com.ibm.icu.impl

Class IntTrieBuilder

java.lang.Object

com.ibm.icu.impl.TrieBuilder

com.ibm.icu.impl.IntTrieBuilder

public class IntTrieBuilder
extends TrieBuilder

Builder class to manipulate and generate a trie. This is useful for ICU data in primitive types. Provides a compact way to store information that is indexed by Unicode values, such as character properties, types, keyboard values, etc. This is very useful when you have a block of Unicode data that contains significant values while the rest of the Unicode data is unused in the application or when you have a lot of redundance, such as where all 21,000 Han ideographs have the same value. However, lookup is much faster than a hash table. A trie of any primitive data type serves two purposes:

• Fast access of the indexed values.
• Smaller memory footprint.

This is a direct port from the ICU4C version

Nested Class Summary

Nested classes/interfaces inherited from class com.ibm.icu.impl.TrieBuilder

TrieBuilder.DataManipulate

Field Summary

Fields

Modifier and Type	Field and Description
protected int[]	m_data_
protected int	m_initialValue_

Fields inherited from class com.ibm.icu.impl.TrieBuilder

BMP_INDEX_LENGTH_, DATA_BLOCK_LENGTH, DATA_GRANULARITY_, INDEX_SHIFT_, m_dataCapacity_, m_dataLength_, m_index_, m_indexLength_, m_isCompacted_, m_isLatin1Linear_, m_map_, MASK_, MAX_DATA_LENGTH_, MAX_INDEX_LENGTH_, OPTIONS_DATA_IS_32_BIT_, OPTIONS_INDEX_SHIFT_, OPTIONS_LATIN1_IS_LINEAR_, SHIFT_, SURROGATE_BLOCK_COUNT_

Constructor Summary

Constructors

Constructor and Description
IntTrieBuilder(int[] aliasdata, int maxdatalength, int initialvalue, int leadunitvalue, boolean latin1linear) Constructs a build table
IntTrieBuilder(IntTrieBuilder table) Copy constructor

Method Summary

Modifier and Type	Method and Description
int	getValue(int ch) Gets a 32 bit data from the table data
int	getValue(int ch, boolean[] inBlockZero) Get a 32 bit data from the table data
int	serialize(OutputStream os, boolean reduceTo16Bits, TrieBuilder.DataManipulate datamanipulate) Serializes the build table to an output stream.
IntTrie	serialize(TrieBuilder.DataManipulate datamanipulate, Trie.DataManipulate triedatamanipulate) Serializes the build table with 32 bit data
boolean	setRange(int start, int limit, int value, boolean overwrite) Set a value in a range of code points [start..limit].
boolean	setValue(int ch, int value) Sets a 32 bit data in the table data

Methods inherited from class com.ibm.icu.impl.TrieBuilder

equal_int, findSameIndexBlock, findUnusedBlocks, isInZeroBlock

Methods inherited from class java.lang.Object

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

Field Detail

m_data_

protected int[] m_data_

m_initialValue_

protected int m_initialValue_

Constructor Detail

IntTrieBuilder

public IntTrieBuilder(IntTrieBuilder table)

Copy constructor

IntTrieBuilder

public IntTrieBuilder(int[] aliasdata,
                      int maxdatalength,
                      int initialvalue,
                      int leadunitvalue,
                      boolean latin1linear)

Constructs a build table

Parameters:

aliasdata - data to be filled into table

maxdatalength - maximum data length allowed in table

initialvalue - inital data value

latin1linear - is latin 1 to be linear

Method Detail

getValue

public int getValue(int ch)

Gets a 32 bit data from the table data

Parameters:

ch - codepoint which data is to be retrieved

Returns:

the 32 bit data

getValue

public int getValue(int ch,
                    boolean[] inBlockZero)

Get a 32 bit data from the table data

Parameters:

ch - code point for which data is to be retrieved.

inBlockZero - Output parameter, inBlockZero[0] returns true if the char maps into block zero, otherwise false.

Returns:

the 32 bit data value.

setValue

public boolean setValue(int ch,
                        int value)

Sets a 32 bit data in the table data

Parameters:

ch - codepoint which data is to be set

value - to set

Returns:

true if the set is successful, otherwise if the table has been compacted return false

serialize

public IntTrie serialize(TrieBuilder.DataManipulate datamanipulate,
                         Trie.DataManipulate triedatamanipulate)

Serializes the build table with 32 bit data

Parameters:

datamanipulate - builder raw fold method implementation

triedatamanipulate - result trie fold method

Returns:

a new trie

serialize

public int serialize(OutputStream os,
                     boolean reduceTo16Bits,
                     TrieBuilder.DataManipulate datamanipulate)
              throws IOException

Serializes the build table to an output stream. Compacts the build-time trie after all values are set, and then writes the serialized form onto an output stream. After this, this build-time Trie can only be serialized again and/or closed; no further values can be added. This function is the rough equivalent of utrie_seriaize() in ICU4C.

Parameters:

os - the output stream to which the seriaized trie will be written. If nul, the function still returns the size of the serialized Trie.

reduceTo16Bits - If true, reduce the data size to 16 bits. The resulting serialized form can then be used to create a CharTrie.

datamanipulate - builder raw fold method implementation

Returns:

the number of bytes written to the output stream.

Throws:

IOException

setRange

public boolean setRange(int start,
                        int limit,
                        int value,
                        boolean overwrite)

Set a value in a range of code points [start..limit]. All code points c with start <= c < limit will get the value if overwrite is true or if the old value is 0.

Parameters:

start - the first code point to get the value

limit - one past the last code point to get the value

value - the value

overwrite - flag for whether old non-initial values are to be overwritten

Returns:

false if a failure occurred (illegal argument or data array overrun)