TPIE

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tpie::bbits::builder< T, O > Class Template Reference

Augmented btree builder. More...

#include <tpie/btree/base.h>

Public Member Functions

template<typename X = enab>
 builder (std::string path, comp_type comp=comp_type(), augmenter_type augmenter=augmenter_type(), enable< X,!is_internal >=enab())
 Construct a btree builder with the given storage. More...
 
template<typename X = enab>
 builder (comp_type comp=comp_type(), augmenter_type augmenter=augmenter_type(), memory_bucket_ref bucket=memory_bucket_ref(), enable< X, is_internal >=enab())
 
void push (value_type v)
 Push a value to the builder. More...
 
tree_type build (const std::string &metadata=std::string())
 Constructs and returns a btree from the value that was pushed to the builder. More...
 

Detailed Description

template<typename T, typename O>
class tpie::bbits::builder< T, O >

Augmented btree builder.

The fanout and location of nodes is decided by the store type S C is the item comparator type A is the type of the augmentation computation fuctor

Definition at line 205 of file base.h.

Constructor & Destructor Documentation

template<typename T , typename O >
template<typename X = enab>
tpie::bbits::builder< T, O >::builder ( std::string  path,
comp_type  comp = comp_type(),
augmenter_type  augmenter = augmenter_type(),
enable< X,!is_internal >  = enab() 
)
inlineexplicit

Construct a btree builder with the given storage.

Definition at line 214 of file btree_builder.h.

215  : m_state(store_type(path, true), std::move(augmenter), typename state_type::keyextract_type())
216  , m_comp(comp)
217  , m_serialized_size(0)
218  , m_size(0)
219  {}

Member Function Documentation

template<typename T , typename O >
tree_type tpie::bbits::builder< T, O >::build ( const std::string &  metadata = std::string())
inline

Constructs and returns a btree from the value that was pushed to the builder.

The btree builder should not be used again after this point.

Definition at line 256 of file btree_builder.h.

256  {
257  m_state.store().set_size(m_size);
258 
259  // finish building the tree by traversing all levels and constructing leaves/nodes
260  // construct one or two leaves if neccesary
261  if(m_items.size() > 0) {
262  if(!is_serialized && m_items.size() > S::max_leaf_size()) // construct two leaves if necessary
263  construct_leaf(m_items.size()/2);
264  construct_leaf(m_items.size()); // construct a leaf with the remaining items
265  }
266 
267  // if there already exists internal nodes and there are leaves left: construct a new internal node(since there is guaranteed to be atleast S::min_internal_size leaves)
268  // if there do not exist internal nodes, then only construct an internal node if there is more than one leaf
269  if((m_internal_nodes.size() == 0 && m_leaves.size() > 1) || (m_internal_nodes.size() > 0 && m_leaves.size() > 0)) {
270  if(m_leaves.size() > 2*S::max_internal_size() ) // construct two nodes if necessary
271  construct_internal_from_leaves(m_leaves.size()/3);
272  if(m_leaves.size() > S::max_internal_size()) // construct two nodes if necessary
273  construct_internal_from_leaves(m_leaves.size()/2);
274  construct_internal_from_leaves(m_leaves.size()); // construct a node from the remaining leaves
275  }
276 
277  for(size_t i = 0; i < m_internal_nodes.size(); ++i) {
278  // if there already exists internal nodes at a higher level and there are nodes at this level left: construct a new internal node at the higher level.
279  // if there do not exist internal nodes at a higher level, then only construct an internal nodes at that level if there are more than one node at this level.
280  if((m_internal_nodes.size() == i+1 && m_internal_nodes[i].size() > 1)
281  || (m_internal_nodes.size() > i+1 && m_internal_nodes[i].size() > 0)) {
282  if(m_internal_nodes[i].size() > 2*S::max_internal_size())
283  construct_internal_from_internal(m_internal_nodes[i].size()/3, i);
284  if(m_internal_nodes[i].size() > S::max_internal_size())
285  construct_internal_from_internal(m_internal_nodes[i].size()/2, i);
286  construct_internal_from_internal(m_internal_nodes[i].size(), i);
287  }
288  }
289 
290  // find the root and set it as such
291 
292  if(m_internal_nodes.size() == 0 && m_leaves.size() == 0) // no items were pushed
293  m_state.store().set_height(0);
294  else {
295  m_state.store().set_height(m_internal_nodes.size() + 1);
296  if(m_leaves.size() == 1)
297  m_state.store().set_root(m_leaves.front().leaf);
298  else
299  m_state.store().set_root(m_internal_nodes.back().front().internal);
300  }
301  if (metadata.size()) {
302  m_state.store().flush();
303  m_state.store().set_metadata(metadata);
304  }
305  m_state.store().finalize_build();
306  return tree_type(std::move(m_state), std::move(m_comp));
307  }
template<typename T , typename O >
void tpie::bbits::builder< T, O >::push ( value_type  v)
inline

Push a value to the builder.

Values are expected to be received in order

Parameters
vThe value to be pushed

Definition at line 235 of file btree_builder.h.

References tpie::serialized_size().

235  {
236  ++m_size;
237  if (is_serialized) {
238  size_t s = serialized_size(v);
239  if (m_items.size() == S::max_leaf_size() ||
240  (s + m_serialized_size > block_size_getter<S, is_serialized>::v() && m_serialized_size))
241  extract_nodes();
242  m_items.push_back(v);
243  m_serialized_size += s;
244  } else {
245  m_items.push_back(v);
246 
247  // try to construct nodes from items if possible
248  if(m_items.size() < leaf_tipping_point()) return;
249  extract_nodes();
250  }
251  }
size_t serialized_size(const T &v)
Given a serializable, serialize it and measure its serialized size.

The documentation for this class was generated from the following files: