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Diffstat (limited to 'libjava/gnu/xml/pipeline/PipelineFactory.java')
| -rw-r--r-- | libjava/gnu/xml/pipeline/PipelineFactory.java | 723 |
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diff --git a/libjava/gnu/xml/pipeline/PipelineFactory.java b/libjava/gnu/xml/pipeline/PipelineFactory.java deleted file mode 100644 index f88ab164311..00000000000 --- a/libjava/gnu/xml/pipeline/PipelineFactory.java +++ /dev/null @@ -1,723 +0,0 @@ -/* PipelineFactory.java -- - Copyright (C) 1999,2000,2001 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 gnu.xml.pipeline; - -import java.io.File; -import java.io.FileOutputStream; -import java.io.IOException; -import java.io.OutputStream; -import java.io.OutputStreamWriter; -import java.lang.reflect.Constructor; -import java.util.StringTokenizer; - -import org.xml.sax.*; -import org.xml.sax.ext.*; - - -/** - * This provides static factory methods for creating simple event pipelines. - * These pipelines are specified by strings, suitable for passing on - * command lines or embedding in element attributes. For example, one way - * to write a pipeline that restores namespace syntax, validates (stopping - * the pipeline on validity errors) and then writes valid data to standard - * output is this: <pre> - * nsfix | validate | write ( stdout )</pre> - * - * <p> In this syntax, the tokens are always separated by whitespace, and each - * stage of the pipeline may optionally have a parameter (which can be a - * pipeline) in parentheses. Interior stages are called filters, and the - * rightmost end of a pipeline is called a terminus. - * - * <p> Stages are usually implemented by a single class, which may not be - * able to act as both a filter and a terminus; but any terminus can be - * automatically turned into a filter, through use of a {@link TeeConsumer}. - * The stage identifiers are either class names, or are one of the following - * short identifiers built into this class. (Most of these identifiers are - * no more than aliases for classes.) The built-in identifiers include:</p> - - <table border="1" cellpadding="3" cellspacing="0"> - <tr bgcolor="#ccccff" class="TableHeadingColor"> - <th align="center" width="5%">Stage</th> - <th align="center" width="9%">Parameter</th> - <th align="center" width="1%">Terminus</th> - <th align="center">Description</th> - </tr> - - <tr valign="top" align="center"> - <td><a href="../dom/Consumer.html">dom</a></td> - <td><em>none</em></td> - <td> yes </td> - <td align="left"> Applications code can access a DOM Document built - from the input event stream. When used as a filter, this buffers - data up to an <em>endDocument</em> call, and then uses a DOM parser - to report everything that has been recorded (which can easily be - less than what was reported to it). </td> - </tr> - <tr valign="top" align="center"> - <td><a href="NSFilter.html">nsfix</a></td> - <td><em>none</em></td> - <td>no</td> - <td align="left">This stage ensures that the XML element and attribute - names in its output use namespace prefixes and declarations correctly. - That is, so that they match the "Namespace plus LocalName" naming data - with which each XML element and attribute is already associated. </td> - </tr> - <tr valign="top" align="center"> - <td><a href="EventFilter.html">null</a></td> - <td><em>none</em></td> - <td>yes</td> - <td align="left">This stage ignores all input event data.</td> - </tr> - <tr valign="top" align="center"> - <td><a href="CallFilter.html">server</a></td> - <td><em>required</em><br> server URL </td> - <td>no</td> - <td align="left">Sends its input as XML request to a remote server, - normally a web application server using the HTTP or HTTPS protocols. - The output of this stage is the parsed response from that server.</td> - </tr> - <tr valign="top" align="center"> - <td><a href="TeeConsumer.html">tee</a></td> - <td><em>required</em><br> first pipeline</td> - <td>no</td> - <td align="left">This sends its events down two paths; its parameter - is a pipeline descriptor for the first path, and the second path - is the output of this stage.</td> - </tr> - - <tr valign="top" align="center"> - <td><a href="ValidationConsumer.html">validate</a></td> - <td><em>none</em></td> - <td>yes</td> - <td align="left">This checks for validity errors, and reports them - through its error handler. The input must include declaration events - and some lexical events. </td> - </tr> - <tr valign="top" align="center"> - <td><a href="WellFormednessFilter.html">wf</a></td> - <td><em>none</em></td> - <td>yes</td> - <td align="left"> This class provides some basic "well formedness" - tests on the input event stream, and reports a fatal error if any - of them fail. One example: start/end calls for elements must match. - No SAX parser is permitted to produce malformed output, but other - components can easily do so.