plainremoteresource.java

很棒的web服务器源代码

// PlainRemoteResource.java
// $Id: PlainRemoteResource.java,v 1.31 2000/08/16 21:37:34 ylafon Exp $
// (c) COPYRIGHT MIT and INRIA, 1997.
// Please first read the full copyright statement in file COPYRIGHT.html

package org.w3c.jigsaw.admin;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;

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

import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

import org.w3c.tools.resources.Attribute;
import org.w3c.tools.resources.SimpleAttribute;
import org.w3c.tools.resources.ArrayAttribute;

import org.w3c.tools.resources.serialization.AttributeDescription;
import org.w3c.tools.resources.serialization.EmptyDescription;
import org.w3c.tools.resources.serialization.ResourceDescription;

import org.w3c.www.protocol.http.HttpManager;
import org.w3c.www.protocol.http.Reply;
import org.w3c.www.protocol.http.Request;

public class PlainRemoteResource implements RemoteResource {
    private static final boolean debug = false;
    /**
     * The client side admin context
     */
    protected AdminContext admin = null;
    /**
     * The remote resource set of attributes.
     */
    protected AttributeDescription attributes[];
    /**
     * The remote resource attribute values.
     */
    protected Object values[] = null;
    /**
     * Is that resource a container resource ?
     */
    protected boolean iscontainer = false;
    /**
     * Is that resource a indexers catalog ?
     */
    protected boolean isindexerscatalog = false;
    /**
     * Is that resource a directory resource ?
     */
    protected boolean isDirectoryResource = false;
    /**
     * Is that resource a framed resource ?
     */
    protected boolean isframed = false;
    /**
     * The name of that resource (ie it's identifier attribute).
     */
    protected String identifier = null;
    /**
     * The name of the parent of that resource, as an URL.
     */
    protected URL parent = null;
    /**
     * The admin URL for the wrapped resource.
     */
    protected URL url = null;
    /**
     * Set of attached frames.
     */
    protected RemoteResource frames[] = null;
    /**
     * Our description
     */
    protected ResourceDescription description = null;

    protected Request createRequest() {
	Request request = admin.http.createRequest();
	request.setURL(url);
	if (!debug) {
	    request.setValue("TE", "gzip");
	}
	return request;
    }

    protected InputStream getInputStream(Reply reply) 
	throws IOException
    {
	if (reply.hasTransferEncoding("gzip"))
	    return new GZIPInputStream(reply.getInputStream());
	else
	    return reply.getInputStream();	
    }

    protected void setFrames(RemoteResource frames[]) {
	this.isframed  = true;
	this.frames    = frames;
    }

    /**
     * Get the target resource class hierarchy.
     * This method will return the class hierarchy as an array of String. The
     * first string in the array is the name of the resource class itself, the
     * last string will always be <em>java.lang.Object</em>.
     * @return A String array givimg the target resource's class description.
     * @exception RemoteAccessException If somenetwork failure occured.
     */

    public String[] getClassHierarchy()
	throws RemoteAccessException
    {
	return description.getClassHierarchy();
    }

    /**
     * Reindex the resource's children if this resource is a DirectoryResource.
     * @exception RemoteAccessException If it's not a DirectoryResource
     */
    public void reindex(boolean rec)
	throws RemoteAccessException
    {
	if (isDirectoryResource()) {
	    try {
		Request req = createRequest();
		// Prepare the request:
		if (rec) {
		    req.setMethod("REINDEX-RESOURCE");
		} else {
		    req.setMethod("REINDEX-LOCALLY");
		}
		// Run it:
		Reply rep = admin.runRequest(req);
	    } catch (RemoteAccessException rae) {
		throw rae;
	    } catch (Exception ex) {
		ex.printStackTrace();
		throw new RemoteAccessException(ex.getMessage());
	    }
	} else {
	    throw new RemoteAccessException("Error, can't reindex! This is "+
					    "not a DirectoryResource.");
	}
    }

    /**
     * Delete that resource, and detach it from its container.
     * @exception RemoteAccessException If somenetwork failure occured.
     */
    public void delete()
	throws RemoteAccessException
    {
	try {
	    Request req = createRequest();
	    // Prepare the request:
	    req.setMethod("DELETE-RESOURCE");
	    // Run it:
	    Reply rep = admin.runRequest(req);
	} catch (RemoteAccessException rae) {
	    throw rae;
	} catch (Exception ex) {
	    ex.printStackTrace();
	    throw new RemoteAccessException(ex.getMessage());
	}
    }

    /**
     * Get the target resource list of attributes.
     * This method returns the target resource attributes description. The
     * resulting array contains instances of the Attribute class, one item
     * per described attributes.
     * <p>Even though this returns all the attribute resources, only the
     * ones that are advertized as being editable can be set through this
     * interface.
     * @return An array of Attribute.
     * @exception RemoteAccessException If somenetwork failure occured.
     */
    public synchronized AttributeDescription[] getAttributes()
	throws RemoteAccessException
    {
	return description.getAttributeDescriptions();
    }

    /**
     * @param name The attribute whose value is to be fetched, encoded as
     * its name.
     * @exception RemoteAccessException If somenetwork failure occured.
     */

    public Object getValue(String attr)
	throws RemoteAccessException
    {
	if (attr.equals("identifier")) {
	    return identifier;
	}
	String attrs[] = new String[1];
	attrs[0] = attr;
	return getValues(attrs)[0];
    }

    protected AttributeDescription lookupAttribute(String name) {
	AttributeDescription attds[] = description.getAttributeDescriptions();
	for (int i = 0 ; i < attds.length ; i++) {
	    AttributeDescription ad = attds[i];
	    if (ad.getName().equals(name))
		return ad;
	}
	return null;
    }

