Class Metaphone

All Implemented Interfaces:
Encoder, StringEncoder

public class Metaphone extends Object implements StringEncoder
Encodes a string into a Metaphone value.

Initial Java implementation by William B. Brogden. December, 1997. Permission given by wbrogden for code to be used anywhere.

Hanging on the Metaphone by Lawrence Philips in Computer Language of Dec. 1990, p 39.

Note, that this does not match the algorithm that ships with PHP, or the algorithm found in the Perl implementations:

They have had undocumented changes from the originally published algorithm. For more information, see CODEC-57.

This class is conditionally thread-safe. The instance field for maximum code length is mutable setMaxCodeLen(int) but is not volatile, and accesses are not synchronized. If an instance of the class is shared between threads, the caller needs to ensure that suitable synchronization is used to ensure safe publication of the value between threads, and must not invoke setMaxCodeLen(int) after initial setup.

  • Constructor Details

  • Method Details

    • encode

      public Object encode(Object obj) throws EncoderException
      Encodes an Object using the metaphone algorithm. This method is provided in order to satisfy the requirements of the Encoder interface, and will throw an EncoderException if the supplied object is not of type String.
      Specified by:
      encode in interface Encoder
      obj - Object to encode
      An object (or type String) containing the metaphone code which corresponds to the String supplied.
      EncoderException - if the parameter supplied is not of type String
    • encode

      public String encode(String str)
      Encodes a String using the Metaphone algorithm.
      Specified by:
      encode in interface StringEncoder
      str - String object to encode
      The metaphone code corresponding to the String supplied
    • getMaxCodeLen

      public int getMaxCodeLen()
      Returns the maxCodeLen.
    • isMetaphoneEqual

      public boolean isMetaphoneEqual(String str1, String str2)
      Tests is the metaphones of two strings are identical.
      str1 - First of two strings to compare
      str2 - Second of two strings to compare
      true if the metaphones of these strings are identical, false otherwise.
    • metaphone

      public String metaphone(String txt)
      Find the metaphone value of a String. This is similar to the soundex algorithm, but better at finding similar sounding words. All input is converted to upper case. Limitations: Input format is expected to be a single ASCII word with only characters in the A - Z range, no punctuation or numbers.
      txt - String to find the metaphone code for
      A metaphone code corresponding to the String supplied
    • setMaxCodeLen

      public void setMaxCodeLen(int maxCodeLen)
      Sets the maxCodeLen.
      maxCodeLen - The maxCodeLen to set