defaultelement.java

解决如何把XML应用到JAVA里问题

        if (contentShadow instanceof List) {
            List list = (List) contentShadow;

            return list.iterator();
        } else {
            if (contentShadow != null) {
                return createSingleIterator(contentShadow);
            } else {
                return EMPTY_ITERATOR;
            }
        }
    }

    public List attributes() {
        return new ContentListFacade(this, attributeList());
    }

    public void setAttributes(List attributes) {
        if (attributes instanceof ContentListFacade) {
            attributes = ((ContentListFacade) attributes).getBackingList();
        }

        this.attributes = attributes;
    }

    public Iterator attributeIterator() {
        final Object attributesShadow = this.attributes;

        if (attributesShadow instanceof List) {
            List list = (List) attributesShadow;

            return list.iterator();
        } else if (attributesShadow != null) {
            return createSingleIterator(attributesShadow);
        } else {
            return EMPTY_ITERATOR;
        }
    }

    public Attribute attribute(int index) {
        final Object attributesShadow = this.attributes;

        if (attributesShadow instanceof List) {
            List list = (List) attributesShadow;

            return (Attribute) list.get(index);
        } else if ((attributesShadow != null) && (index == 0)) {
            return (Attribute) attributesShadow;
        } else {
            return null;
        }
    }

    public int attributeCount() {
        final Object attributesShadow = this.attributes;

        if (attributesShadow instanceof List) {
            List list = (List) attributesShadow;

            return list.size();
        } else {
            return (attributesShadow != null) ? 1 : 0;
        }
    }

    public Attribute attribute(String name) {
        final Object attributesShadow = this.attributes;

        if (attributesShadow instanceof List) {
            List list = (List) attributesShadow;

            int size = list.size();

            for (int i = 0; i < size; i++) {
                Attribute attribute = (Attribute) list.get(i);

                if (name.equals(attribute.getName())) {
                    return attribute;
                }
            }
        } else if (attributesShadow != null) {
            Attribute attribute = (Attribute) attributesShadow;

            if (name.equals(attribute.getName())) {
                return attribute;
            }
        }

        return null;
    }

    public Attribute attribute(QName qName) {
        final Object attributesShadow = this.attributes;

        if (attributesShadow instanceof List) {
            List list = (List) attributesShadow;

            int size = list.size();

            for (int i = 0; i < size; i++) {
                Attribute attribute = (Attribute) list.get(i);

                if (qName.equals(attribute.getQName())) {
                    return attribute;
                }
            }
        } else if (attributesShadow != null) {
            Attribute attribute = (Attribute) attributesShadow;

            if (qName.equals(attribute.getQName())) {
                return attribute;
            }
        }

        return null;
    }

    public Attribute attribute(String name, Namespace namespace) {
        return attribute(getDocumentFactory().createQName(name, namespace));
    }

    public void add(Attribute attribute) {
        if (attribute.getParent() != null) {
            String message = "The Attribute already has an existing parent \""
                    + attribute.getParent().getQualifiedName() + "\"";

            throw new IllegalAddException(this, attribute, message);
        }

        if (attribute.getValue() == null) {
            // try remove a previous attribute with the same
            // name since adding an attribute with a null value
            // is equivalent to removing it.
            Attribute oldAttribute = attribute(attribute.getQName());

            if (oldAttribute != null) {
                remove(oldAttribute);
            }
        } else {
            if (attributes == null) {
                attributes = attribute;
            } else {
                attributeList().add(attribute);
            }

            childAdded(attribute);
        }
    }

    public boolean remove(Attribute attribute) {
        boolean answer = false;
        final Object attributesShadow = this.attributes;

        if (attributesShadow instanceof List) {
            List list = (List) attributesShadow;

            answer = list.remove(attribute);

            if (!answer) {
                // we may have a copy of the attribute
                Attribute copy = attribute(attribute.getQName());

                if (copy != null) {
                    list.remove(copy);

                    answer = true;
                }
            }
        } else if (attributesShadow != null) {
            if (attribute.equals(attributesShadow)) {
                this.attributes = null;

                answer = true;
            } else {
                // we may have a copy of the attribute
                Attribute other = (Attribute) attributesShadow;

                if (attribute.getQName().equals(other.getQName())) {
                    attributes = null;

                    answer = true;
                }
            }
        }

        if (answer) {
            childRemoved(attribute);
        }

        return answer;
    }

    // Implementation methods
    // -------------------------------------------------------------------------
    protected void addNewNode(Node node) {
        final Object contentShadow = content;

        if (contentShadow == null) {
            this.content = node;
        } else {
            if (contentShadow instanceof List) {
                List list = (List) contentShadow;

                list.add(node);
            } else {
                List list = createContentList();

                list.add(contentShadow);

                list.add(node);

                this.content = list;
            }
        }

        childAdded(node);
    }

    protected boolean removeNode(Node node) {
        boolean answer = false;
        final Object contentShadow = content;

        if (contentShadow != null) {
            if (contentShadow == node) {
                this.content = null;

                answer = true;
            } else if (contentShadow instanceof List) {
                List list = (List) contentShadow;

                answer = list.remove(node);
            }
        }

        if (answer) {
            childRemoved(node);
        }

        return answer;
    }

    protected List contentList() {
        final Object contentShadow = content;

        if (contentShadow instanceof List) {
            return (List) contentShadow;
        } else {
            List list = createContentList();

            if (contentShadow != null) {
                list.add(contentShadow);
            }

            this.content = list;

            return list;
        }
    }

    protected List attributeList() {
        final Object attributesShadow = this.attributes;

        if (attributesShadow instanceof List) {
            return (List) attributesShadow;
        } else if (attributesShadow != null) {
            List list = createAttributeList();

            list.add(attributesShadow);

            this.attributes = list;

            return list;
        } else {
            List list = createAttributeList();

            this.attributes = list;

            return list;
        }
    }

    protected List attributeList(int size) {
        final Object attributesShadow = this.attributes;

        if (attributesShadow instanceof List) {
            return (List) attributesShadow;
        } else if (attributesShadow != null) {
            List list = createAttributeList(size);

            list.add(attributesShadow);

            this.attributes = list;

            return list;
        } else {
            List list = createAttributeList(size);

            this.attributes = list;

            return list;
        }
    }

    protected void setAttributeList(List attributeList) {
        this.attributes = attributeList;
    }

    protected DocumentFactory getDocumentFactory() {
        DocumentFactory factory = qname.getDocumentFactory();

        return (factory != null) ? factory : DOCUMENT_FACTORY;
    }
}

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