labelbureauresource.java

很棒的web服务器源代码

// LabelBureauResource.java
// $Id: LabelBureauResource.java,v 1.13 2000/08/16 21:37:43 ylafon Exp $
// (c) COPYRIGHT MIT and INRIA, 1996.
// Please first read the full copyright statement in file COPYRIGHT.html

package org.w3c.jigsaw.pics ;

import java.io.File;
import java.io.PrintStream;

import java.net.MalformedURLException;
import java.net.URL;

import org.w3c.tools.resources.Attribute;
import org.w3c.tools.resources.AttributeHolder;
import org.w3c.tools.resources.AttributeRegistry;
import org.w3c.tools.resources.BooleanAttribute;
import org.w3c.tools.resources.FileAttribute;
import org.w3c.tools.resources.FramedResource;
import org.w3c.tools.resources.Resource;
import org.w3c.tools.resources.StringArrayAttribute;

import org.w3c.www.http.HTTP;
import org.w3c.www.http.HttpEntityMessage;
import org.w3c.www.http.HttpMessage;

import org.w3c.jigsaw.forms.URLDecoder;
import org.w3c.jigsaw.forms.URLDecoderException;

import org.w3c.jigsaw.http.HTTPException;
import org.w3c.jigsaw.http.Reply;
import org.w3c.jigsaw.http.Request;

/**
 * An HTTP interface to query a Label bureau.
 * This conforms to the
 * <a href="http://www.w3.org/hypertext/WWW/PICS/labels.html">PICS 
 * protocol specification</a>.
 * <p>This entity defines the following parameter:</p>
 * <table border>
 * <caption>The list of parameters</caption>
 * <tr> 
 * <th align=left>Parameter name</th> 
 * <th align=left>Semantics</th>
 * <th align=left>Default value</th> 
 * <th align=left>Type</th>
 * </tr>
 * <tr> 
 * <th align=left>bureau</th> 
 * <th align=left>Name of the LabelBureau database</th>
 * <th align=left><em>none</em></th> 
 * <th align=left>java.lang.String</th>
 * </tr>
 * </table>
 * <p>This entity also inherits the parameters from the PostableResource.</p>
 */

public class LabelBureauResource extends FramedResource {

    /**
     * Attribute index - Our label bureau identifier.
     */
    protected static int ATTR_BUREAU_IDENTIFIER = -1 ;

    /**
     * Attribute index - Our label bureau identifier.
     */
    protected static int ATTR_BUREAU_SERVICES = -1 ;

    /**
     * Attribute index - debug flag.
     */
    protected static int ATTR_BUREAU_DEBUG = -1 ;

    static {
	Attribute   a = null ;
	Class     cls = null ;
	
	try {
	    cls = Class.forName("org.w3c.jigsaw.pics.LabelBureauResource");
	} catch (Exception ex) {
	    ex.printStackTrace() ;
	    System.exit(1) ;
	}
	// The bureau identifier (a file attribute):
	a = new FileAttribute("bureau"
			      , null
			      , Attribute.EDITABLE|Attribute.MANDATORY);
	ATTR_BUREAU_IDENTIFIER = AttributeRegistry.registerAttribute(cls, a) ;
	// The services ... to fix a IE bug with PICS :(
	a = new StringArrayAttribute("services",
				     null,
				     Attribute.EDITABLE);
	ATTR_BUREAU_SERVICES = AttributeRegistry.registerAttribute(cls, a) ;
	// The debug flag
	a = new BooleanAttribute("debug",
				 Boolean.FALSE,
				 Attribute.EDITABLE);
	ATTR_BUREAU_DEBUG = AttributeRegistry.registerAttribute(cls, a) ;
    }

    /**
     * Our loaded label bureau:
     */
    protected LabelBureauInterface bureau = null ;

    /**
     * Get our label bureau identifier.
     */

    public File getBureauIdentifier() {
	return (File) getValue(ATTR_BUREAU_IDENTIFIER, null) ;
    }

    /**
     * Get the service list
     */
    public String[] getServices() {
	return (String[]) getValue(ATTR_BUREAU_SERVICES, null);
    }

    /**
     *
     */
    public boolean getDebugFlag() {
	return getBoolean(ATTR_BUREAU_DEBUG, false);
    }

    /**
     * Check that we have loaded our bureau, or load it.
     */

    protected final void acquireBureau() {
	if ( bureau != null )
	    return ;
	File repository = getBureauIdentifier() ;
	if ( repository != null )
	    bureau = LabelBureauFactory.getLabelBureau(getBureauIdentifier()) ;
	return ;
    }

