001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements. See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership. The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the  "License");
007     * you may not use this file except in compliance with the License.
008     * You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    /*
019     * $Id: XMLStringFactory.java 468655 2006-10-28 07:12:06Z minchau $
020     */
021    package org.apache.xml.utils;
022    
023    /**
024     * A concrete class that implements this interface creates XMLString objects.
025     */
026    public abstract class XMLStringFactory
027    {
028    
029      /**
030       * Create a new XMLString from a Java string.
031       *
032       *
033       * @param string Java String reference, which must be non-null.
034       *
035       * @return An XMLString object that wraps the String reference.
036       */
037      public abstract XMLString newstr(String string);
038    
039      /**
040       * Create a XMLString from a FastStringBuffer.
041       *
042       *
043       * @param string FastStringBuffer reference, which must be non-null.
044       * @param start The start position in the array.
045       * @param length The number of characters to read from the array.
046       *
047       * @return An XMLString object that wraps the FastStringBuffer reference.
048       */
049      public abstract XMLString newstr(FastStringBuffer string, int start, 
050                                       int length);
051    
052      /**
053       * Create a XMLString from a FastStringBuffer.
054       *
055       *
056       * @param string FastStringBuffer reference, which must be non-null.
057       * @param start The start position in the array.
058       * @param length The number of characters to read from the array.
059       *
060       * @return An XMLString object that wraps the FastStringBuffer reference.
061       */
062      public abstract XMLString newstr(char[] string, int start, 
063                                       int length);
064                                       
065      /**
066       * Get a cheap representation of an empty string.
067       * 
068       * @return An non-null reference to an XMLString that represents "".
069       */
070      public abstract XMLString emptystr();
071    }