</td> - </tr> - <tr valign="top" align="center"> - <td>write</td> - <td><em>required</em><br> "stdout", "stderr", or filename</td> - <td>yes</td> - <td align="left"> Writes its input to the specified output, as pretty - printed XML text encoded using UTF-8. Input events must be well - formed and "namespace fixed", else the output won't be XML (or possibly - namespace) conformant. The symbolic names represent - <em>System.out</em> and <em>System.err</em> respectively; names must - correspond to files which don't yet exist.</td> - </tr> - <tr valign="top" align="center"> - <td>xhtml</td> - <td><em>required</em><br> "stdout", "stderr", or filename</td> - <td>yes</td> - <td align="left"> Like <em>write</em> (above), except that XHTML rules - are followed. The XHTML 1.0 Transitional document type is declared, - and only ASCII characters are written (for interoperability). Other - characters are written as entity or character references; the text is - pretty printed.</td> - </tr> - <tr valign="top" align="center"> - <td><a href="XIncludeFilter.html">xinclude</a></td> - <td><em>none</em></td> - <td>no</td> - <td align="left">This stage handles XInclude processing. - This is like entity inclusion, except that the included content - is declared in-line rather than in the DTD at the beginning of - a document. - </td> - </tr> - <tr valign="top" align="center"> - <td><a href="XsltFilter.html">xslt</a></td> - <td><em>required</em><br> XSLT stylesheet URI</td> - <td>no</td> - <td align="left">This stage handles XSLT transformation - according to a stylesheet. - The implementation of the transformation may not actually - stream data, although if such an XSLT engine is in use - then that can happen. - </td> - </tr> - - </table> - - * <p> Note that {@link EventFilter#bind} can automatically eliminate - * some filters by setting SAX2 parser features appropriately. This means - * that you can routinely put filters like "nsfix", "validate", or "wf" at the - * front of a pipeline (for components that need inputs conditioned to match - * that level of correctness), and know that it won't actually be used unless - * it's absolutely necessary. - * - * @author David Brownell - */ -public class PipelineFactory -{ - /** - * Creates a simple pipeline according to the description string passed in. - */ - public static EventConsumer createPipeline (String description) - throws IOException - { - return createPipeline (description, null); - } - - /** - * Extends an existing pipeline by prepending the filter pipeline to the - * specified consumer. Some pipelines need more customization than can - * be done through this simplified syntax. When they are set up with - * direct API calls, use this method to merge more complex pipeline - * segments with easily configured ones. - */ - public static EventConsumer createPipeline ( - String description, - EventConsumer next - ) throws IOException - { - // tokens are (for now) what's separated by whitespace; - // very easy to parse, but IDs never have spaces. - - StringTokenizer tokenizer; - String tokens []; - - tokenizer = new StringTokenizer (description); - tokens = new String [tokenizer.countTokens ()]; - for (int i = 0; i < tokens.length; i++) - tokens [i] = tokenizer.nextToken (); - - PipelineFactory factory = new PipelineFactory (); - Pipeline pipeline = factory.parsePipeline (tokens, next); - - return pipeline.createPipeline (); - } - - - private PipelineFactory () { /* NYET */ } - - - /** - * Extends an existing pipeline by prepending a pre-tokenized filter - * pipeline to the specified consumer. Tokens are class names (or the - * predefined aliases) left and right parenthesis, and the vertical bar. - */ - public static EventConsumer createPipeline ( - String tokens [], - EventConsumer next - ) throws IOException - { - PipelineFactory factory = new PipelineFactory (); - Pipeline pipeline = factory.parsePipeline (tokens, next); - - return pipeline.createPipeline (); - } - - - private String tokens []; - private int index; - - private Pipeline parsePipeline (String toks [], EventConsumer next) - { - tokens = toks; - index = 0; - - Pipeline retval = parsePipeline (next); - - if (index != toks.length) - throw new ArrayIndexOutOfBoundsException ( - "extra token: " + tokens [index]); - return retval; - } - - // pipeline ::= stage | stage '|' pipeline - private Pipeline parsePipeline (EventConsumer next) - { - Pipeline retval = new Pipeline (parseStage ()); - - // minimal pipelines: "stage" and "... | id" - if (index > (tokens.length - 2) - || !"|".equals (tokens [index]) - ) { - retval.next = next; - return retval; - } - index++; - retval.rest = parsePipeline (next); - return retval; - } - - // stage ::= id | id '(' pipeline ')' - private Stage parseStage () - { - Stage retval = new Stage (tokens [index++]); - - // minimal stages: "id" and "id ( id )" - if (index > (tokens.length - 2) - || !"