private SolrServer createEmbeddedSolrServer(String core) throws Exception {
   System.setProperty("solr.solr.home", core);
   CoreContainer.Initializer initializer = new CoreContainer.Initializer();
   CoreContainer coreContainer = initializer.initialize();
   return new EmbeddedSolrServer(coreContainer, "");
 }
  public static void validate(File solrCoreDir, String dataDirPropertyName, Fields schemeFields)
      throws IOException {

    // Verify solrHomeDir exists
    if (!solrCoreDir.exists() || !solrCoreDir.isDirectory()) {
      throw new TapException("Solr core directory doesn't exist: " + solrCoreDir);
    }

    File tmpSolrHome = makeTempSolrHome(solrCoreDir);

    // Set up a temp location for Solr home, where we're write out a synthetic solr.xml
    // that references the core directory.
    String coreName = solrCoreDir.getName();
    String corePath = solrCoreDir.getAbsolutePath();
    String solrXmlContent =
        String.format(
            "<solr><cores><core name=\"%s\" instanceDir=\"%s\"></core></cores></solr>",
            coreName, corePath);
    File solrXmlFile = new File(tmpSolrHome, "solr.xml");
    FileUtils.write(solrXmlFile, solrXmlContent);

    // Set up a temp location for data, so when we instantiate the coreContainer,
    // we don't pollute the solr home with a /data sub-dir.
    String tmpFolder = System.getProperty("java.io.tmpdir");
    File tmpDataDir = new File(tmpFolder, UUID.randomUUID().toString());
    tmpDataDir.mkdir();

    System.setProperty("solr.solr.home", tmpSolrHome.getAbsolutePath());
    System.setProperty(dataDirPropertyName, tmpDataDir.getAbsolutePath());
    System.setProperty(
        "enable.special-handlers", "false"); // All we need is the update request handler
    System.setProperty(
        "enable.cache-warming", "false"); // We certainly don't need to warm the cache

    CoreContainer.Initializer initializer = new CoreContainer.Initializer();
    CoreContainer coreContainer = null;

    try {
      coreContainer = initializer.initialize();
      Collection<SolrCore> cores = coreContainer.getCores();
      SolrCore core = null;

      if (cores.size() == 0) {
        throw new TapException("No Solr cores are available");
      } else if (cores.size() > 1) {
        throw new TapException("Only one Solr core is supported");
      } else {
        core = cores.iterator().next();
      }

      IndexSchema schema = core.getSchema();
      Map<String, SchemaField> solrFields = schema.getFields();
      Set<String> schemeFieldnames = new HashSet<String>();

      for (int i = 0; i < schemeFields.size(); i++) {
        String fieldName = schemeFields.get(i).toString();
        if (!solrFields.containsKey(fieldName)) {
          throw new TapException("Sink field name doesn't exist in Solr schema: " + fieldName);
        }

        schemeFieldnames.add(fieldName);
      }

      for (String solrFieldname : solrFields.keySet()) {
        SchemaField solrField = solrFields.get(solrFieldname);
        if (solrField.isRequired() && !schemeFieldnames.contains(solrFieldname)) {
          throw new TapException("No sink field name for required Solr field: " + solrFieldname);
        }
      }
    } finally {
      if (coreContainer != null) {
        coreContainer.shutdown();
      }
    }
  }