archive/releng.builder/tools/apitools/org.eclipse.wtp.releng.tools.component.core/src/org/eclipse/wtp/releng/tools/component/internal/Location.java

/*******************************************************************************
 * Copyright (c) 2002, 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.wtp.releng.tools.component.internal;

import java.io.File;
import org.eclipse.wtp.releng.tools.component.ILocation;
import org.eclipse.wtp.releng.tools.component.ILocationChildrenIterator;
import org.eclipse.wtp.releng.tools.component.ILocationVisitor;

/**
 * The <code>Location</code> class is a concrete implementation of the
 * <code>ILocation</code> interface. It provides a static convienience method
 * for creating new <code>Location</code> objects.
 * <p>
 * Note that all locations use '/' as their file separator.
 */
public abstract class Location implements ILocation
{
  protected ILocation parent;
  protected String name;

  /**
   * Creates a new <code>Location</code> with the given parent and the given
   * name
   * 
   * @param parent
   *          The parent location, can be <code>null</code>
   * @param fullName
   *          The name of this location, cannot be <code>null</code> s
   */
  public Location(ILocation parent, String fullName)
  {
    this.parent = parent;
    this.name = fullName.replace('\\', '/');
  }

  /*
   * @see com.example.location.ILocation#accept(com.example.location.ILocationVisitor)
   */
  public void accept(ILocationVisitor visitor)
  {
    if (visitor.accept(this))
    {
      if (hasChildren())
      {
        ILocationChildrenIterator i = childIterator();
        ILocation child = i.next();
        while (child != null)
        {
          child.accept(visitor);
          child = i.next();
        }
      }
    }
  }

  /*
   * @see com.example.location.ILocation#getParent()
   */
  public ILocation getParent()
  {
    return parent;
  }

  /*
   * @see com.example.location.ILocation#getName()
   */
  public String getName()
  {
    return name;
  }

  /**
   * Creates a new location from a file. Clients can create locations on
   * directories or archive files (jar, zip, war, ear).
   * 
   * @param file
   *          The file to wrap, not <code>null</code>
   * @return ILocation The resulting location, can be <code>null</code> if the
   *         file does not exist, is not a directory, or is not an archive.
   */
  public static ILocation createLocation(File file)
  {
    if (!file.exists())
    {
      return null;
    }
    if (file.isDirectory())
    {
      return new FileLocation(file);
    }
    if (isArchive(file.getAbsolutePath()))
    {
      return new ZipLocation(file);
    }
    return new FileLocation(file);
  }

  /**
   * Answers <code>true</code> if the path ends in ".jar", ".zip", ".ear", or
   * ".war".
   * <p>
   * This code has been optimized to within an inch of its life.
   * 
   * @param path
   *          The path of the file
   * @return boolean <code>true</code> if the path represents a jar, zip, ear,
   *         or war file.
   */
  public static boolean isArchive(String path)
  {
    if (path == null)
      return false;
    if (path.length() < 5)
      return false;
    int index = path.length() - 1;
    char extChar = path.charAt(index--);
    switch (extChar)
    {
      case 'p' :
      case 'P' :
        if (path.endsWith(".zip"))
        {
          return true;
        }
        break;
      case 'r' :
      case 'R' :
        extChar = path.charAt(index--);
        switch (extChar)
        {
          case 'a' :
          case 'A' :
            extChar = path.charAt(index--);
            switch (extChar)
            {
              case 'j' :
              case 'J' :
                if (path.charAt(index) == '.')
                {
                  return true;
                }
                break;
              case 'w' :
              case 'W' :
                if (path.charAt(index) == '.')
                {
                  return true;
                }
                break;
              case 'e' :
              case 'E' :
                if (path.charAt(index) == '.')
                {
                  return true;
                }
                break;
            }
        }
        break;
    }
    return false;
  }

  /**
   * Answers the extension of the given path. An extension is normally a three
   * character addition to the end of a filename separated from the filename by
   * the '.' character.
   * 
   * @param path
   *          a file path, not <code>null</code>
   * @return String the extension of the path
   */
  public static String getExtension(String path)
  {
    int index = path.lastIndexOf('.');
    if (index < 0)
      return "";
    return path.substring(index + 1).toLowerCase();
  }

  /*
   * @see java.lang.Object#equals(java.lang.Object)
   */
  public boolean equals(Object object)
  {
    if (object == null)
    {
      return false;
    }
    if (object == this)
    {
      return true;
    }
    if (object instanceof ILocation)
    {
      ILocation location = this;
      ILocation otherLocation = (ILocation)object;
      do
      {
        if (!location.getName().equals(otherLocation.getName()))
        {
          return false;
        }
        location = location.getParent();
        otherLocation = otherLocation.getParent();
      }
      while (location != null && otherLocation != null);
      if (location == null)
      {
        if (otherLocation == null)
        {
          return true;
        }
        else
        {
          return false;
        }
      }
      else
      {
        if (otherLocation == null)
        {
          return false;
        }
        else
        {
          return true;
        }
      }
    }
    return false;
  }

  /*
   * @see java.lang.Object#hashCode()
   */
  public int hashCode()
  {
    StringBuffer b = new StringBuffer();
    ILocation location = this;
    while (location != null)
    {
      b.insert(0, getName());
      location = location.getParent();
    }
    return b.toString().hashCode();
  }
}