Class DeltaBuilder

java.lang.Object

io.crums.util.mrkl.Builder

io.crums.util.mrkl.FixedLeafBuilder

io.crums.util.mrkl.DeltaBuilder

public class DeltaBuilder
extends FixedLeafBuilder

Builds an incrementally bigger tree by only recalculating and maintaining deltas. Note this is an implementation path to building file-backed trees that would otherwise have trouble fitting in memory.

See Also:

• DeltaTree

Field Summary

Fields inherited from class io.crums.util.mrkl.Builder

copyOnWrite, data, digest, lock

Constructor Summary

Constructors

Constructor	Description
DeltaBuilder(Tree tree)	Constructs a copy-on-write instance.
DeltaBuilder(Tree tree, boolean copyOnWrite)	Creates a new instance.

Method Summary

Modifier and Type	Method	Description
int	add(byte[] item, int off, int len)	Items only the width of the (hash) digest width are allowed because this is an omni-width tree.
Tree	build()	Builds and returns the tree.
void	clear()	Clears the state of the instance, as if new.
int	itemsAdded()	Returns the total number of items added (appended).
protected DeltaTree	packageTree()

Methods inherited from class io.crums.util.mrkl.FixedLeafBuilder

leafWidth

Methods inherited from class io.crums.util.mrkl.Builder

add, completeTree, count, getHashAlgo, hash, hashWidth, item, level, levelSize, newByteArrayList

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

DeltaBuilder

public DeltaBuilder(Tree tree)

Constructs a copy-on-write instance.

Parameters:

tree - the base tree to start from

See Also:

• DeltaBuilder(Tree, boolean)

DeltaBuilder

public DeltaBuilder(Tree tree,
 boolean copyOnWrite)

Creates a new instance.

Parameters:

tree - the base tree to start from

copyOnWrite - if true, then every Builder.add(byte[]) is argument is copied (the argument's value is considered volatile). When you know you won't be modifying the input arguments set this to false

Method Details

build

public Tree build()

Description copied from class: Builder

Builds and returns the tree. On return the builder is cleared.

Overrides:

build in class FixedLeafBuilder

See Also:

• Builder.clear()

packageTree

protected DeltaTree packageTree()

Overrides:

packageTree in class FixedLeafBuilder

clear

public void clear()

Description copied from class: Builder

Clears the state of the instance, as if new.

Overrides:

clear in class Builder

add

public int add(byte[] item,
 int off,
 int len)
        throws IndexOutOfBoundsException

Items only the width of the (hash) digest width are allowed because this is an omni-width tree.

Adds the specified item as the next leaf node are returns its leaf index.

Overrides:

add in class FixedLeafBuilder

Parameters:

item - the item's data (copied)

off - starting offset into item

len - = FixedLeafBuilder.leafWidth()

Returns:

the item's leaf node index in the to-be built tree

Throws:

IndexOutOfBoundsException

itemsAdded

public int itemsAdded()

Returns the total number of items added (appended).