(".equals (tokens [index]) /*)*/ - ) - return retval; - - index++; - retval.param = parsePipeline (null); - if (index >= tokens.length) - throw new ArrayIndexOutOfBoundsException ( - "missing right paren"); - if (/*(*/ !")".equals (tokens [index++])) - throw new ArrayIndexOutOfBoundsException ( - "required right paren, not: " + tokens [index - 1]); - return retval; - } - - - // - // these classes obey the conventions for constructors, so they're - // only built in to this table of shortnames - // - // - filter (one or two types of arglist) - // * last constructor is 'next' element - // * optional (first) string parameter - // - // - terminus (one or types of arglist) - // * optional (only) string parameter - // - // terminus stages are transformed into filters if needed, by - // creating a "tee". filter stages aren't turned to terminus - // stages though; either eliminate such stages, or add some - // terminus explicitly. - // - private static final String builtinStages [][] = { - { "dom", "gnu.xml.dom.Consumer" }, - { "nsfix", "gnu.xml.pipeline.NSFilter" }, - { "null", "gnu.xml.pipeline.EventFilter" }, - { "server", "gnu.xml.pipeline.CallFilter" }, - { "tee", "gnu.xml.pipeline.TeeConsumer" }, - { "validate", "gnu.xml.pipeline.ValidationConsumer" }, - { "wf", "gnu.xml.pipeline.WellFormednessFilter" }, - { "xinclude", "gnu.xml.pipeline.XIncludeFilter" }, - { "xslt", "gnu.xml.pipeline.XsltFilter" }, - -// XXX want: option for validate, to preload external part of a DTD - - // xhtml, write ... nyet generic-ready - }; - - private static class Stage - { - String id; - Pipeline param; - - Stage (String name) - { id = name; } - - public String toString () - { - if (param == null) - return id; - return id + " ( " + param + " )"; - } - - private void fail (String message) - throws IOException - { - throw new IOException ("in '" + id - + "' stage of pipeline, " + message); - } - - EventConsumer createStage (EventConsumer next) - throws IOException - { - String name = id; - - // most builtins are just class aliases - for (int i = 0; i < builtinStages.length; i++) { - if (id.equals (builtinStages [i][0])) { - name = builtinStages [i][1]; - break; - } - } - - // Save output as XML or XHTML text - if ("write".equals (name) || "xhtml".equals (name)) { - String filename; - boolean isXhtml = "xhtml".equals (name); - OutputStream out = null; - TextConsumer consumer; - - if (param == null) - fail ("parameter is required"); - - filename = param.toString (); - if ("stdout".equals (filename)) - out = System.out; - else if ("stderr".equals (filename)) - out = System.err; - else { - File f = new File (filename); - -/* - if (!f.isAbsolute ()) - fail ("require absolute file paths"); - */ - if (f.exists ()) - fail ("file already exists: " + f.getName ()); - -// XXX this races against the existence test - out = new FileOutputStream (f); - } - - if (!isXhtml) - consumer = new TextConsumer (out); - else - consumer = new TextConsumer ( - new OutputStreamWriter (out, "8859_1"), - true); - - consumer.setPrettyPrinting (true); - if (next == null) - return consumer; - return new TeeConsumer (consumer, next); - - } else { - // - // Here go all the builtins that are just aliases for - // classes, and all stage IDs that started out as such - // class names. The following logic relies on several - // documented conventions for constructor invocation. - // - String msg = null; - - try { - Class klass = Class.forName (name); - Class argTypes [] = null; - Constructor constructor = null; - boolean filter = false; - Object params [] = null; - Object obj = null; - - // do we need a filter stage? - if (next != null) { - // "next" consumer is always passed, with - // or without the optional string param - if (param == null) { - argTypes = new Class [1]; - argTypes [0] = EventConsumer.class; - - params = new Object [1]; - params [0] = next; - - msg = "no-param filter"; - } else { - argTypes = new Class [2]; - argTypes [0] = String.class; - argTypes [1] = EventConsumer.class; - - params = new Object [2]; - params [0] = param.toString (); - params [1] = next; - - msg = "one-param filter"; - } - - - try { - constructor = klass.getConstructor (argTypes); - } catch (NoSuchMethodException e) { - // try creating a filter from a - // terminus and a tee - filter = true; - msg += " built from "; - } - } - - // build from a terminus stage, with or - // without the optional string param - if (constructor == null) { - String tmp; - - if (param == null) { - argTypes = new Class [0]; - params = new Object [0]; - - tmp = "no-param terminus"; - } else { - argTypes = new Class [1]; - argTypes [0] = String.class; - - params = new Object [1]; - params [0] = param.toString (); - - tmp = "one-param terminus"; - } - if (msg == null) - msg = tmp; - else - msg += tmp; - constructor = klass.getConstructor (argTypes); - // NOT creating terminus by dead-ending - // filters ... users should think about - // that one, something's likely wrong - } - - obj = constructor.newInstance (params); - - // return EventConsumers directly, perhaps after - // turning