException if there is no property
     *  of the specified name
     * @exception IllegalArgumentException if the specified property
     *  exists, but is not indexed
     * @exception IndexOutOfBoundsException if the specified index
     *  is outside the range of the underlying property
     */
    public void set(String name, int index, Object value) {

        // If its not a property, then create default indexed property
        if (!isDynaProperty(name)) {
            set(name, defaultIndexedProperty(name));
        }

        // Get the indexed property
        Object indexedProperty = get(name);

        // Check that the property is indexed
        if (!dynaClass.getDynaProperty(name).isIndexed()) {
            throw new IllegalArgumentException
                ("Non-indexed property for '" + name + "[" + index + "]'"
                            + dynaClass.getDynaProperty(name).getType().getName());
        }

        // Grow indexed property to appropriate size
        indexedProperty = growIndexedProperty(name, indexedProperty, index);

        // Set the value in an array
        if (indexedProperty.getClass().isArray()) {
            Array.set(indexedProperty, index, value);
        } else if (indexedProperty instanceof List) {
            ((List)indexedProperty).set(index, value);
        } else {
            throw new IllegalArgumentException
                ("Non-indexed property for '" + name + "[" + index + "]' "
                            + indexedProperty.getClass().getName());
        }

    }

    /**
     * Set the value of a mapped property with the specified name.
     *
     * @param name Name of the property whose value is to be set
     * @param key Key of the property to be set
     * @param value Value to which this property is to be set
     *
     * @exception ConversionException if the specified value cannot be
     *  converted to the type required for this property
     * @exception IllegalArgumentException if there is no property
     *  of the specified name
     * @exception IllegalArgumentException if the specified property
     *  exists, but is not mapped
     */
    public void set(String name, String key, Object value) {

        // If the 'mapped' property doesn't exist, then add it
        if (!isDynaProperty(name)) {
            set(name, defaultMappedProperty(name));
        }

        // Get the mapped property
        Object mappedProperty = get(name);

        // Check that the property is mapped
        if (!dynaClass.getDynaProperty(name).isMapped()) {
            throw new IllegalArgumentException
                ("Non-mapped property for '" + name + "(" + key + ")'"
                            + dynaClass.getDynaProperty(name).getType().getName());
        }

        // Set the value in the Map
        ((Map)mappedProperty).put(key, value);

    }

    // ------------------- protected Methods ----------------------------------

    protected Object growIndexedProperty(String name, Object indexedProperty, int index) {

        // Grow a List to the appropriate size
        if (indexedProperty instanceof List) {

            List list = (List)indexedProperty;
            while (index >= list.size()) {
                list.add(null);
            }

        }

        // Grow an Array to the appropriate size
        if ((indexedProperty.getClass().isArray())) {

            int length = Array.getLength(indexedProperty);
            if (index >= length) {
                Class componentType = indexedProperty.getClass().getComponentType();
                Object newArray = Array.newInstance(componentType, (index + 1));
                System.arraycopy(indexedProperty, 0, newArray, 0, length);
                indexedProperty = newArray;
                set(name, indexedProperty);
                int newLength = Array.getLength(indexedProperty);
                for (int i = length; i < newLength; i++) {
                    Array.set(indexedProperty, i, createProperty(name+"["+i+"]", componentType));
                }
            }
        }

        return indexedProperty;

    }

    /**
     * Create a new Instance of a Property
     */
    protected Object createProperty(String name, Class type) {

        // Create Lists, arrays or DynaBeans
        if (type.isArray() || List.class.isAssignableFrom(type)) {
            return createIndexedProperty(name, type);
        }

        if (Map.class.isAssignableFrom(type)) {
            return createMappedProperty(name, type);
        }

        if (DynaBean.class.isAssignableFrom(type)) {
            return createDynaBeanProperty(name, type);
        }

        if (type.isPrimitive()) {
            return createPrimitiveProperty(name, type);
        }

        if (Number.class.isAssignableFrom(type)) {
            return createNumberProperty(name, type);
        }

        return createOtherProperty(name, type);

    }

    /**
     * Create a new Instance of an 'Indexed' Property
     */
    protected Object createIndexedProperty(String name, Class type) {

        // Create the indexed object
        Object indexedProperty = null;

        if (type == null) {

            indexedProperty = defaultIndexedProperty(name);

        } else if (type.isArray()) {

            indexedProperty = Array.newInstance(type.getComponentType(), 0);

        } else if (List.class.isAssignableFrom(type)) {
            if (type.isInterface()) {
                indexedProperty = defaultIndexedProperty(name);
            } else {
                try {
                    indexedProperty = type.newInstance();
                }
                catch (Exception ex) {
                    throw new IllegalArgumentException
                        ("Error instantiating indexed property of type '" +
                                   type.getName() + "' for '" + name + "' " + ex);
                }
            }
        } else {

            throw new IllegalArgumentException
                    ("Non-indexed property of type '" + type.getName() + "' for '" + name + "'");
        }

        return indexedProperty;

