ConfigElement.java

package org.springframework.extensions.config;

/*
 * ConfigElement.java
 *
 * Copyright (c) 2007 Starlasoft. All rights reserved.
 */

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * Configuration Element Class
 * 
 * <p>The methods must match the methods of the ConfigElement interface in the Alfresco code.
 */
public class ConfigElement {

  //  Element name and value
  
  private String m_name;
  private String m_value;
  
  //  Attributes
  
  private Map<String, String> m_attributes;

  //  Children
  
  private List<ConfigElement> m_children;
  
  /**
   * Class constructor
   * 
   * @param name String
   * @param value String
   */
  public ConfigElement( String name, String value) {
    m_name  = name;
    m_value = value;
  }
  
  /**
   * Returns the name of this config element
   * 
   * @return Name of this config element
   */
  public String getName() {
    return m_name;
  }

  /**
   * Gets the value of the attribute with the given name
   * 
   * @param name
   *            The name of the attribute to get the value for
   * @return The value of the attrbiute or null if the attribute doesn't exist
   */
  public String getAttribute(String name) {
    if ( m_attributes == null)
      return null;
    return m_attributes.get( name);
  }

  /**
   * Returns the list of attributes held by this config element
   * 
   * @return The list of attributes
   */
  public Map<String, String> getAttributes() {
    return m_attributes;
  }

  /**
   * Determines whether the config element has the named attribute
   * 
   * @param name
   *            Name of the attribute to check existence for
   * @return true if it exists, false otherwise
   */
  public boolean hasAttribute(String name) {
    if ( m_attributes != null)
      return m_attributes.containsKey( name);
    return false;
  }

  /**
   * Returns the number of attributes this config element has
   * 
   * @return The number of attributes
   */
  public int getAttributeCount() {
    if ( m_attributes != null)
      return m_attributes.size();
    return 0;
  }
  
  /**
   * Gets the value of this config element. If this config element has
   * children then this method may return null
   * 
   * @return Value of this config element or null if there is no value
   */
  public String getValue() {
    return m_value;
  }

  /**
   * Returns a child config element of the given name 
   * 
   * @param name The name of the config element to retrieve
   * @return The ConfigElement or null if it does not exist
   */
  public ConfigElement getChild(String name) {
    if ( m_children != null) {
      for ( ConfigElement child : m_children) {
        if ( child.getName().equals( name))
          return child;
      }
    }
    return null;
  }
  
  /**
   * Returns a list of children held by this ConfigElement
   * 
   * @return The list of children.
   */
  public List<ConfigElement> getChildren() {
    return m_children;
  }

  /**
   * Determines whether this config element has any children. It is more
   * effecient to call this method rather than getChildren().size() as a
   * collection is not created if it is not required
   * 
   * @return true if it has children, false otherwise
   */
  public boolean hasChildren() {
    if ( m_children == null)
      return false;
    return m_children.size() > 0 ? true : false;
  }

  /**
   * Returns the number of children this config element has
   * 
   * @return The number of children
   */
  public int getChildCount() {
    if ( m_children != null)
      return m_children.size();
    return 0;
  }
  
  /**
   * Combines the given config element with this config element and returns a
   * new instance containing the resulting combination. The combination of the
   * two objects MUST NOT change this instance.
   * 
   * @param configElement
   *            The config element to combine into this one
   * @return The combined ConfigElement
   */
  public ConfigElement combine(ConfigElement configElement) {
    return null;
  }
  
  /**
   * Set the element name
   * 
   * @param name String
   */
  public void setName( String name) {
    m_name = name;
  }
  
  /**
   * Set the value
   * 
   * @param value String
   */
  public void setValue( String value) {
    m_value = value;
  }
  
  /**
   * Add an attribute
   * 
   * @param attrName String
   * @param attrVal String
   */
  public void addAttribute( String attrName, String attrVal) {
    if ( m_attributes == null)
      m_attributes = new HashMap<String, String>();
    m_attributes.put( attrName, attrVal);
  }
  
  /**
   * Add a child element
   * 
   * @param child ConfigElement
   */
  public void addChild( ConfigElement child) {
    if ( m_children == null)
      m_children = new ArrayList<ConfigElement>();
    m_children.add( child);
  }
  
  /**
   * Return the configuration element as a string
   * 
   * @return String
   */
  public String toString() {
    StringBuilder str = new StringBuilder();
    
    str.append( "[");
    str.append( getName());
    str.append( "=");
    str.append( getValue());
    str.append( ",Attrs=");
    str.append( getAttributeCount());
    str.append( ",Children=");
    str.append( getChildCount());
    str.append( "]");
    
    return str.toString();
  }
}