them into a filter - if (obj instanceof EventConsumer) { - if (filter) - return new TeeConsumer ((EventConsumer) obj, next); - return (EventConsumer) obj; - } - - // if it's not a handler, it's an error - // we can wrap handlers in a filter - EventFilter retval = new EventFilter (); - boolean updated = false; - - if (obj instanceof ContentHandler) { - retval.setContentHandler ((ContentHandler) obj); - updated = true; - } - if (obj instanceof DTDHandler) { - retval.setDTDHandler ((DTDHandler) obj); - updated = true; - } - if (obj instanceof LexicalHandler) { - retval.setProperty ( - EventFilter.PROPERTY_URI + "lexical-handler", - obj); - updated = true; - } - if (obj instanceof DeclHandler) { - retval.setProperty ( - EventFilter.PROPERTY_URI + "declaration-handler", - obj); - updated = true; - } - - if (!updated) - fail ("class is neither Consumer nor Handler"); - - if (filter) - return new TeeConsumer (retval, next); - return retval; - - } catch (IOException e) { - throw e; - - } catch (NoSuchMethodException e) { - fail (name + " constructor missing -- " + msg); - - } catch (ClassNotFoundException e) { - fail (name + " class not found"); - - } catch (Exception e) { - // e.printStackTrace (); - fail ("stage not available: " + e.getMessage ()); - } - } - // NOTREACHED - return null; - } - } - - private static class Pipeline - { - Stage stage; - - // rest may be null - Pipeline rest; - EventConsumer next; - - Pipeline (Stage s) - { stage = s; } - - public String toString () - { - if (rest == null && next == null) - return stage.toString (); - if (rest != null) - return stage + " | " + rest; - throw new IllegalArgumentException ("next"); - } - - EventConsumer createPipeline () - throws IOException - { - if (next == null) { - if (rest == null) - next = stage.createStage (null); - else - next = stage.createStage (rest.createPipeline ()); - } - return next; - } - } - -/* - public static void main (String argv []) - { - try { - // three basic terminus cases - createPipeline ("null"); - createPipeline ("validate"); - createPipeline ("write ( stdout )"); - - // four basic filters - createPipeline ("nsfix | write ( stderr )"); - createPipeline ("wf | null"); - createPipeline ("null | null"); - createPipeline ( -"call ( http://www.example.com/services/xml-1a ) | xhtml ( stdout )"); - - // tee junctions - createPipeline ("tee ( validate ) | write ( stdout )"); - createPipeline ("tee ( nsfix | write ( stdout ) ) | validate"); - - // longer pipeline - createPipeline ("nsfix | tee ( validate ) | write ( stdout )"); - createPipeline ( - "null | wf | nsfix | tee ( validate ) | write ( stdout )"); - - // try some parsing error cases - try { - createPipeline ("null ("); // extra token '(' - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - - try { - createPipeline ("nsfix |"); // extra token '|' - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - - try { - createPipeline ("xhtml ( foo"); // missing right paren - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - - try { - createPipeline ("xhtml ( foo bar"); // required right paren - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - - try { - createPipeline ("tee ( nsfix | validate");// missing right paren - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - - // try some construction error cases - - try { - createPipeline ("call"); // missing param - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - try { - createPipeline ("call ( foobar )"); // broken param - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - try { - createPipeline ("nsfix ( foobar )"); // illegal param - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - try { - createPipeline ("null ( foobar )"); // illegal param - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - try { - createPipeline ("wf ( foobar )"); // illegal param - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - try { - createPipeline ("xhtml ( foobar.html )"); - new File ("foobar.html").delete (); - // now supported - } catch (Exception e) { - System.err.println ("** err: " + e.getMessage ()); } - try { - createPipeline ("xhtml"); // missing param - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - try { - createPipeline ("write ( stdout ) | null"); // nonterminal - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - try { - createPipeline ("validate | null"); - // now supported - } catch (Exception e) { - System.err.println ("** err: " + e.getMessage ()); } - try { - createPipeline ("validate ( foo )"); // illegal param - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - try { - createPipeline ("tee"); // missing param - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - try { - // only builtins so far - createPipeline ("com.example.xml.FilterClass"); - System.err.println ("** didn't report error"); - } catch (Exception e) { - System.err.println ("== err: " + e.getMessage ()); } - - } catch (Exception e) { - e.printStackTrace (); - } - } -/**/ - -} |