filedircontext.java

业界著名的tomcat服务器的最新6.0的源代码。

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


package org.apache.naming.resources;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.Hashtable;

import javax.naming.NameAlreadyBoundException;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.OperationNotSupportedException;
import javax.naming.directory.Attributes;
import javax.naming.directory.DirContext;
import javax.naming.directory.ModificationItem;
import javax.naming.directory.SearchControls;

import org.apache.naming.NamingContextBindingsEnumeration;
import org.apache.naming.NamingContextEnumeration;
import org.apache.naming.NamingEntry;

/**
 * Filesystem Directory Context implementation helper class.
 *
 * @author Remy Maucherat
 * @version $Revision: 467222 $ $Date: 2006-10-24 05:17:11 +0200 (mar., 24 oct. 2006) $
 */

public class FileDirContext extends BaseDirContext {

    private static org.apache.juli.logging.Log log=
        org.apache.juli.logging.LogFactory.getLog( FileDirContext.class );

    // -------------------------------------------------------------- Constants


    /**
     * The descriptive information string for this implementation.
     */
    protected static final int BUFFER_SIZE = 2048;


    // ----------------------------------------------------------- Constructors


    /**
     * Builds a file directory context using the given environment.
     */
    public FileDirContext() {
        super();
    }


    /**
     * Builds a file directory context using the given environment.
     */
    public FileDirContext(Hashtable env) {
        super(env);
    }


    // ----------------------------------------------------- Instance Variables


    /**
     * The document base directory.
     */
    protected File base = null;


    /**
     * Absolute normalized filename of the base.
     */
    protected String absoluteBase = null;


    /**
     * Case sensitivity.
     */
    protected boolean caseSensitive = true;


    /**
     * Allow linking.
     */
    protected boolean allowLinking = false;


    // ------------------------------------------------------------- Properties


    /**
     * Set the document root.
     *
     * @param docBase The new document root
     *
     * @exception IllegalArgumentException if the specified value is not
     *  supported by this implementation
     * @exception IllegalArgumentException if this would create a
     *  malformed URL
     */
    public void setDocBase(String docBase) {

    // Validate the format of the proposed document root
    if (docBase == null)
        throw new IllegalArgumentException
        (sm.getString("resources.null"));

    // Calculate a File object referencing this document base directory
    base = new File(docBase);
        try {
            base = base.getCanonicalFile();
        } catch (IOException e) {
            // Ignore
        }

    // Validate that the document base is an existing directory
    if (!base.exists() || !base.isDirectory() || !base.canRead())
        throw new IllegalArgumentException
        (sm.getString("fileResources.base", docBase));
        this.absoluteBase = base.getAbsolutePath();
        super.setDocBase(docBase);

    }


    /**
     * Set case sensitivity.
     */
    public void setCaseSensitive(boolean caseSensitive) {
        this.caseSensitive = caseSensitive;
    }


    /**
     * Is case sensitive ?
     */
    public boolean isCaseSensitive() {
        return caseSensitive;
    }


    /**
     * Set allow linking.
     */
    public void setAllowLinking(boolean allowLinking) {
        this.allowLinking = allowLinking;
    }


    /**
     * Is linking allowed.
     */
    public boolean getAllowLinking() {
        return allowLinking;
    }


    // --------------------------------------------------------- Public Methods


    /**
     * Release any resources allocated for this directory context.
     */
    public void release() {
        super.release();
    }


    // -------------------------------------------------------- Context Methods


    /**
     * Retrieves the named object.
     *
     * @param name the name of the object to look up
     * @return the object bound to name
     * @exception NamingException if a naming exception is encountered
     */
    public Object lookup(String name)
        throws NamingException {
        Object result = null;
        File file = file(name);

        if (file == null)
            throw new NamingException
                (sm.getString("resources.notFound", name));

        if (file.isDirectory()) {
            FileDirContext tempContext = new FileDirContext(env);
            tempContext.setDocBase(file.getPath());
            tempContext.setAllowLinking(getAllowLinking());
            tempContext.setCaseSensitive(isCaseSensitive());
            result = tempContext;
        } else {
            result = new FileResource(file);
        }

        return result;

