@Test
public void getByIdFromSolr() throws IOException, SolrServerException {

    //根据id查询内容
    String id="8888888";
    SolrDocument solrDocument = solrClient.getById(id);
    //获取filedName
    Collection<String> fieldNames = solrDocument.getFieldNames();
    //获取file名和内容
    Map<String, Object> fieldValueMap = solrDocument.getFieldValueMap();
    List<SolrDocument> childDocuments = solrDocument.getChildDocuments();
    String results = solrDocument.toString();
    System.out.println(results);
}