Exemplo n.º 1
0
  public static void createIndex(String tableName, Index index) {
    Value table_ = cm.GetTableInformation(tableName);
    Value attr_;
    BPlusTree thisTree = new BPlusTree(index);

    String filename = tableName;
    try {
      mapInsert(tableName, index);
      RM_FileHandler rmf = RM_Manager.getInstance().openFile(filename);
      RM_FileScan rmfs =
          new RM_FileScan(
              rmf, Constant.TYPE.INT, 4, 0, Constant.COMP_OP.NO_OP, PF_Manager.intTobyteArray(1));
      RM_Record rmr = rmfs.getNextRec();

      while (rmr != null) {
        byte[] Record = rmr.getData();
        byte[] key = getColumnValue(tableName, index, Record);
        thisTree.insert(key, rmr.getRid().getPageNum(), rmr.getRid().getSlotNum());
        rmr = rmfs.getNextRec();
      }
    } catch (NullPointerException e) {
      e.printStackTrace();
      System.err.println("must not be null for key.");
    } catch (Exception e) {
      e.printStackTrace();
      System.err.println("the index has not been created.");
    }

    // index.rootNum=thisTree.myRootBlock.blockOffset;
    setIndexRoot(index.indexName, thisTree.myRootBlock.getPageNum());
    System.out.println("Create index successfully!");
  }
Exemplo n.º 2
0
public class IndexManager {
  private static CatalogManager cm = CatalogManager.getInstance();
  private static RM_Manager rm = RM_Manager.getInstance();
  private static TreeMap<String, Integer> mapIndexRoot = new TreeMap<String, Integer>();
  private static TreeMap<String, HashSet<Index>> mapName2Index =
      new TreeMap<String, HashSet<Index>>();
  /*	public static Buffer buf;

  IndexManager(Buffer buffer){
  	buf = buffer;
  } */
  private static IndexManager Instant = new IndexManager();

  public static IndexManager getInstance() {
    return Instant;
  }

  private static byte[] getColumnValue(String tableName, Index index, byte[] row) {
    /*		Value table_ = cm.GetTableInformation(tableName);
    Value attr_;
    int st = 0,  en = 0;
    for(int i = 0; i <= table_.getLength(); i++){
    	attr_ = cm.GetAttrInformation(tableName, i);
    	st = en;
    	en += attr_.getLength();
    }*/
    int st = 0, en = 0;
    for (int i = 0; i < index.column; i++) {
      st = en;
      en += cm.GetAttrInformation(tableName, i).getLength();
    }
    byte[] colValue = new byte[en - st];
    for (int j = 0; j < en - st; j++) {
      colValue[j] = row[st + j];
    }
    return colValue;
  }

  static boolean mapInsert(String key, Index value) {
    if (mapName2Index.containsKey(key)) {
      HashSet<Index> set = mapName2Index.get(key);
      if (set.contains(value)) return false;
      set.add(value);
    } else {
      HashSet<Index> set = new HashSet<Index>();
      set.add(value);
      mapName2Index.put(key, set);
    }
    return true;
  }

  public static void createIndex(String tableName, Index index) {
    Value table_ = cm.GetTableInformation(tableName);
    Value attr_;
    BPlusTree thisTree = new BPlusTree(index);

    String filename = tableName;
    try {
      mapInsert(tableName, index);
      RM_FileHandler rmf = RM_Manager.getInstance().openFile(filename);
      RM_FileScan rmfs =
          new RM_FileScan(
              rmf, Constant.TYPE.INT, 4, 0, Constant.COMP_OP.NO_OP, PF_Manager.intTobyteArray(1));
      RM_Record rmr = rmfs.getNextRec();

      while (rmr != null) {
        byte[] Record = rmr.getData();
        byte[] key = getColumnValue(tableName, index, Record);
        thisTree.insert(key, rmr.getRid().getPageNum(), rmr.getRid().getSlotNum());
        rmr = rmfs.getNextRec();
      }
    } catch (NullPointerException e) {
      e.printStackTrace();
      System.err.println("must not be null for key.");
    } catch (Exception e) {
      e.printStackTrace();
      System.err.println("the index has not been created.");
    }

    // index.rootNum=thisTree.myRootBlock.blockOffset;
    setIndexRoot(index.indexName, thisTree.myRootBlock.getPageNum());
    System.out.println("Create index successfully!");
  }

  public static void dropIndex(String filename) {
    filename += ".index";
    File file = new File(filename);

    try {
      if (file.exists()) {
        if (file.delete()) System.out.println("The index file has been deleted.");
      } else System.out.println("The file " + filename + " has not been found.");
    } catch (Exception e) {
      System.out.println(e.getMessage());
      System.out.println("Delete index unsuccessfully!");
    }

    // buf.setInvalid(filename);  //将buf中所有与此索引相关的缓冲块都置为无效
    System.out.println("Delete index successfully!");
  }

  public static void dropTable(String filename) {
    HashSet<Index> i = mapName2Index.get(filename);
    for (Index j : i) {
      dropIndex(j.indexName);
    }
    mapName2Index.remove(filename, i);
  }

  public static RID searchEqual(Index index, byte[] key) throws Exception {
    RID off = new RID();
    try {
      // Index inx=CatalogManager.getIndex(index.indexName);
      BPlusTree thisTree = new BPlusTree(index, index.rootNum); /*This place has bugs.*/
      off = thisTree.searchKey(key);
      return off;
    } catch (NullPointerException e) {
      System.err.println();
      return null;
    }
  }

  public static void insertKey(Index index, byte[] key, int blockOffset, int offset)
      throws Exception {
    try {
      // Index inx=CatalogManager.getIndex(index.indexName);
      BPlusTree thisTree = new BPlusTree(index, index.rootNum); /*This place has bugs.*/
      thisTree.insert(key, blockOffset, offset);
      // index.rootNum=thisTree.myRootBlock.blockOffset;
      setIndexRoot(index.indexName, thisTree.myRootBlock.getPageNum());
    } catch (NullPointerException e) {
      System.err.println();
    }
  }

  public static void deleteKey(Index index, byte[] deleteKey) throws Exception {
    try {
      // Index inx=CatalogManager.getIndex(index.indexName);
      BPlusTree thisTree = new BPlusTree(index, index.rootNum); /*This place has bugs.*/
      thisTree.delete(deleteKey);
      // index.rootNum=thisTree.myRootBlock.blockOffset;
      setIndexRoot(index.indexName, thisTree.myRootBlock.getPageNum());
    } catch (NullPointerException e) {
      System.err.println();
    }
  }

  public static void setIndexRoot(String indexName, int number) {
    ;
    if (mapIndexRoot.containsKey(indexName)) {
      mapIndexRoot.replace(indexName, number);
    } else mapIndexRoot.put(indexName, number);
  }

  // 获得索引根块在文件中的block偏移量, 如果该index不存在则返回-1
  public static int getIndexRoot(String indexName) {
    if (mapIndexRoot.containsKey(indexName)) return mapIndexRoot.get(indexName);
    else return -1;
  }
}