btreemultifieldindex.java

这个是perst-269.zip下面的SOURCECODE,和大家分享了。

                      buf.extend(dst+4);
                      if (p != null) { 
                          if (!p.isPersistent())
                          {
                              getStorage().makePersistent(p);
                          }                        
                          Bytes.pack4(buf.arr, dst, p.getOid());
                      } else { 
                          Bytes.pack4(buf.arr, dst, 0);
                      }
                      dst += 4;
                      break;
                  }
                  case ClassDescriptor.tpLong:
                    buf.extend(dst+8);
                    Bytes.pack8(buf.arr, dst, f.getLong(obj));
                    dst += 8;
                    break;
                  case ClassDescriptor.tpDate:
                  {
                      Date d = (Date)f.get(obj);
                      buf.extend(dst+8);
                      Bytes.pack8(buf.arr, dst, d == null ? -1 : d.getTime());
                      dst += 8;
                      break;
                  }
                  case ClassDescriptor.tpFloat:
                    buf.extend(dst+4);
                    Bytes.pack4(buf.arr, dst, Float.floatToIntBits(f.getFloat(obj)));
                    dst += 4;
                    break;
                  case ClassDescriptor.tpDouble:
                    buf.extend(dst+8);
                    Bytes.pack8(buf.arr, dst, Double.doubleToLongBits(f.getDouble(obj)));
                    dst += 8;
                    break;
                  case ClassDescriptor.tpString:
                  {
                      buf.extend(dst+4);
                      String str = (String)f.get(obj);
                      if (str != null) { 
                          int len = str.length();
                          Bytes.pack4(buf.arr, dst, len);
                          dst += 4;
                          buf.extend(dst + len*2);
                          for (int j = 0; j < len; j++) { 
                              Bytes.pack2(buf.arr, dst, (short)str.charAt(j));
                              dst += 2;
                          }
                      } else { 
                          Bytes.pack4(buf.arr, dst, 0);
                          dst += 4;
                      }
                      break;
                  }
                  case ClassDescriptor.tpArrayOfByte:
                  {
                      buf.extend(dst+4);
                      byte[] arr = (byte[])f.get(obj);
                      if (arr != null) { 
                          int len = arr.length;
                          Bytes.pack4(buf.arr, dst, len);
                          dst += 4;                          
                          buf.extend(dst + len);
                          System.arraycopy(arr, 0, buf.arr, dst, len);
                          dst += len;
                      } else { 
                          Bytes.pack4(buf.arr, dst, 0);
                          dst += 4;
                      }
                      break;
                  }
                  default:
                    Assert.failed("Invalid type");
                }
            }
            return new Key(buf.toArray());
        } catch (Exception x) { 
            throw new StorageError(StorageError.ACCESS_VIOLATION, x);
        }
    }
            

