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Diffstat (limited to 'libjava/classpath/javax/swing/text/html/parser/DTD.java')
| -rw-r--r-- | libjava/classpath/javax/swing/text/html/parser/DTD.java | 609 |
1 files changed, 609 insertions, 0 deletions
diff --git a/libjava/classpath/javax/swing/text/html/parser/DTD.java b/libjava/classpath/javax/swing/text/html/parser/DTD.java new file mode 100644 index 000000000..09b50fee7 --- /dev/null +++ b/libjava/classpath/javax/swing/text/html/parser/DTD.java @@ -0,0 +1,609 @@ +/* DTD.java -- + Copyright (C) 2005 Free Software Foundation, Inc. + +This file is part of GNU Classpath. + +GNU Classpath is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2, or (at your option) +any later version. + +GNU Classpath is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GNU Classpath; see the file COPYING. If not, write to the +Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 USA. + +Linking this library statically or dynamically with other modules is +making a combined work based on this library. Thus, the terms and +conditions of the GNU General Public License cover the whole +combination. + +As a special exception, the copyright holders of this library give you +permission to link this library with independent modules to produce an +executable, regardless of the license terms of these independent +modules, and to copy and distribute the resulting executable under +terms of your choice, provided that you also meet, for each linked +independent module, the terms and conditions of the license of that +module. An independent module is a module which is not derived from +or based on this library. If you modify this library, you may extend +this exception to your version of the library, but you are not +obligated to do so. If you do not wish to do so, delete this +exception statement from your version. */ + + +package javax.swing.text.html.parser; + +import java.io.DataInputStream; +import java.io.EOFException; +import java.io.IOException; +import java.io.ObjectInputStream; +import java.lang.reflect.Field; +import java.lang.reflect.Modifier; +import java.util.BitSet; +import java.util.Hashtable; +import java.util.StringTokenizer; +import java.util.Vector; + +/** + * <p>Representation or the SGML DTD document. + * Provides basis for describing a syntax of the + * HTML documents. The fields of this class are NOT initialized in + * constructor. You need to do this separately before passing this data + * structure to the HTML parser. The subclasses with the fields, pre- + * initialized, for example, for HTML 4.01, can be available only between + * the implementation specific classes + * ( for example, {@link gnu.javax.swing.text.html.parser.HTML_401F } + * in this implementation).</p> + * <p> + * If you need more information about SGML DTD documents, + * the author suggests to read SGML tutorial on + * <a href="http://www.w3.org/TR/WD-html40-970708/intro/sgmltut.html" + * >http://www.w3.org/TR/WD-html40-970708/intro/sgmltut.html</a>. + * We also recommend Goldfarb C.F (1991) <i>The SGML Handbook</i>, + * Oxford University Press, 688 p, ISBN: 0198537379. + * </p> + * <p> + * Warning: the html, head and other tag fields will only be automatically + * assigned if the VM has the correctly implemented reflection mechanism. + * As these fields are not used anywhere in the implementation, not + * exception will be thrown in the opposite case. + * </p> + * + * @author Audrius Meskauskas, Lithuania (AudriusA@Bioinformatics.org) + */ +public class DTD + implements DTDConstants +{ + /** + * The version of the persistent data format. + * @specnote This was made <code>final</code> in 1.5. + */ + public static final int FILE_VERSION = 1; + + /** + * The table of existing available DTDs. + */ + static Hashtable<String,DTD> dtdHash = new Hashtable<String,DTD>(); + + /** + * The applet element for this DTD. + */ + public Element applet; + + /** + * The base element for this DTD. + */ + public Element base; + + /** + * The body element for this DTD. + */ + public Element body; + + /** + * The head element for this DTD. + */ + public Element head; + + /** + * The html element for this DTD. + */ + public Element html; + + /** + * The isindex element of for this DTD. + */ + public Element isindex; + + /** + * The meta element for this DTD. + */ + public Element meta; + + /** + * The p element for this DTD. + */ + public Element p; + + /** + * The param element for this DTD. + */ + public Element param; + + /** + * The pcdata for this DTD. + */ + public Element pcdata; + + /** + * The title element for this DTD. + */ + public Element title; + + /** + * The element for accessing all DTD elements by name. + */ + public Hashtable<String,Element> elementHash = + new Hashtable<String,Element>(); + + /** + * The entity table for accessing all DTD entities by name. + */ + public Hashtable<Object, Entity> entityHash = new Hashtable<Object, Entity>(); + + /** + * The name of this DTD. + */ + public String name; + + /** + * Contains all elements in this DTD. The + * javax.swing.text.html.parser.Element#index field of all elements + * in this vector is set to the element position in this vector. + */ + public Vector<Element> elements = new Vector<Element>(); + + /** Create a new DTD with the specified name. */ + protected DTD(String a_name) + { + name = a_name; + } + + /** Get this DTD by name. The current implementation + * only looks in the internal table of DTD documents. If no corresponding + * entry is found, the new entry is created, placed into + * the table and returned. */ + public static DTD getDTD(String name) + throws IOException + { + DTD d = dtdHash.get(name); + + if (d == null) + { + d = new