Пример #1
0
  /**
   * Reads the schema from a file and creates the appropriate tables in the database.
   *
   * @param catalogFile
   */
  public void loadSchema(String catalogFile) {
    String line = "";
    String baseFolder = new File(catalogFile).getParent();
    try {
      BufferedReader br = new BufferedReader(new FileReader(new File(catalogFile)));

      while ((line = br.readLine()) != null) {
        // assume line is of the format name (field type, field type, ...)
        String name = line.substring(0, line.indexOf("(")).trim();
        // System.out.println("TABLE NAME: " + name);
        String fields = line.substring(line.indexOf("(") + 1, line.indexOf(")")).trim();
        String[] els = fields.split(",");
        ArrayList<String> names = new ArrayList<String>();
        ArrayList<Type> types = new ArrayList<Type>();
        String primaryKey = "";
        for (String e : els) {
          String[] els2 = e.trim().split(" ");
          names.add(els2[0].trim());
          if (els2[1].trim().toLowerCase().equals("int")) types.add(Type.INT_TYPE);
          else if (els2[1].trim().toLowerCase().equals("string")) types.add(Type.STRING_TYPE);
          else {
            System.out.println("Unknown type " + els2[1]);
            System.exit(0);
          }
          if (els2.length == 3) {
            if (els2[2].trim().equals("pk")) primaryKey = els2[0].trim();
            else {
              System.out.println("Unknown annotation " + els2[2]);
              System.exit(0);
            }
          }
        }
        Type[] typeAr = types.toArray(new Type[0]);
        String[] namesAr = names.toArray(new String[0]);
        TupleDesc t = new TupleDesc(typeAr, namesAr);
        HeapFile tabHf = new HeapFile(new File(baseFolder + "/" + name + ".dat"), t);
        addTable(tabHf, name, primaryKey);
        System.out.println("Added table : " + name + " with schema " + t);
      }
    } catch (IOException e) {
      e.printStackTrace();
      System.exit(0);
    } catch (IndexOutOfBoundsException e) {
      System.out.println("Invalid catalog entry : " + line);
      System.exit(0);
    }
  }
Пример #2
0
 /**
  * Add a new table to the catalog. This table has tuples formatted using the specified TupleDesc
  * and its contents are stored in the specified DbFile.
  *
  * @param file the contents of the table to add; file.getId() is the identfier of this
  *     file/tupledesc param for the calls getTupleDesc and getFile
  */
 public void addTable(DbFile file) {
   addTable(file, (UUID.randomUUID()).toString());
 }
Пример #3
0
 public void addTable(DbFile file, String name) {
   addTable(file, name, "");
 }