    }


    /**
     * Unbinds the named object. Removes the terminal atomic name in name
     * from the target context--that named by all but the terminal atomic
     * part of name.
     * <p>
     * This method is idempotent. It succeeds even if the terminal atomic
     * name is not bound in the target context, but throws
     * NameNotFoundException if any of the intermediate contexts do not exist.
     *
     * @param name the name to bind; may not be empty
     * @exception NameNotFoundException if an intermediate context does not
     * exist
     * @exception NamingException if a naming exception is encountered
     */
    public void unbind(String name)
        throws NamingException {

        File file = file(name);

        if (file == null)
            throw new NamingException
                (sm.getString("resources.notFound", name));

        if (!file.delete())
            throw new NamingException
                (sm.getString("resources.unbindFailed", name));

    }


    /**
     * Binds a new name to the object bound to an old name, and unbinds the
     * old name. Both names are relative to this context. Any attributes
     * associated with the old name become associated with the new name.
     * Intermediate contexts of the old name are not changed.
     *
     * @param oldName the name of the existing binding; may not be empty
     * @param newName the name of the new binding; may not be empty
     * @exception NameAlreadyBoundException if newName is already bound
     * @exception NamingException if a naming exception is encountered
     */
    public void rename(String oldName, String newName)
        throws NamingException {

        File file = file(oldName);

        if (file == null)
            throw new NamingException
                (sm.getString("resources.notFound", oldName));

        File newFile = new File(base, newName);

        file.renameTo(newFile);

    }


    /**
     * Enumerates the names bound in the named context, along with the class
     * names of objects bound to them. The contents of any subcontexts are
     * not included.
     * <p>
     * If a binding is added to or removed from this context, its effect on
     * an enumeration previously returned is undefined.
     *
     * @param name the name of the context to list
     * @return an enumeration of the names and class names of the bindings in
     * this context. Each element of the enumeration is of type NameClassPair.
     * @exception NamingException if a naming exception is encountered
     */
    public NamingEnumeration list(String name)
        throws NamingException {

        File file = file(name);

        if (file == null)
            throw new NamingException
                (sm.getString("resources.notFound", name));

        return new NamingContextEnumeration(list(file).iterator());

    }


    /**
     * Enumerates the names bound in the named context, along with the
     * objects bound to them. The contents of any subcontexts are not
     * included.
     * <p>
     * If a binding is added to or removed from this context, its effect on
     * an enumeration previously returned is undefined.
     *
     * @param name the name of the context to list
     * @return an enumeration of the bindings in this context.
     * Each element of the enumeration is of type Binding.
     * @exception NamingException if a naming exception is encountered
     */
    public NamingEnumeration listBindings(String name)
        throws NamingException {

        File file = file(name);

        if (file == null)
            throw new NamingException
                (sm.getString("resources.notFound", name));

        return new NamingContextBindingsEnumeration(list(file).iterator(),
                this);

    }


    /**
     * Destroys the named context and removes it from the namespace. Any
     * attributes associated with the name are also removed. Intermediate
     * contexts are not destroyed.
     * <p>
     * This method is idempotent. It succeeds even if the terminal atomic
     * name is not bound in the target context, but throws
     * NameNotFoundException if any of the intermediate contexts do not exist.
     *
     * In a federated naming system, a context from one naming system may be
     * bound to a name in another. One can subsequently look up and perform
     * operations on the foreign context using a composite name. However, an
     * attempt destroy the context using this composite name will fail with
     * NotContextException, because the foreign context is not a "subcontext"
     * of the context in which it is bound. Instead, use unbind() to remove
     * the binding of the foreign context. Destroying the foreign context
     * requires that the destroySubcontext() be performed on a context from
     * the foreign context's "native" naming system.
     *
     * @param name the name of the context to be destroyed; may not be empty
     * @exception NameNotFoundException if an intermediate context does not
     * exist
     * @exception NotContextException if the name is bound but does not name
     * a context, or does not name a context of the appropriate type
     */
    public void destroySubcontext(String name)
        throws NamingException {
        unbind(name);
    }


    /**
     * Retrieves the named object, following links except for the terminal
     * atomic component of the name. If the object bound to name is not a
     * link, returns the object itself.
     *
     * @param name the name of the object to look up
     * @return the object bound to name, not following the terminal link
     * (if any).
     * @exception NamingException if a naming exception is encountered