Java example source code file (DOMImplementationSourceImpl.java)

This example Java source code file (DOMImplementationSourceImpl.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

dom, domimplementation, domimplementationlistimpl, domimplementationsourceimpl, string, stringtokenizer, util, vector

The DOMImplementationSourceImpl.java Java example source code

/*
 * reserved comment block
 * DO NOT REMOVE OR ALTER!
 */
/*
 * Copyright 2001, 2002,2004 The Apache Software Foundation.
 *
 * Licensed 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 com.sun.org.apache.xerces.internal.dom;

import java.util.StringTokenizer;
import java.util.Vector;
import org.w3c.dom.DOMImplementationList;
import org.w3c.dom.DOMImplementationSource;
import org.w3c.dom.DOMImplementation;
import com.sun.org.apache.xerces.internal.dom.DOMImplementationListImpl;

/**
 * Supply one the right implementation, based upon requested features. Each
 * implemented <code>DOMImplementationSource object is listed in the
 * binding-specific list of available sources so that its
 * <code>DOMImplementation objects are made available.
 *
 * <p>See also the Document Object Model (DOM) Level 3 Core Specification.
 *
 * @xerces.internal
 *
 */
public class DOMImplementationSourceImpl
    implements DOMImplementationSource {

    /**
     * A method to request a DOM implementation.
     * @param features A string that specifies which features are required.
     *   This is a space separated list in which each feature is specified
     *   by its name optionally followed by a space and a version number.
     *   This is something like: "XML 1.0 Traversal Events 2.0"
     * @return An implementation that has the desired features, or
     *   <code>null if this source has none.
     */
    public DOMImplementation getDOMImplementation(String features) {
        // first check whether the CoreDOMImplementation would do
        DOMImplementation impl =
            CoreDOMImplementationImpl.getDOMImplementation();
        if (testImpl(impl, features)) {
            return impl;
        }
        // if not try the DOMImplementation
        impl = DOMImplementationImpl.getDOMImplementation();
        if (testImpl(impl, features)) {
            return impl;
        }

        return null;
    }

    /**
     * A method to request a list of DOM implementations that support the
     * specified features and versions, as specified in .
     * @param features A string that specifies which features and versions
     *   are required. This is a space separated list in which each feature
     *   is specified by its name optionally followed by a space and a
     *   version number. This is something like: "XML 3.0 Traversal +Events
     *   2.0"
     * @return A list of DOM implementations that support the desired
     *   features.
     */
    public DOMImplementationList getDOMImplementationList(String features) {
        // first check whether the CoreDOMImplementation would do
        DOMImplementation impl = CoreDOMImplementationImpl.getDOMImplementation();
                final Vector implementations = new Vector();
        if (testImpl(impl, features)) {
                        implementations.addElement(impl);
        }
        impl = DOMImplementationImpl.getDOMImplementation();
        if (testImpl(impl, features)) {
                        implementations.addElement(impl);
        }

        return new DOMImplementationListImpl(implementations);
    }

    boolean testImpl(DOMImplementation impl, String features) {

        StringTokenizer st = new StringTokenizer(features);
        String feature = null;
        String version = null;

        if (st.hasMoreTokens()) {
           feature = st.nextToken();
        }
        while (feature != null) {
           boolean isVersion = false;
           if (st.hasMoreTokens()) {
               char c;
               version = st.nextToken();
               c = version.charAt(0);
               switch (c) {
               case '0': case '1': case '2': case '3': case '4':
               case '5': case '6': case '7': case '8': case '9':
                   isVersion = true;
               }
           } else {
               version = null;
           }
           if (isVersion) {
               if (!impl.hasFeature(feature, version)) {
                   return false;
               }
               if (st.hasMoreTokens()) {
                   feature = st.nextToken();
               } else {
                   feature = null;
               }
           } else {
               if (!impl.hasFeature(feature, null)) {
                   return false;
               }
               feature = version;
           }
        }
        return true;
    }
}