DTD(name); + dtdHash.put(d.name, d); + } + + return d; + } + + /** + * Get the element by the element name. If the element is not yet + * defined, it is newly created and placed into the element table. + * If the element name matches (ingoring case) a public non static + * element field in this class, this field is assigned to the value + * of the newly created element. + */ + public Element getElement(String element_name) + { + return newElement(element_name); + } + + /** + * Get the element by the value of its + * {@link javax.swing.text.html.parser.Element#index} field. + */ + public Element getElement(int index) + { + return elements.get(index); + } + + /** + * Get the entity with the given identifier. + * @param id that can be returned by + * {@link javax.swing.text.html.parser.Entity#name2type(String an_entity)} + * @return The entity from this DTD or null if there is no entity with + * such id or such entity is not present in the table of this instance. + */ + public Entity getEntity(int id) + { + String name = Entity.mapper.get(id); + + if (name != null) + return entityHash.get(name); + else + return null; + } + + /** + * Get the named entity by its name. + */ + public Entity getEntity(String entity_name) + { + return entityHash.get(entity_name); + } + + /** + * Get the name of this instance of DTD + */ + public String getName() + { + return name; + } + + /** + * Creates, adds into the entity table and returns the + * character entity like <code>&lt;</code> + * (means '<code><</code>' ); + * @param name The entity name (without heading & and closing ;) + * @param type The entity type + * @param character The entity value (single character) + * @return The created entity + */ + public Entity defEntity(String name, int type, int character) + { + Entity e = newEntity(name, type); + e.data = new char[] { (char) character }; + return e; + } + + /** + * Define the attributes for the element with the given name. + * If the element is not exist, it is created. + * @param forElement + * @param attributes + */ + public void defineAttributes(String forElement, AttributeList attributes) + { + Element e = elementHash.get(forElement.toLowerCase()); + + if (e == null) + e = newElement(forElement); + + e.atts = attributes; + } + + /** + * Defines the element and adds it to the element table. Sets the + * <code>Element.index</code> field to the value, unique for this + * instance of DTD. If the element with the given name already exists, + * replaces all other its settings by the method argument values. + * @param name the name of the element + * @param type the type of the element + * @param headless true if the element needs no starting tag + * (should not occur in HTML). + * @param tailless true if the element needs no ending tag (like + * <code><hr></code> + * @param content the element content + * @param exclusions the set of elements that must not occur inside + * this element. The <code>Element.index</code> value defines which + * bit in this bitset corresponds to that element. + * @param inclusions the set of elements that can occur inside this + * element. the <code>Element.index</code> value defines which + * bit in this bitset corresponds to that element. + * @param attributes the element attributes. + * @return the newly defined element. + */ + public Element defineElement(String name, int type, boolean headless, + boolean tailless, ContentModel content, + BitSet exclusions, BitSet inclusions, + AttributeList attributes + ) + { + Element e = newElement(name); + e.type = type; + e.oStart = headless; + e.oEnd = tailless; + e.content = content; + e.exclusions = exclusions; + e.inclusions = inclusions; + e.atts = attributes; + + return e; + } + + /** + * Creates, intializes and adds to the entity table the new + * entity. + * @param name the name of the entity + * @param type the type of the entity + * @param data the data section of the entity + * @return the created entity + */ + public Entity defineEntity(String name, int type, char[] data) + { + Entity e = newEntity(name, type); + e.data = data; + + return e; + } + + /** Place this DTD into the DTD table. */ + public static void putDTDHash(String name, DTD dtd) + { + dtdHash.put(name, dtd); + } + + /** + * <p>Reads DTD from an archived format. This format is not standardized + * and differs between implementations.</p><p> This implementation + * reads and defines all entities and elements using + * ObjectInputStream. The elements and entities can be written into the + * stream in any order. The objects other than elements and entities + * are ignored.</p> + * @param stream A data stream to read from. + * @throws java.io.IOException If one is thrown by the input stream + */ + public void read(DataInputStream stream) + throws java.io.IOException + { + ObjectInputStream oi = new ObjectInputStream(stream); + Object def; + try + { + while (true) + { + def = oi.readObject(); + if (def instanceof Element) + { + Element e = (Element) def; + elementHash.put(e.name.toLowerCase(), e); + assignField(e); + } + else if (def instanceof Entity) + { + Entity e = (Entity) def; + entityHash.put(e.name, e); + } + } + } + catch (ClassNotFoundException ex) + { + throw new IOException(ex.getMessage()); + } + catch (EOFException ex) + { + // ok EOF + } + } + + /** + * Returns the name of this instance of DTD. + */ + public String toString() + { + return name; + } + + /** + * Creates and returns new attribute (not an attribute list). + * @param name the name of this attribute + * @param type the type of this attribute (FIXED, IMPLIED or + * REQUIRED from <code>DTDConstants</code>). + * @param modifier the modifier of this attribute + * @param default_value the default value of this attribute + * @param