An Attributes implementation that can perform more operations than the attribute list helper supplied with the standard SAX2 distribution. : DOM Attribute « XML « Java






An Attributes implementation that can perform more operations than the attribute list helper supplied with the standard SAX2 distribution.

 
/*
 * 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.
 */

import org.xml.sax.Attributes;

/**
 * An Attributes implementation that can perform more operations than the
 * attribute list helper supplied with the standard SAX2 distribution.
 */
public class AttributesImpl implements Attributes {

  //
  // Data
  //

  /** Head node. */
  private ListNode head;

  /** Tail node. */
  private ListNode tail;

  /** Length. */
  private int length;

  //
  // Attributes methods
  //

  /** Returns the number of attributes. */
  public int getLength() {
    return length;
  }

  /** Returns the index of the specified attribute. */
  public int getIndex(String raw) {
    ListNode place = head;
    int index = 0;
    while (place != null) {
      if (place.raw.equals(raw)) {
        return index;
      }
      index++;
      place = place.next;
    }
    return -1;
  }

  /** Returns the index of the specified attribute. */
  public int getIndex(String uri, String local) {
    ListNode place = head;
    int index = 0;
    while (place != null) {
      if (place.uri.equals(uri) && place.local.equals(local)) {
        return index;
      }
      index++;
      place = place.next;
    }
    return -1;
  }

  /** Returns the attribute URI by index. */
  public String getURI(int index) {

    ListNode node = getListNodeAt(index);
    return node != null ? node.uri : null;

  } // getURI(int):String

  /** Returns the attribute local name by index. */
  public String getLocalName(int index) {

    ListNode node = getListNodeAt(index);
    return node != null ? node.local : null;

  } // getLocalName(int):String

  /** Returns the attribute raw name by index. */
  public String getQName(int index) {

    ListNode node = getListNodeAt(index);
    return node != null ? node.raw : null;

  } // getQName(int):String

  /** Returns the attribute type by index. */
  public String getType(int index) {

    ListNode node = getListNodeAt(index);
    return (node != null) ? node.type : null;

  } // getType(int):String

  /** Returns the attribute type by uri and local. */
  public String getType(String uri, String local) {

    ListNode node = getListNode(uri, local);
    return (node != null) ? node.type : null;

  } // getType(String,String):String

  /** Returns the attribute type by raw name. */
  public String getType(String raw) {

    ListNode node = getListNode(raw);
    return (node != null) ? node.type : null;

  } // getType(String):String

  /** Returns the attribute value by index. */
  public String getValue(int index) {

    ListNode node = getListNodeAt(index);
    return (node != null) ? node.value : null;

  } // getType(int):String

  /** Returns the attribute value by uri and local. */
  public String getValue(String uri, String local) {

    ListNode node = getListNode(uri, local);
    return (node != null) ? node.value : null;

  } // getType(String):String

  /** Returns the attribute value by raw name. */
  public String getValue(String raw) {

    ListNode node = getListNode(raw);
    return (node != null) ? node.value : null;

  } // getType(String):String

  //
  // Public methods
  //

  /** Adds an attribute. */
  public void addAttribute(String raw, String type, String value) {
    addAttribute(null, null, raw, type, value);
  }

  /** Adds an attribute. */
  public void addAttribute(String uri, String local, String raw, String type, String value) {

    ListNode node = new ListNode(uri, local, raw, type, value);
    if (length == 0) {
      head = node;
    } else {
      tail.next = node;
    }
    tail = node;
    length++;

  } // addAttribute(String,StringString,String,String)

  /** Inserts an attribute. */
  public void insertAttributeAt(int index, String raw, String type, String value) {
    insertAttributeAt(index, null, null, raw, type, value);
  }

  /** Inserts an attribute. */
  public void insertAttributeAt(int index, String uri, String local, String raw, String type,
      String value) {

    // if list is empty, add attribute
    if (length == 0 || index >= length) {
      addAttribute(uri, local, raw, type, value);
      return;
    }

    // insert at beginning of list
    ListNode node = new ListNode(uri, local, raw, type, value);
    if (index < 1) {
      node.next = head;
      head = node;
    } else {
      ListNode prev = getListNodeAt(index - 1);
      node.next = prev.next;
      prev.next = node;
    }
    length++;

  } // insertAttributeAt(int,String,String,String,String,String)

  /** Removes an attribute. */
  public void removeAttributeAt(int index) {

    if (length == 0) {
      return;
    }

    if (index == 0) {
      head = head.next;
      if (head == null) {
        tail = null;
      }
      length--;
    } else {
      ListNode prev = getListNodeAt(index - 1);
      ListNode node = getListNodeAt(index);
      if (node != null) {
        prev.next = node.next;
        if (node == tail) {
          tail = prev;
        }
        length--;
      }
    }

  } // removeAttributeAt(int)

  /** Removes the specified attribute. */
  public void removeAttribute(String raw) {
    removeAttributeAt(getIndex(raw));
  }

  /** Removes the specified attribute. */
  public void removeAttribute(String uri, String local) {
    removeAttributeAt(getIndex(uri, local));
  }

  //
  // Private methods
  //

  /** Returns the node at the specified index. */
  private ListNode getListNodeAt(int i) {

    for (ListNode place = head; place != null; place = place.next) {
      if (--i == -1) {
        return place;
      }
    }

    return null;

  } // getListNodeAt(int):ListNode

  /** Returns the first node with the specified uri and local. */
  public ListNode getListNode(String uri, String local) {

    if (uri != null && local != null) {
      ListNode place = head;
      while (place != null) {
        if (place.uri != null && place.local != null && place.uri.equals(uri)
            && place.local.equals(local)) {
          return place;
        }
        place = place.next;
      }
    }
    return null;

  } // getListNode(String,String):ListNode

  /** Returns the first node with the specified raw name. */
  private ListNode getListNode(String raw) {

    if (raw != null) {
      for (ListNode place = head; place != null; place = place.next) {
        if (place.raw != null && place.raw.equals(raw)) {
          return place;
        }
      }
    }

    return null;

  } // getListNode(String):ListNode

  //
  // Object methods
  //

  /** Returns a string representation of this object. */
  public String toString() {
    StringBuffer str = new StringBuffer();

    str.append('[');
    str.append("len=");
    str.append(length);
    str.append(", {");
    for (ListNode place = head; place != null; place = place.next) {
      str.append(place.toString());
      if (place.next != null) {
        str.append(", ");
      }
    }
    str.append("}]");

    return str.toString();

  } // toString():String

  //
  // Classes
  //

  /**
   * An attribute node.
   */
  static class ListNode {

    //
    // Data
    //

    /** Attribute uri. */
    public String uri;

    /** Attribute local. */
    public String local;

    /** Attribute raw. */
    public String raw;

    /** Attribute type. */
    public String type;

    /** Attribute value. */
    public String value;

    /** Next node. */
    public ListNode next;

    //
    // Constructors
    //

    /** Constructs a list node. */
    public ListNode(String uri, String local, String raw, String type, String value) {

      this.uri = uri;
      this.local = local;
      this.raw = raw;
      this.type = type;
      this.value = value;

    } // <init>(String,String,String,String,String)

    //
    // Object methods
    //

    /** Returns string representation of this object. */
    public String toString() {
      return raw != null ? raw : local;
    }

  } // class ListNode

} // class AttributesImpl

   
  








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