    /**
     * Build a PICS reply out of the given content.
     * @param request The request to reply to.
     * @param sb The StringBuffer containing the content to send back.
     */

    protected Reply makePICSReply (Request request, StringBuffer buffer) {
	String content = buffer.toString() ;
	Reply  reply   = request.makeReply(HTTP.OK) ;
	reply.setHeaderValue(reply.H_CONTENT_TYPE, PICS.APPLICATION_PICSLABEL);
	reply.setContent (content) ;
	if (getDebugFlag()) {
	    System.out.println("********* PICS REPLY *********");
	    System.out.println(content);
	    System.out.println("******************************");
	}
	return reply ;
    }

    protected Reply makePICSErrorReply(Request request, String msg) {
	Reply  reply   = request.makeReply(HTTP.OK) ;
	reply.setHeaderValue(reply.H_CONTENT_TYPE, PICS.APPLICATION_PICSLABEL);
	String content = "("+PICS.PICS_PROTOCOL_ID+" error "+
	    "("+msg+"))";
	reply.setContent(content);
	if (getDebugFlag()) {
	    System.out.println("********* PICS REPLY *********");
	    System.out.println(content);
	    System.out.println("******************************");
	}
	return reply;
    }

    /**
     * Get the generic labels for a set of service and a set of urls.
     * @param request the incomminmg request
     * @param format the pics format
     * @param urls the urls to label
     * @param services the services to ask
     * @param data the URLDecoder
     * @return A Reply instance
     * @exception HTTPException if processing the request failed.
     */
    protected Reply getGenericLabels (Request request,
				      int format,
				      String urls[],
				      String services[],
				      URLDecoder data) 
	throws HTTPException
    {
	StringBuffer sb = new StringBuffer (128) ;

	sb.append ("("+PICS.PICS_PROTOCOL_ID) ;
	// Go through each service:
    sloop:
	for (int is = 0; is < services.length ; is++) {
	    LabelServiceInterface s = bureau.getLabelService (services[is]) ;
	    if ( s == null ) {
		sb.append (" error " + "(no-ratings \"unknown service\")") ;
		continue sloop ;
	    }
	    s.dump (sb, format) ;
	    sb.append (" labels ") ;
	    try {
	    uloop:
		for (int iu = 0 ; iu < urls.length ; iu++) {
		    LabelInterface l = s.getGenericLabel (new URL(urls[iu])) ;
		    if ( l == null ) {
			sb.append (" error "+"(not-labeled \""+urls[iu]+"\")");
			continue uloop ;
		    }
		    if ( iu != 0 )
			sb.append (" ") ;
		    l.dump (sb, format) ;
		}
	    } catch (MalformedURLException e) {
		Reply error = request.makeReply(HTTP.BAD_REQUEST) ;
		error.setContent ("You are requesting an invalid URL,") ;
		throw new HTTPException (error) ;
	    }
	}
	sb.append (")") ;
	return makePICSReply (request, sb) ;
    }

    /**
     * Get the normal (generic or specific) labels.
     * @param request the incomminmg request
     * @param format the pics format
     * @param urls the urls to label
     * @param services the services to ask
     * @param data the URLDecoder
     * @return A Reply instance
     * @exception HTTPException if processing the request failed.
     */
    protected Reply getNormalLabels (Request request,
				     int format,
				     String urls[],
				     String services[],
				     URLDecoder data) 
	throws HTTPException
    {
	StringBuffer sb = new StringBuffer (128) ;

	sb.append ("("+PICS.PICS_PROTOCOL_ID) ;
	// Go through each service:
    sloop:
	for (int is = 0; is < services.length ; is++) {
	    LabelServiceInterface s = bureau.getLabelService (services[is]) ;
	    if ( s == null ) {
		sb.append (" error " + "(no-ratings \"unknown service\")") ;
		continue sloop ;
	    }
	    s.dump (sb, format) ;
	    sb.append (" labels ") ;
	    try {
	    uloop:
		for (int iu = 0 ; iu < urls.length ; iu++) {
		    URL            u = new URL (urls[iu]) ;
		    LabelInterface l = s.getSpecificLabel (u) ;
		    if ((l == null) && ((l = s.getGenericLabel(u)) == null)) {
			sb.append (" error "+"(not-labeled \""+urls[iu]+"\")");
			continue uloop ;
		    }
		    if (iu != 0)
			sb.append (" ") ;
		    l.dump (sb, format) ;
		}
	    } catch (MalformedURLException e) {
		Reply error = request.makeReply(HTTP.BAD_REQUEST) ;
		error.setContent ("You are requesting an invalid URL.") ;
		throw new HTTPException (error) ;
	    }
	}
	sb.append (")") ;
	return makePICSReply (request, sb) ;
    }

