Package com.ibm.icu.impl

Class IntTrie

  • public class IntTrie
extends Trie
    Trie implementation which stores data in int, 32 bits. 2015-sep-03: Used only in CharsetSelector which could be switched to Trie2_32 as long as that does not load ICU4C selector data.
    Since:
    release 2.1, Jan 01 2002
    See Also:
    Trie

    • Constructor Detail

      • IntTrie

        public IntTrie​(ByteBuffer bytes,
               Trie.DataManipulate dataManipulate)
        throws IOException

        Creates a new Trie with the settings for the trie data.

        Unserialize the 32-bit-aligned input stream and use the data for the trie.

        Parameters:
        bytes - file buffer to a ICU data file, containing the trie
        dataManipulate - object which provides methods to parse the char data
        Throws:
        IOException - thrown when data reading fails

      • IntTrie

        public IntTrie​(int initialValue,
               int leadUnitValue,
               Trie.DataManipulate dataManipulate)
        Make a dummy IntTrie. A dummy trie is an empty runtime trie, used when a real data trie cannot be loaded. The trie always returns the initialValue, or the leadUnitValue for lead surrogate code points. The Latin-1 part is always set up to be linear.
        Parameters:
        initialValue - the initial value that is set for all code points
        leadUnitValue - the value for lead surrogate code _units_ that do not have associated supplementary data
        dataManipulate - object which provides methods to parse the char data

    • Method Detail

      • getCodePointValue

        public final int getCodePointValue​(int ch)
        Gets the value associated with the codepoint. If no value is associated with the codepoint, a default value will be returned.
        Parameters:
        ch - codepoint
        Returns:
        offset to data

      • getLeadValue

        public final int getLeadValue​(char ch)
        Gets the value to the data which this lead surrogate character points to. Returned data may contain folding offset information for the next trailing surrogate character. This method does not guarantee correct results for trail surrogates.
        Parameters:
        ch - lead surrogate character
        Returns:
        data value

      • getBMPValue

        public final int getBMPValue​(char ch)
        Get the value associated with the BMP code point. Lead surrogate code points are treated as normal code points, with unfolded values that may differ from getLeadValue() results.
        Parameters:
        ch - the input BMP code point
        Returns:
        trie data value associated with the BMP codepoint

      • getSurrogateValue

        public final int getSurrogateValue​(char lead,
                                   char trail)
        Get the value associated with a pair of surrogates.
        Parameters:
        lead - a lead surrogate
        trail - a trail surrogate

      • getTrailValue

        public final int getTrailValue​(int leadvalue,
                               char trail)
        Get a value from a folding offset (from the value of a lead surrogate) and a trail surrogate.
        Parameters:
        leadvalue - the value of a lead surrogate that contains the folding offset
        trail - surrogate
        Returns:
        trie data value associated with the trail character

      • getLatin1LinearValue

        public final int getLatin1LinearValue​(char ch)

        Gets the latin 1 fast path value.

        Note this only works if latin 1 characters have their own linear array.

        Parameters:
        ch - latin 1 characters
        Returns:
        value associated with latin character

      • equals

        public boolean equals​(Object other)
        Checks if the argument Trie has the same data as this Trie
        Overrides:
        equals in class Trie
        Parameters:
        other - Trie to check
        Returns:
        true if the argument Trie has the same data as this Trie, false otherwise
        See Also:
        Object.hashCode()

      • hashCode

        public int hashCode()
        Description copied from class: Object
        Returns an integer hash code for this object. By contract, any two objects for which Object.equals(java.lang.Object) returns true must return the same hash code value. This means that subclasses of Object usually override both methods or neither method.

        Note that hash values must not change over time unless information used in equals comparisons also changes.

        See Writing a correct hashCode method if you intend implementing your own hashCode method.

        Overrides:
        hashCode in class Trie
        Returns:
        this object's hash code.
        See Also:
        Object.equals(java.lang.Object)

      • unserialize

        protected final void unserialize​(ByteBuffer bytes)

        Parses the input stream and stores its trie content into a index and data array

        Overrides:
        unserialize in class Trie
        Parameters:
        bytes - data buffer containing trie data

      • getSurrogateOffset

        protected final int getSurrogateOffset​(char lead,
                                       char trail)
        Gets the offset to the data which the surrogate pair points to.
        Specified by:
        getSurrogateOffset in class Trie
        Parameters:
        lead - lead surrogate
        trail - trailing surrogate
        Returns:
        offset to data

      • getValue

        protected final int getValue​(int index)
        Gets the value at the argument index. For use internally in TrieIterator
        Specified by:
        getValue in class Trie
        Parameters:
        index - value at index will be retrieved
        Returns:
        32 bit value
        See Also:
        TrieIterator

      • getInitialValue

        protected final int getInitialValue()
        Gets the default initial value
        Specified by:
        getInitialValue in class Trie
        Returns:
        32 bit value