code: public String getContent(int start, int end) throws IOException
  	{
  		// bug, 混合回车符号也许定位不到准确行数？
  		String lineSeparator = System.getProperty("line.separator");
  		Reader br  = null;
  		try {
  			br = openReader();
  			BufferedReader reader = new BufferedReader(br);
  			String line = null;
  			StringBuilder sb = new StringBuilder();
  			int index = 0;
  			while((line=reader.readLine())!=null){
  				index++;
  				if(index>=start&&index<=end){
  					sb.append(line).append(lineSeparator);
  					if(index==end){
  						break;
  					}
  				}
  			}
  			return sb.toString();
  		}finally {
  			if(br!=null) {
  				br.close();
  			}
  		}
  		
  
  	
  
  	}
docs: 得到Resource指定行数的内容，用于调试，报错等显示原有模板信息,如果获取不了 返回NUll
  
  @param start
  @param end
  @return