propertyutilsbean.java

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    }


    /**
     * <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
     * @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 getPropertyType(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");
        }

        // Special handling for DynaBeans
        if (bean instanceof DynaBean) {
            DynaProperty descriptor =
                    ((DynaBean) bean).getDynaClass().getDynaProperty(name);
            if (descriptor == null) {
                return (null);
            }
            Class type = descriptor.getType();
            if (type == null) {
                return (null);
            } else if (type.isArray()) {
                return (type.getComponentType());
            } else {
                return (type);
            }
        }

        PropertyDescriptor descriptor =
                getPropertyDescriptor(bean, name);
        if (descriptor == null) {
            return (null);
        } else if (descriptor instanceof IndexedPropertyDescriptor) {
            return (((IndexedPropertyDescriptor) descriptor).
                    getIndexedPropertyType());
        } else if (descriptor instanceof MappedPropertyDescriptor) {
            return (((MappedPropertyDescriptor) descriptor).
                    getMappedPropertyType());
        } else {
            return (descriptor.getPropertyType());
        }

    }


    /**
     * <p>Return an accessible property getter method for this property,
     * if there is one; otherwise return <code>null</code>.</p>
     *
     * <p><strong>FIXME</strong> - Does not work with DynaBeans.</p>
     *
     * @param descriptor Property descriptor to return a getter for
     */
    public Method getReadMethod(PropertyDescriptor descriptor) {

        return (MethodUtils.getAccessibleMethod(descriptor.getReadMethod()));

    }


    /**
     * Return the value of the specified simple property of the specified
     * bean, with no type conversions.
     *
     * @param bean Bean whose property is to be extracted
     * @param name 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 IllegalArgumentException if the property name
     *  is nested or indexed
     * @exception InvocationTargetException if the property accessor method
     *  throws an exception
     * @exception NoSuchMethodException if an accessor method for this
     *  propety cannot be found
     */
    public Object getSimpleProperty(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");
        }

        // Validate the syntax of the property name
        if (name.indexOf(PropertyUtils.NESTED_DELIM) >= 0) {
            throw new IllegalArgumentException
                    ("Nested property names are not allowed");
        } else if (name.indexOf(PropertyUtils.INDEXED_DELIM) >= 0) {
            throw new IllegalArgumentException
                    ("Indexed property names are not allowed");
        } else if (name.indexOf(PropertyUtils.MAPPED_DELIM) >= 0) {
            throw new IllegalArgumentException
                    ("Mapped property names are not allowed");
        }

        // Handle DynaBean instances specially
        if (bean instanceof DynaBean) {
            DynaProperty descriptor =
                    ((DynaBean) bean).getDynaClass().getDynaProperty(name);
            if (descriptor == null) {
                throw new NoSuchMethodException("Unknown property '" +
                        name + "'");
            }
            return (((DynaBean) bean).get(name));
        }

        // Retrieve the property getter method for the specified property
        PropertyDescriptor descriptor =
                getPropertyDescriptor(bean, name);
        if (descriptor == null) {
            throw new NoSuchMethodException("Unknown property '" +
                    name + "'");
        }
        Method readMethod = getReadMethod(descriptor);
        if (readMethod == null) {
            throw new NoSuchMethodException("Property '" + name +
                    "' has no getter method");
        }

        // Call the property getter and return the value
        Object value = invokeMethod(readMethod, bean, new Object[0]);
        return (value);

    }


    /**
     * <p>Return an accessible property setter method for this property,
     * if there is one; otherwise return <code>null</code>.</p>
     *
     * <p><strong>FIXME</strong> - Does not work with DynaBeans.</p>
     *
     * @param descriptor Property descriptor to return a setter for
     */
    public Method getWriteMethod(PropertyDescriptor descriptor) {

        return (MethodUtils.getAccessibleMethod(descriptor.getWriteMethod()));

    }


    /**
     * <p>Return <code>true</code> if the specified property name identifies
     * a readable property on the specified bean; otherwise, return
     * <code>false</code>.
     *
     * @param bean Bean to be examined (may be a {@link DynaBean}
     * @param name Property name to be evaluated
     *
     * @exception IllegalArgumentException if <code>bean</code>
     *  or <code>name</code> is <code>null</code>
     *
     * @since BeanUtils 1.6
     */
    public boolean isReadable(Object bean, String name) {

        // Validate method parameters
        if (bean == null) {
            throw new IllegalArgumentException("No bean specified");
        }
        if (name == null) {
            throw new IllegalArgumentException("No name specified");
        }

        // Return the requested result
        if (bean instanceof DynaBean) {
            // All DynaBean properties are readable
            return (((DynaBean) bean).getDynaClass().getDynaProperty(name) != null);
        } else {
            try {
                PropertyDescriptor desc =
                    getPropertyDescriptor(bean, name);
                if (desc != null) {
                    Method readMethod = desc.getReadMethod();
                    if ((readMethod == null) &&
                        (desc instanceof IndexedPropertyDescriptor)) {
                        readMethod = ((IndexedPropertyDescriptor) desc).getIndexedReadMethod();
                    }
                    return (readMethod != null);
                } else {
                    return (false);
                }
            } catch (IllegalAccessException e) {
                return (false);
            } catch (InvocationTargetException e) {
                return (false);
            } catch (NoSuchMethodException e) {
                return (false);
            }
        }

    }


    /**
     * <p>Return <code>true</code> if the specified property name identifies
     * a writeable property on the specified bean; otherwise, return
     * <code>false</code>.
     *
     * @param bean Bean to be examined (may be a {@link DynaBean}
     * @param name Property name to be evaluated
     *
     * @exception IllegalPointerException if <code>bean</code>
     *  or <code>name</code> is <code>null</code>
     *
     * @since BeanUtils 1.6
     */
    public boolean isWriteable(Object bean, String name) {

        // Validate method parameters
        if (bean == null) {
            throw new IllegalArgumentException("No bean specified");
        }
        if (name == null) {
            throw new IllegalArgumentException("No name specified");
        }

        // Return the requested result
        if (bean instanceof DynaBean) {
            // All DynaBean properties are writeable
            return (((DynaBean) bean).getDynaClass().getDynaProperty(name) != null);