ResourceFinder.java

/**
 * $Id: ResourceFinder.java 48780 2008-05-08 15:13:37Z aaronz@vt.edu $
 * $URL: https://source.sakaiproject.org/contrib/caret/hierarchy/trunk/impl/src/java/org/sakaiproject/hierarchy/dao/ResourceFinder.java $
 * ResourceFinder.java - blog-wow - May 6, 2008 9:59:05 PM - azeckoski
 **************************************************************************
 * Copyright (c) 2008 Centre for Applied Research in Educational Technologies, University of Cambridge
 * Licensed under the Educational Community License version 1.0
 * 
 * A copy of the Educational Community License has been included in this 
 * distribution and is available at: http://www.opensource.org/licenses/ecl1.php
 *
 * Aaron Zeckoski (azeckoski@gmail.com) (aaronz@vt.edu) (aaron@caret.cam.ac.uk)
 */

package org.sakaiproject.hierarchy.dao;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;


/**
 * Allows us to find resources in our pack since the Sakai context classloader is wrong,
 * too bad it is not correct, that would be cool, but it is wrong and it is not cool<br/>
 * Takes a list of paths to resources and turns them into 
 * 
 * @author Aaron Zeckoski (aaron@caret.cam.ac.uk)
 */
public class ResourceFinder {

   private static List<Resource> makeResources(List<String> paths) {
      List<Resource> rs = new ArrayList<Resource>();
      if (paths != null && !paths.isEmpty()) {
         ClassLoader cl = ResourceFinder.class.getClassLoader();
         for (String path : paths) {
            Resource r = new ClassPathResource(path, cl);
            if (r.exists()) {
               rs.add(r);
            }
         }
      }
      return rs;
   }

   /**
    * Resolves a list of paths into resources within the current classloader
    * @param paths a list of paths to resources (org/sakaiproject/mystuff/Thing.xml)
    * @return an array of Spring Resource objects
    */
   public static Resource[] getResources(List<String> paths) {
      return makeResources(paths).toArray(new Resource[] {});
   }

   public static File[] getFiles(List<String> paths) {
      List<Resource> rs = makeResources(paths);
      File[] files = new File[rs.size()];
      for (int i = 0; i < rs.size(); i++) {
         Resource r = rs.get(i);
         try {
            files[i] = r.getFile();
         } catch (IOException e) {
            throw new RuntimeException("Failed to get file for: " + r.getFilename(), e);
         }
      }
      return files;
   }

   public static InputStream[] getInputStreams(List<String> paths) {
      List<Resource> rs = makeResources(paths);
      InputStream[] streams = new InputStream[rs.size()];
      for (int i = 0; i < rs.size(); i++) {
         Resource r = rs.get(i);
         try {
            streams[i] = r.getInputStream();
         } catch (IOException e) {
            throw new RuntimeException("Failed to get inputstream for: " + r.getFilename(), e);
         }
      }
      return streams;
   }

}