allowed_values the allowed values of this attribute. The multiple + * possible values in this parameter are supposed to be separated by + * '|', same as in SGML DTD <code><!ATTLIST </code>tag. This parameter + * can be null if no list of allowed values is specified. + * @param atts the previous attribute of this element. This is + * placed to the field + * {@link javax.swing.text.html.parser.AttributeList#next }, + * creating a linked list. + * @return The attributes. + */ + protected AttributeList defAttributeList(String name, int type, int modifier, + String default_value, + String allowed_values, + AttributeList atts + ) + { + AttributeList al = new AttributeList(name); + al.modifier = modifier; + al.value = default_value; + al.next = atts; + + if (allowed_values != null) + { + StringTokenizer st = new StringTokenizer(allowed_values, " \t|"); + Vector<String> v = new Vector<String>(st.countTokens()); + + while (st.hasMoreTokens()) + v.add(st.nextToken()); + + al.values = v; + } + + return al; + } + + /** + * Creates a new content model. + * @param type specifies the BNF operation for this content model. + * The valid operations are documented in the + * {@link javax.swing.text.html.parser.ContentModel#type }. + * @param content the content of this content model + * @param next if the content model is specified by BNF-like + * expression, contains the rest of this expression. + * @return The newly created content model. + */ + protected ContentModel defContentModel(int type, Object content, + ContentModel next + ) + { + ContentModel model = new ContentModel(); + model.type = type; + model.next = next; + model.content = content; + + return model; + } + + /** + * Defines a new element and adds it to the element table. + * If the element alredy exists, + * overrides it settings with the specified values. + * @param name the name of the new element + * @param type the type of the element + * @param headless true if the element needs no starting tag + * @param tailless true if the element needs no closing tag + * @param content the element content. + * @param exclusions the elements that must be excluded from the + * content of this element, in all levels of the hierarchy. + * @param inclusions the elements that can be included as the + * content of this element. + * @param attributes the element attributes. + * @return the created or updated element. + */ + protected Element defElement(String name, int type, boolean headless, + boolean tailless, ContentModel content, + String[] exclusions, String[] inclusions, + AttributeList attributes + ) + { + // compute the bit sets + BitSet exclude = bitSet(exclusions); + BitSet include = bitSet(inclusions); + + Element e = + defineElement(name, type, headless, tailless, content, exclude, include, + attributes + ); + + return e; + } + + /** + * Creates, intializes and adds to the entity table the new + * entity. + * @param name the name of the entity + * @param type the type of the entity + * @param data the data section of the entity + * @return the created entity + */ + protected Entity defEntity(String name, int type, String data) + { + Entity e = newEntity(name, type); + e.data = data.toCharArray(); + + return e; + } + + private void assignField(Element e) + { + String element_name = e.name; + try + { + // Assign the field via reflection. + Field f = getClass().getField(element_name.toLowerCase()); + if ((f.getModifiers() & Modifier.PUBLIC) != 0) + if ((f.getModifiers() & Modifier.STATIC) == 0) + if (f.getType().isAssignableFrom(e.getClass())) + f.set(this, e); + } + catch (IllegalAccessException ex) + { + unexpected(ex); + } + catch (NoSuchFieldException ex) + { + // This is ok. + } + + // Some virtual machines may still lack the proper + // implementation of reflection. As the tag fields + // are not used anywhere in this implementation, + // (and this class is also rarely used by the end user), + // it may be better not to crash everything by throwing an error + // for each case when the HTML parsing is required. + catch (Throwable t) + { + // This VM has no reflection mechanism implemented! + if (t instanceof OutOfMemoryError) + throw (Error) t; + } + } + + /** + * Create the bit set for this array of elements. + * The unknown elements are automatically defined and added + * to the element table. + * @param elements + * @return The bit set. + */ + private BitSet bitSet(String[] elements) + { + BitSet b = new BitSet(); + + for (int i = 0; i < elements.length; i++) + { + Element e = getElement(elements [ i ]); + + if (e == null) + e = newElement(elements [ i ]); + + b.set(e.index); + } + + return b; + } + + /** + * Find the element with the given name in the element table. + * If not find, create a new element with this name and add to the + * table. + * @param name the name of the element + * @return the found or created element. + */ + private Element newElement(String name) + { + Element e = elementHash.get(name.toLowerCase()); + + if (e == null) + { + e = new Element(); + e.name = name; + e.index = elements.size(); + elements.add(e); + elementHash.put(e.name.toLowerCase(), e); + assignField(e); + } + return e; + } + + /** + * Creates and adds to the element table the entity with an + * unitialized data section. Used internally. + * @param name the name of the entity + * @param type the type of the entity, a bitwise combination + * of GENERAL, PARAMETER, SYSTEM and PUBLIC. + * + * @return the created entity + */ + private Entity newEntity(String name, int type) + { + Entity e = new Entity(name, type, null); + entityHash.put(e.name, e); + return e; + } + + private void unexpected(Exception ex) + { + throw new Error("This should never happen, report a bug", ex); + } +} |