    /**
     * @param attrs The (ordered) set of attributes whose value is to be
     * fetched.
     * @return An (ordered) set of values, one per queried attribute.
     * @exception RemoteAccessException If somenetwork failure occured.
     */
    public Object[] getValues(String attrs[])
	throws RemoteAccessException
    {
	Object values[] = new Object[attrs.length];
	for (int i = 0 ; i < attrs.length ; i++) {
	    AttributeDescription ad = lookupAttribute(attrs[i]);
	    if (ad != null) {
		values[i] = ad.getValue();
	    } else {
		values[i] = null;
	    }
	}
	return values;
    }

    /**
     * @param attr The attribute to set, encoded as it's name.
     * @param value The new value for that attribute.
     * @exception RemoteAccessException If somenetwork failure occured.
     */

    public void setValue(String attr, Object value)
	throws RemoteAccessException
    {
	String attrs[] = new String[1];
	Object vals[] = new Object[1];
	attrs[0] = attr;
	vals[0] = value;
	setValues(attrs, vals);
    }

    /**
     * Set a set of attribute values in one shot.
     * This method guarantees that either all setting is done, or none of
     * them are.
     * @param attrs The (ordered) list of attribute to set, encoded as their
     * names.
     * @param values The (ordered) list of values, for each of the above
     * attributes.
     * @exception RemoteAccessException If somenetwork failure occured.
     */
    public void setValues(String names[], Object values[])
	throws RemoteAccessException
    {
	String  newId  = null;
	boolean change = false;

	AttributeDescription attrs[] = new AttributeDescription[names.length];

	for (int i = 0 ; i < names.length ; i++) {
	    AttributeDescription ad = lookupAttribute(names[i]);
	    if (ad != null) {
		ad.setValue(values[i]);
		attrs[i] = ad;
	    }
	    if (names[i].equals("identifier")) {
		change = true;
		newId = (String) values[i];
	    }
	}

	ResourceDescription descr = description.getClone(attrs);

	try {
	    ByteArrayOutputStream bout = new ByteArrayOutputStream();
	    OutputStream out;
	    if (debug) {
		out = bout;
	    } else {
		out = new GZIPOutputStream(bout);
	    }
	    admin.writer.writeResourceDescription(descr, out);
	    byte bits[] = bout.toByteArray();

	    Request req = createRequest();
	    req.setMethod("SET-VALUES");
	    req.setContentType(admin.conftype);
	    req.setContentLength(bits.length);
	    if (!debug) {
		req.addTransferEncoding("gzip");
	    }
	    req.setOutputStream(new ByteArrayInputStream(bits));
	
	    // Run that request:
	    Reply rep = admin.runRequest(req);
	} catch (RemoteAccessException rae) {
	    throw rae;
	} catch (Exception ex) {
	    ex.printStackTrace();
	    throw new RemoteAccessException("exception "+ex.getMessage());
	}

	if(change) {
	    identifier = new String(newId);
	    try {
		//if (parent != null) {
		if (! isFrame()) {
		    if (iscontainer)
			url = new URL(parent.toString()+identifier+"/");
		    else 
			url = new URL(parent.toString()+identifier);
		    // update frames url
		    updateURL(new URL(parent.toString()+identifier));
		} else {
		    String oldFile = url.getFile();
		    int index = oldFile.lastIndexOf('?');
		    String newFile = oldFile.substring(0, index);
		    updateURL(new URL(url, newFile));
		}
	    } catch (MalformedURLException ex) {
		ex.printStackTrace();
	    }
	}
	return;
    }

    public void updateURL(URL parentURL) {
	if ( isFrame() ) {
	    try {
		url = new URL(parentURL, parentURL.getFile()+"?"+identifier);
	    } catch (MalformedURLException ex) {
		return;
	    }
	}
	//update frames URLs
	if (frames != null) {
	    for(int i=0 ; i < frames.length ; i++) {
		frames[i].updateURL(url);
	    }
	}
    }

    /**
     * @exception RemoteAccessException If somenetwork failure occured.
     */

    public boolean isContainer()
	throws RemoteAccessException
    {
	// a Hack to avoid multiple sub-trees under the main root resource
	if(identifier != null) {
	    if(identifier.equals("root"))
		return false;
	    if(identifier.equals("control")) {
		String classname = getClassHierarchy()[0];
		if(classname.equals("org.w3c.jigsaw.http.ControlResource"))
		    return false;
	    }
	}
	return iscontainer;
    }

    /**
     * @exception RemoteAccessException If somenetwork failure occured.
     */

    public boolean isIndexersCatalog()
	throws RemoteAccessException
    {
	return isindexerscatalog;
    }

    /**
     * Is is a DirectoryResource
     * @exception RemoteAccessException If somenetwork failure occured.
     */
    public boolean isDirectoryResource()
	throws RemoteAccessException
    {
	if(identifier != null) {
	    if(identifier.equals("root"))
		return false;
	}
	return isDirectoryResource;
    }

    /**
     * @exception RemoteAccessException If somenetwork failure occured.
     */
    public String[] enumerateResourceIdentifiers()
	throws RemoteAccessException
    {
	if ( ! iscontainer )
	    throw new RuntimeException("not a container");
	try {
	    update();
	    return description.getChildren();
	} catch (Exception ex) {