Program: 168456
Project: 168456
Buggy source:
/** 
 * Drop index with the mongo default name. The name is created based on the corresponding index type.
 * @param indexMetadata the index metadata
 * @param db the db
 * @throws ExecutionException if an error exist when running the db command
 */
public static void dropIndexWithDefaultName(IndexMetadata indexMetadata,DB db) throws ExecutionException {
  if (indexMetadata.getType() == IndexType.DEFAULT) {
    DBObject indexDBObject=new BasicDBObject();
    for (    ColumnMetadata columnMeta : indexMetadata.getColumns().values()) {
      indexDBObject.put(columnMeta.getName().getName(),1);
    }
    try {
      db.getCollection(indexMetadata.getName().getTableName().getName()).dropIndex(indexDBObject);
    }
 catch (    Exception e) {
      logger.error("String_Node_Str" + indexDBObject + "String_Node_Str"+ e.getMessage());
      throw new ExecutionException(e.getMessage(),e);
    }
  }
 else   if (indexMetadata.getType() == IndexType.FULL_TEXT) {
    String defaultTextIndexName;
    StringBuffer strBuf=new StringBuffer();
    int colNumber=0;
    int columnSize=indexMetadata.getColumns().size();
    for (    ColumnMetadata columnMeta : indexMetadata.getColumns().values()) {
      strBuf.append(columnMeta.getName().getName()).append("String_Node_Str");
      if (++colNumber != columnSize) {
        strBuf.append("String_Node_Str");
      }
    }
    defaultTextIndexName=strBuf.toString();
    try {
      db.getCollection(indexMetadata.getName().getTableName().getName()).dropIndex(defaultTextIndexName);
    }
 catch (    Exception e) {
      logger.error("String_Node_Str" + defaultTextIndexName + "String_Node_Str"+ e.getMessage());
      throw new ExecutionException(e.getMessage(),e);
    }
  }
 else {
    throw new MongoValidationException("String_Node_Str" + indexMetadata.getType().toString());
  }
}

Fixed version (ground truth):
/** 
 * Drop index with the mongo default name. The name is created based on the corresponding index type.
 * @param indexMetadata the index metadata
 * @param db the db
 * @throws ExecutionException if an error exist when running the db command
 */
public static void dropIndexWithDefaultName(IndexMetadata indexMetadata,DB db) throws ExecutionException {
  if (indexMetadata.getType() == IndexType.DEFAULT) {
    DBObject indexDBObject=new BasicDBObject();
    for (    ColumnMetadata columnMeta : indexMetadata.getColumns().values()) {
      indexDBObject.put(columnMeta.getName().getName(),1);
    }
    try {
      db.getCollection(indexMetadata.getName().getTableName().getName()).dropIndex(indexDBObject);
    }
 catch (    Exception e) {
      LOGGER.error("String_Node_Str" + indexDBObject + "String_Node_Str"+ e.getMessage());
      throw new ExecutionException(e.getMessage(),e);
    }
  }
 else   if (indexMetadata.getType() == IndexType.FULL_TEXT) {
    String defaultTextIndexName;
    StringBuffer strBuf=new StringBuffer();
    int colNumber=0;
    int columnSize=indexMetadata.getColumns().size();
    for (    ColumnMetadata columnMeta : indexMetadata.getColumns().values()) {
      strBuf.append(columnMeta.getName().getName()).append("String_Node_Str");
      if (++colNumber != columnSize) {
        strBuf.append("String_Node_Str");
      }
    }
    defaultTextIndexName=strBuf.toString();
    try {
      db.getCollection(indexMetadata.getName().getTableName().getName()).dropIndex(defaultTextIndexName);
    }
 catch (    Exception e) {
      LOGGER.error("String_Node_Str" + defaultTextIndexName + "String_Node_Str"+ e.getMessage());
      throw new ExecutionException(e.getMessage(),e);
    }
  }
 else {
    throw new MongoValidationException("String_Node_Str" + indexMetadata.getType().toString());
  }
}