コード例 #1
0
  /**
   * Creates a transformed copy of this expression, applying transformation provided by Transformer
   * to all its nodes. Null transformer will result in an identical deep copy of this expression.
   *
   * <p>To force a node and its children to be pruned from the copy, Transformer should return null
   * for a given node.
   *
   * <p>There is one limitation on what Transformer is expected to do: if a node is an Expression it
   * must be transformed to null or another Expression. Any other object type would result in an
   * exception.
   *
   * @since 1.1
   */
  public Expression transform(Transformer transformer) {

    Expression copy = shallowCopy();
    int count = getOperandCount();
    for (int i = 0, j = 0; i < count; i++) {
      Object operand = getOperand(i);
      Object transformedChild = operand;

      if (operand instanceof Expression) {
        transformedChild = ((Expression) operand).transform(transformer);
      } else if (transformer != null) {
        transformedChild = transformer.transform(operand);
      }

      if (transformedChild != null) {
        Object value = (transformedChild != nullValue) ? transformedChild : null;
        copy.setOperand(j, value);
        j++;
      } else if (pruneNodeForPrunedChild(operand)) {
        // bail out early...
        return null;
      }
    }

    // all the children are processed, only now transform this copy
    return (transformer != null) ? (Expression) transformer.transform(copy) : copy;
  }
コード例 #2
0
  // WARNING: (andrus) if we ever decide to make this method protected or public, we
  // need to change the signature to avoid API dependency on commons-collections
  Object runInTransaction(Transformer operation) {

    // user or container-managed or nested transaction
    if (Transaction.getThreadTransaction() != null) {
      return operation.transform(null);
    }

    // Cayenne-managed transaction

    Transaction transaction = createTransaction();
    Transaction.bindThreadTransaction(transaction);

    try {
      // implicit begin..
      Object result = operation.transform(null);
      transaction.commit();
      return result;
    } catch (Exception ex) {
      transaction.setRollbackOnly();

      // must rethrow
      if (ex instanceof CayenneRuntimeException) {
        throw (CayenneRuntimeException) ex;
      } else {
        throw new CayenneRuntimeException(ex);
      }
    } finally {
      Transaction.bindThreadTransaction(null);
      if (transaction.getStatus() == Transaction.STATUS_MARKED_ROLLEDBACK) {
        try {
          transaction.rollback();
        } catch (Exception rollbackEx) {
          // although we don't expect an exception here, print the stack, as
          // there have been some Cayenne bugs already (CAY-557) that were
          // masked by this 'catch' clause.
          jdbcEventLogger.logQueryError(rollbackEx);
        }
      }
    }
  }
コード例 #3
0
 /**
  * Evaluates the predicate returning the result of the decorated predicate once the input has been
  * transformed
  *
  * @param object the input object which will be transformed
  * @return true if decorated predicate returns true
  */
 public boolean evaluate(Object object) {
   Object result = iTransformer.transform(object);
   return iPredicate.evaluate(result);
 }