    private Key convertKey(Key key) { 
        if (key == null) { 
            return null;
        }
        if (key.type != ClassDescriptor.tpArrayOfObject) { 
            throw new StorageError(StorageError.INCOMPATIBLE_KEY_TYPE);
        }
        Object[] values = (Object[])key.oval;
        ByteBuffer buf = new ByteBuffer();
        int dst = 0;
        for (int i = 0; i < values.length; i++) { 
            Object v = values[i];
            switch (types[i]) {
              case ClassDescriptor.tpBoolean:
                buf.extend(dst+1);
                buf.arr[dst++] = (byte)(((Boolean)v).booleanValue() ? 1 : 0);
                break;
              case ClassDescriptor.tpByte:
                buf.extend(dst+1);
                buf.arr[dst++] = ((Number)v).byteValue();
                break;
              case ClassDescriptor.tpShort:
                buf.extend(dst+2);
                Bytes.pack2(buf.arr, dst, ((Number)v).shortValue());
                dst += 2;
                break;
              case ClassDescriptor.tpChar:
                buf.extend(dst+2);
                Bytes.pack2(buf.arr, dst, (v instanceof Number) ? ((Number)v).shortValue() : (short)((Character)v).charValue());
                dst += 2;
                break;
              case ClassDescriptor.tpInt:
                buf.extend(dst+4);
                Bytes.pack4(buf.arr, dst, ((Number)v).intValue());
                dst += 4;
                break;
              case ClassDescriptor.tpObject:
                buf.extend(dst+4);
                Bytes.pack4(buf.arr, dst, v == null ? 0 : ((IPersistent)v).getOid());
                dst += 4;
                break;
              case ClassDescriptor.tpLong:
                buf.extend(dst+8);
                Bytes.pack8(buf.arr, dst, ((Number)v).longValue());
                dst += 8;
                break;
              case ClassDescriptor.tpDate:
                buf.extend(dst+8);
                Bytes.pack8(buf.arr, dst, v == null ? -1 : ((Date)v).getTime());
                dst += 8;
                break;
              case ClassDescriptor.tpFloat:
                buf.extend(dst+4);
                Bytes.pack4(buf.arr, dst, Float.floatToIntBits(((Number)v).floatValue()));
                dst += 4;
                break;
              case ClassDescriptor.tpDouble:
                buf.extend(dst+8);
                Bytes.pack8(buf.arr, dst, Double.doubleToLongBits(((Number)v).doubleValue()));
                dst += 8;
                break;
              case ClassDescriptor.tpString:
              {
                  buf.extend(dst+4);
                  if (v != null) { 
                      String str = (String)v;
                      int len = str.length();
                      Bytes.pack4(buf.arr, dst, len);
                      dst += 4;
                      buf.extend(dst + len*2);
                      for (int j = 0; j < len; j++) { 
                          Bytes.pack2(buf.arr, dst, (short)str.charAt(j));
                          dst += 2;
                      }
                  } else { 
                      Bytes.pack4(buf.arr, dst, 0);
                      dst += 4;
                  }
                  break;
              }
              case ClassDescriptor.tpArrayOfByte:
              {
                  buf.extend(dst+4);
                  if (v != null) { 
                      byte[] arr = (byte[])v;
                      int len = arr.length;
                      Bytes.pack4(buf.arr, dst, len);
                      dst += 4;                          
                      buf.extend(dst + len);
                      System.arraycopy(arr, 0, buf.arr, dst, len);
                      dst += len;
                  } else { 
                      Bytes.pack4(buf.arr, dst, 0);
                      dst += 4;
                  }
                  break;
              }
              default:
                Assert.failed("Invalid type");
            }
        }
        return new Key(buf.toArray(), key.inclusion != 0);
    }
            

    public boolean put(IPersistent obj) {
        return super.put(extractKey(obj), obj);
    }

    public IPersistent set(IPersistent obj) {
        return super.set(extractKey(obj), obj);
    }

    public void remove(IPersistent obj) {
        super.remove(new BtreeKey(extractKey(obj), obj.getOid()));
    }

    public IPersistent remove(Key key) {
        return super.remove(convertKey(key));
    }
    
    public boolean containsObject(IPersistent obj) {
        Key key = extractKey(obj);
        if (unique) { 
            return super.get(key) != null;
        } else { 
            IPersistent[] mbrs = get(key, key);
            for (int i = 0; i < mbrs.length; i++) { 
                if (mbrs[i] == obj) { 
                    return true;
                }
            }
            return false;
        }
    }

    public boolean contains(IPersistent obj) {
        Key key = extractKey(obj);
        if (unique) { 
            return super.get(key) != null;
        } else { 
            IPersistent[] mbrs = get(key, key);
            for (int i = 0; i < mbrs.length; i++) { 
                if (mbrs[i].equals(obj)) { 
                    return true;
                }
            }
            return false;
        }
    }

    public void append(IPersistent obj) {
        throw new StorageError(StorageError.UNSUPPORTED_INDEX_TYPE);
    }

    public IPersistent[] get(Key from, Key till) {
        ArrayList list = new ArrayList();
        if (root != 0) { 
            BtreePage.find((StorageImpl)getStorage(), root, convertKey(from), convertKey(till), this, height, list);
        }
        return (IPersistent[])list.toArray((Object[])Array.newInstance(cls, list.size()));
    }

    public IPersistent[] toPersistentArray() {
        IPersistent[] arr = (IPersistent[])Array.newInstance(cls, nElems);
        if (root != 0) { 
            BtreePage.traverseForward((StorageImpl)getStorage(), root, type, height, arr, 0);
        }
        return arr;
    }

    public IPersistent get(Key key) {
        return super.get(convertKey(key));
    }

    public Iterator iterator(Key from, Key till, int order) {
        return super.iterator(convertKey(from), convertKey(till), order);
    }

    public Iterator entryIterator(Key from, Key till, int order) {
        return super.entryIterator(convertKey(from), convertKey(till), order);
    }

    public Iterator select(String predicate) { 
        Query query = new QueryImpl(getStorage());
        return query.select(cls, iterator(), predicate);
    }
}