    }

    /**
     * Create a new Instance of a 'Mapped' Property
     */
    protected Object createMappedProperty(String name, Class type) {

        // Create the mapped object
        Object mappedProperty = null;

        if (type == null) {

            mappedProperty = defaultMappedProperty(name);

        } else if (type.isInterface()) {

            mappedProperty = defaultMappedProperty(name);

        } else if (Map.class.isAssignableFrom(type)) {
            try {
                mappedProperty = type.newInstance();
            }
            catch (Exception ex) {
                throw new IllegalArgumentException
                    ("Error instantiating mapped property of type '" + type.getName() + "' for '" + name + "' " + ex);
            }
        } else {

            throw new IllegalArgumentException
                    ("Non-mapped property of type '" + type.getName() + "' for '" + name + "'");
        }

        return mappedProperty;

    }

    /**
     * Create a new Instance of a 'Mapped' Property
     */
    protected Object createDynaBeanProperty(String name, Class type) {
        try {
            return type.newInstance();
        }
        catch (Exception ex) {
            if (logger.isWarnEnabled()) {
                logger.warn("Error instantiating DynaBean property of type '" + type.getName() + "' for '" + name + "' " + ex);
            }
            return null;
        }
    }

    /**
     * Create a new Instance of a 'Primitive' Property
     */
    protected Object createPrimitiveProperty(String name, Class type) {

        if (type == Boolean.TYPE) {
            return Boolean.FALSE;
        } else if (type == Integer.TYPE) {
            return Integer_ZERO;
        } else if (type == Long.TYPE) {
            return Long_ZERO;
        } else if (type == Double.TYPE) {
            return Double_ZERO;
        } else if (type == Float.TYPE) {
            return Float_ZERO;
        } else if (type == Byte.TYPE) {
            return Byte_ZERO;
        } else if (type == Short.TYPE) {
            return Short_ZERO;
        } else if (type == Character.TYPE) {
            return Character_SPACE;
        } else {
            return null;
        }

    }

    /**
     * Create a new Instance of a 'Primitive' Property
     */
    protected Object createNumberProperty(String name, Class type) {

        return null;

    }

    /**
     * Create a new Instance of a 'Mapped' Property
     */
    protected Object createOtherProperty(String name, Class type) {

        if (type == String.class || type == Boolean.class ||
            type == Character.class || Date.class.isAssignableFrom(type)) {
            return null;
        }

        try {
            return type.newInstance();
        }
        catch (Exception ex) {
            if (logger.isWarnEnabled()) {
                logger.warn("Error instantiating property of type '" + type.getName() + "' for '" + name + "' " + ex);
            }
            return null;
        }
    }

    /**
     * <p>Creates a new <code>ArrayList</code> for an 'indexed' property
     *    which doesn't exist.</p>
     *
     * <p>This method shouls be overriden if an alternative <code>List</code>
     *    or <code>Array</code> implementation is required for 'indexed' properties.</p>
     *
     * @param name Name of the 'indexed property.
     */
    protected Object defaultIndexedProperty(String name) {
        return new ArrayList();
    }

    /**
     * <p>Creates a new <code>HashMap</code> for a 'mapped' property
     *    which doesn't exist.</p>
     *
     * <p>This method can be overriden if an alternative <code>Map</code>
     *    implementation is required for 'mapped' properties.</p>
     *
     * @param name Name of the 'mapped property.
     */
    protected Map defaultMappedProperty(String name) {
        return new HashMap();
    }

    /**
     * Indicates if there is a property with the specified name.
     */
    protected boolean isDynaProperty(String name) {

        if (name == null) {
            throw new IllegalArgumentException("No property name specified");
        }

        // Handle LazyDynaClasses
        if (dynaClass instanceof LazyDynaClass) {
            return ((LazyDynaClass)dynaClass).isDynaProperty(name);
        }

        // Handle other MutableDynaClass
        return dynaClass.getDynaProperty(name) == null ? false : true;

    }

    /**
     * Is an object of the source class assignable to the destination class?
     *
     * @param dest Destination class
     * @param source Source class
     */
    protected boolean isAssignable(Class dest, Class source) {

        if (dest.isAssignableFrom(source) ||
                ((dest == Boolean.TYPE) && (source == Boolean.class)) ||
                ((dest == Byte.TYPE) && (source == Byte.class)) ||
                ((dest == Character.TYPE) && (source == Character.class)) ||
                ((dest == Double.TYPE) && (source == Double.class)) ||
                ((dest == Float.TYPE) && (source == Float.class)) ||
                ((dest == Integer.TYPE) && (source == Integer.class)) ||
                ((dest == Long.TYPE) && (source == Long.class)) ||
                ((dest == Short.TYPE) && (source == Short.class))) {
            return (true);
        } else {
            return (false);
        }

    }

    /**
     * <p>Creates a new instance of the <code>Map</code>.</p>
     */
    protected Map newMap() {
        return new HashMap();
    }

}