    /**
     * Get tree labels.
     * @param request the incomminmg request
     * @param format the pics format
     * @param urls the urls to label
     * @param services the services to ask
     * @param data the URLDecoder
     * @return A Reply instance
     * @exception HTTPException if processing the request failed.
     */
    protected Reply getTreeLabels (Request request,
				   int format,
				   String urls[],
				   String services[],
				   URLDecoder data) 
	throws HTTPException
    {
	StringBuffer sb = new StringBuffer (128) ;
	sb.append ("("+PICS.PICS_PROTOCOL_ID) ;
	// Go through each service:
    sloop:
	for (int is = 0; is < services.length ; is++) {
	    LabelServiceInterface s = bureau.getLabelService (services[is]) ;
	    if ( s == null ) {
		sb.append (" error " + "(no-ratings \"unknown service\")") ;
		continue sloop ;
	    }
	    s.dump (sb, format) ;
	    sb.append (" labels ") ;
	    try {
	      uloop:
		for (int iu = 0 ; iu < urls.length ; iu++) {
		    boolean spaced = false ;
		    LabelInterface l[] = s.getTreeLabels(new URL(urls[iu]));
		    if ( l == null ) {
			sb.append (" error "+"(not-labeled \""+urls[iu]+"\")");
			continue uloop ;
		    }
		    sb.append ((iu == 0) ? "(" : " (") ;
		    for (int il = 0 ; il < l.length ; il++) {
			if ( il != 0 )
			    sb.append (" ") ;
			l[il].dump (sb, format) ;
		    }
		    sb.append (")") ;
		}
	    } catch (MalformedURLException e) {
		Reply error = request.makeReply(HTTP.BAD_REQUEST) ;
		error.setContent ("You are requesting an invalid URL.") ;
		throw new HTTPException (error) ;
	    }
	}
	sb.append (")") ;
	return makePICSReply (request, sb) ;
    }

    /**
     * Get generic tree labels.
     * @param request the incomminmg request
     * @param format the pics format
     * @param urls the urls to label
     * @param services the services to ask
     * @param data the URLDecoder
     * @return A Reply instance
     * @exception HTTPException if processing the request failed.
     */

    protected Reply getGenericTreeLabels (Request request,
					  int format,
					  String urls[],
					  String services[],
					  URLDecoder data) 
	throws HTTPException
    {
	StringBuffer sb = new StringBuffer (128) ;
	sb.append ("("+PICS.PICS_PROTOCOL_ID) ;
	// Go through each service:
    sloop:
	for (int is = 0; is < services.length ; is++) {
	    LabelServiceInterface s = bureau.getLabelService (services[is]) ;
	    if ( s == null ) {
		sb.append (" error " + "(no-ratings \"unknown service\")") ;
		continue sloop ;
	    }
	    s.dump (sb, format) ;
	    sb.append (" labels ") ;
	    try {
	      uloop:
		for (int iu = 0 ; iu < urls.length ; iu++) {
		    URL u = new URL (urls[iu]) ;
		    LabelInterface l[] = s.getGenericTreeLabels(u) ;
		    if ( l == null ) {
			sb.append (" error "+"(not-labeled \""+urls[iu]+"\")");
			continue uloop ;
		    }
		    sb.append ((iu == 0) ? "(" : " (") ;
		    for (int il = 0 ; il < l.length ; il++) {
			if ( il != 0 )
			    sb.append (" ") ;
			l[il].dump (sb, format) ;
		    }
		    sb.append (")") ;
		}
	    } catch (MalformedURLException e) {
		Reply error = request.makeReply(HTTP.BAD_REQUEST) ;
		error.setContent ("You are requesting an invalid URL.") ;
		throw new HTTPException (error) ;
	    }

	}
	sb.append (")") ;
	return makePICSReply (request, sb) ;
    }

    public void setValue(int idx, Object value) {
	super.setValue(idx, value);
	if (idx == ATTR_BUREAU_DEBUG) {
	    PICS.setDebug(getDebugFlag());
	}
    }

    public void initialize(Object values[]) {
	super.initialize(values) ;
	acquireBureau() ;
	try {
	    registerFrameIfNone("org.w3c.jigsaw.pics.LabelBureauFrame",
				"label-bureau-frame");
	} catch (Exception ex) {
	    ex.printStackTrace();
	}
	PICS.setDebug(getDebugFlag());
    }

}