ColognePhonetic (Apache Commons Codec 1.9 API)

java.lang.Object
- org.apache.commons.codec.language.ColognePhonetic

All Implemented Interfaces:: Encoder, StringEncoder

public class ColognePhonetic
extends Object
implements StringEncoder

Encodes a string into a Cologne Phonetic value.

Implements the Kölner Phonetik (Cologne Phonetic) algorithm issued by Hans Joachim Postel in 1969.

The Kölner Phonetik is a phonetic algorithm which is optimized for the German language. It is related to the well-known soundex algorithm.

Algorithm

Step 1:

After preprocessing (conversion to upper case, transcription of germanic umlauts, removal of non alphabetical characters) the letters of the supplied text are replaced by their phonetic code according to the following table.

Letter	Context	Code
A, E, I, J, O, U, Y		0
H		-
B		1
P	not before H	1
D, T	not before C, S, Z	2
F, V, W		3
P	before H	3
G, K, Q		4
C	at onset before A, H, K, L, O, Q, R, U, X
C	before A, H, K, O, Q, U, X except after S, Z
X	not after C, K, Q	48
L		5
M, N		6
R		7
S, Z		8
C	after S, Z
	at onset except before A, H, K, L, O, Q, R, U, X
	not before A, H, K, O, Q, U, X
D, T	before C, S, Z
X	after C, K, Q

(Source: Wikipedia (de): Kölner Phonetik -- Buchstabencodes)

Example:

"Müller-Lüdenscheidt" => "MULLERLUDENSCHEIDT" => "6005507500206880022"

Step 2:
Collapse of all multiple consecutive code digits.
Example:
"6005507500206880022" => "6050750206802"
Step 3:
Removal of all codes "0" except at the beginning. This means that two or more identical consecutive digits can occur if they occur after removing the "0" digits.
Example:
"6050750206802" => "65752682"

This class is thread-safe.

Since:: 1.5
See Also:: Wikipedia (de): Kölner Phonetik (in German)

Constructor Summary

Constructors
Constructor and Description

ColognePhonetic()

Constructors
Constructor and Description
`ColognePhonetic()`

Method Summary

Methods
Modifier and Type	Method and Description
`String`	`colognePhonetic(String text)` Implements the Kölner Phonetik algorithm.
`Object`	`encode(Object object)` Encodes an "Object" and returns the encoded content as an Object.
`String`	`encode(String text)` Encodes a String and returns a String.
`boolean`	`isEncodeEqual(String text1, String text2)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ColognePhonetic
```
public ColognePhonetic()
```
- Method Detail
  - colognePhonetic
```
public String colognePhonetic(String text)
```
    Implements the Kölner Phonetik algorithm.
    
    In contrast to the initial description of the algorithm, this implementation does the encoding in one pass.
    
    Parameters:
    text -
    
    Returns:
    the corresponding encoding according to the Kölner Phonetik algorithm
  - encode
```
public Object encode(Object object)
              throws EncoderException
```
    Description copied from interface: Encoder
    
    Encodes an "Object" and returns the encoded content as an Object. The Objects here may just be byte[] or Strings depending on the implementation used.
    
    Specified by:
    
    encode in interface Encoder
    
    Parameters:
    object - An object to encode
    
    Returns:
    An "encoded" Object
    
    Throws:
    
    EncoderException - An encoder exception is thrown if the encoder experiences a failure condition during the encoding process.
  - encode
```
public String encode(String text)
```
    Description copied from interface: StringEncoder
    
    Encodes a String and returns a String.
    
    Specified by:
    
    encode in interface StringEncoder
    
    Parameters:
    text - the String to encode
    
    Returns:
    the encoded String
  - isEncodeEqual
```
public boolean isEncodeEqual(String text1,
                    String text2)
```

Class ColognePhonetic

Algorithm

Step 1:

Example:

Step 2:

Example:

Step 3:

Example:

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ColognePhonetic

Method Detail

colognePhonetic

encode

encode

isEncodeEqual