1 /*
   2  * Copyright (c) 1997, 1999, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package javax.swing.text;
  26 
  27 import java.io.*;
  28 import javax.swing.Action;
  29 import javax.swing.JEditorPane;
  30 
  31 /**
  32  * Establishes the set of things needed by a text component
  33  * to be a reasonably functioning editor for some <em>type</em>
  34  * of text content.  The EditorKit acts as a factory for some
  35  * kind of policy.  For example, an implementation
  36  * of html and rtf can be provided that is replaceable
  37  * with other implementations.
  38  * <p>
  39  * A kit can safely store editing state as an instance
  40  * of the kit will be dedicated to a text component.
  41  * New kits will normally be created by cloning a
  42  * prototype kit.  The kit will have it's
  43  * <code>setComponent</code> method called to establish
  44  * it's relationship with a JTextComponent.
  45  *
  46  * @author  Timothy Prinzing
  47  */
  48 public abstract class EditorKit implements Cloneable, Serializable {
  49 
  50     /**
  51      * Construct an EditorKit.
  52      */
  53     public EditorKit() {
  54     }
  55 
  56     /**
  57      * Creates a copy of the editor kit.  This is implemented
  58      * to use <code>Object.clone()</code>.  If the kit cannot be cloned,
  59      * null is returned.
  60      *
  61      * @return the copy
  62      */
  63     public Object clone() {
  64         Object o;
  65         try {
  66             o = super.clone();
  67         } catch (CloneNotSupportedException cnse) {
  68             o = null;
  69         }
  70         return o;
  71     }
  72 
  73     /**
  74      * Called when the kit is being installed into the
  75      * a JEditorPane.
  76      *
  77      * @param c the JEditorPane
  78      */
  79     public void install(JEditorPane c) {
  80     }
  81 
  82     /**
  83      * Called when the kit is being removed from the
  84      * JEditorPane.  This is used to unregister any
  85      * listeners that were attached.
  86      *
  87      * @param c the JEditorPane
  88      */
  89     public void deinstall(JEditorPane c) {
  90     }
  91 
  92     /**
  93      * Gets the MIME type of the data that this
  94      * kit represents support for.
  95      *
  96      * @return the type
  97      */
  98     public abstract String getContentType();
  99 
 100     /**
 101      * Fetches a factory that is suitable for producing
 102      * views of any models that are produced by this
 103      * kit.
 104      *
 105      * @return the factory
 106      */
 107     public abstract ViewFactory getViewFactory();
 108 
 109     /**
 110      * Fetches the set of commands that can be used
 111      * on a text component that is using a model and
 112      * view produced by this kit.
 113      *
 114      * @return the set of actions
 115      */
 116     public abstract Action[] getActions();
 117 
 118     /**
 119      * Fetches a caret that can navigate through views
 120      * produced by the associated ViewFactory.
 121      *
 122      * @return the caret
 123      */
 124     public abstract Caret createCaret();
 125 
 126     /**
 127      * Creates an uninitialized text storage model
 128      * that is appropriate for this type of editor.
 129      *
 130      * @return the model
 131      */
 132     public abstract Document createDefaultDocument();
 133 
 134     /**
 135      * Inserts content from the given stream which is expected
 136      * to be in a format appropriate for this kind of content
 137      * handler.
 138      *
 139      * @param in  The stream to read from
 140      * @param doc The destination for the insertion.
 141      * @param pos The location in the document to place the
 142      *   content &gt;= 0.
 143      * @exception IOException on any I/O error
 144      * @exception BadLocationException if pos represents an invalid
 145      *   location within the document.
 146      */
 147     public abstract void read(InputStream in, Document doc, int pos)
 148         throws IOException, BadLocationException;
 149 
 150     /**
 151      * Writes content from a document to the given stream
 152      * in a format appropriate for this kind of content handler.
 153      *
 154      * @param out  The stream to write to
 155      * @param doc The source for the write.
 156      * @param pos The location in the document to fetch the
 157      *   content from &gt;= 0.
 158      * @param len The amount to write out &gt;= 0.
 159      * @exception IOException on any I/O error
 160      * @exception BadLocationException if pos represents an invalid
 161      *   location within the document.
 162      */
 163     public abstract void write(OutputStream out, Document doc, int pos, int len)
 164         throws IOException, BadLocationException;
 165 
 166     /**
 167      * Inserts content from the given stream which is expected
 168      * to be in a format appropriate for this kind of content
 169      * handler.
 170      * <p>
 171      * Since actual text editing is unicode based, this would
 172      * generally be the preferred way to read in the data.
 173      * Some types of content are stored in an 8-bit form however,
 174      * and will favor the InputStream.
 175      *
 176      * @param in  The stream to read from
 177      * @param doc The destination for the insertion.
 178      * @param pos The location in the document to place the
 179      *   content &gt;= 0.
 180      * @exception IOException on any I/O error
 181      * @exception BadLocationException if pos represents an invalid
 182      *   location within the document.
 183      */
 184     public abstract void read(Reader in, Document doc, int pos)
 185         throws IOException, BadLocationException;
 186 
 187     /**
 188      * Writes content from a document to the given stream
 189      * in a format appropriate for this kind of content handler.
 190      * <p>
 191      * Since actual text editing is unicode based, this would
 192      * generally be the preferred way to write the data.
 193      * Some types of content are stored in an 8-bit form however,
 194      * and will favor the OutputStream.
 195      *
 196      * @param out  The stream to write to
 197      * @param doc The source for the write.
 198      * @param pos The location in the document to fetch the
 199      *   content &gt;= 0.
 200      * @param len The amount to write out &gt;= 0.
 201      * @exception IOException on any I/O error
 202      * @exception BadLocationException if pos represents an invalid
 203      *   location within the document.
 204      */
 205     public abstract void write(Writer out, Document doc, int pos, int len)
 206         throws IOException, BadLocationException;
 207 
 208 }