/**
    * Copyright By Grandsoft Company Limited.  
    * 2012-6-19 上午09:36:46
    */
   package gboat2.base.plugin.struts.velocity;
   
   import java.io.File;
   import java.io.FileInputStream;
   import java.io.FileNotFoundException;
  import java.io.InputStream;
  
  import org.apache.commons.lang3.StringUtils;
  import org.apache.velocity.exception.ResourceNotFoundException;
  import org.apache.velocity.runtime.resource.loader.ClasspathResourceLoader;
  
  import com.opensymphony.xwork2.ActionContext;
  
  /**
   * 扩展 Velocity 自身的 ClasspathResourceLoader，实现 OSGI Bundle 的 vm 页面动态部署
   * @date 2013-01-14
   * @author tanxw
   * @since 1.0
   */
  public class DebugVelocityResourceLoader extends ClasspathResourceLoader {
  	
  	public static final String CURRENT_BUNDLE_RES_LOCATION = "_curr_bundle_res_location_";
  	
  	@Override
      public InputStream getResourceStream(String name)
              throws ResourceNotFoundException {
          String currBundleResPath = (String) ActionContext.getContext().get(CURRENT_BUNDLE_RES_LOCATION);
          if (StringUtils.isEmpty(currBundleResPath)) {
              return null;
          }
  
          String path = null;
          if (currBundleResPath.endsWith("/") && name.startsWith("/")) {
              path = currBundleResPath + name.substring(1);
          } else if (!currBundleResPath.endsWith("/") && !name.startsWith("/")) {
              path = currBundleResPath + "/" + name;
          } else {
              path = currBundleResPath + name;
          }
  
          File file = new File(path);
          if (file.exists()) {
              try {
                  return new FileInputStream(file);
              } catch (FileNotFoundException e) {
                  throw new ResourceNotFoundException(e);
              }
          }
  
          return null;
      }
  }