org.srplib.conversion.mapper

Class MatcherMapConverter<I,O>

java.lang.Object

org.srplib.conversion.mapper.MatcherMapConverter<I,O>

All Implemented Interfaces:

java.io.Serializable, org.srplib.conversion.Converter<I,O>

public class MatcherMapConverter<I,O>
extends java.lang.Object
implements org.srplib.conversion.Converter<I,O>, java.io.Serializable

Converter-mapper. Converts one value set to other value set as well as default value behavior (default value or an exception).

Useful as a replacement for switch...case...default and if...else chains.

Typical use cases:
• error code to error message translation
• object status to CSS class translation
• etc.

Internally this implementation leverages Hamcrest Matcher. First matcher wins.

Caution! If matchers are order sensitive, use LinkedHashMap implementation.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	DEFAULT_NO_MATCH_MESSAGE_PATTERN

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	MatcherMapConverter()
	MatcherMapConverter(java.util.Map<org.hamcrest.Matcher<I>,O> matcherMap) Creates converter using Matcher to object map.

Method Summary

Modifier and Type	Method and Description
O	convert(I input) Tries to find target value for specified input value.
O	getDefaultValue() Return an object to be returned if no matcher found for specified value.
protected void	put(org.hamcrest.Matcher<I> key, O value)
void	setDefaultValue(O defaultValue) Set an object to be returned if no matcher found for specified value.
void	setNoMatchMessagePattern(java.lang.String pattern) Set message pattern to be used to construct error message when no matches is found.
void	setThrowExceptionOnNoMatch(boolean throwExceptionOnNoMatch) Specifies whether to throw an exception if no match is found and no default value is specified.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_NO_MATCH_MESSAGE_PATTERN

public static final java.lang.String DEFAULT_NO_MATCH_MESSAGE_PATTERN

See Also:

Constant Field Values

Constructor Detail

MatcherMapConverter

public MatcherMapConverter(java.util.Map<org.hamcrest.Matcher<I>,O> matcherMap)

Creates converter using Matcher to object map.

Parameters:

matcherMap - Map matcher to object map (non-null). Use LinkedHashMap if matchers are ordered)

Throws:

java.lang.IllegalArgumentException - if matcherMap is null

MatcherMapConverter

protected MatcherMapConverter()

Method Detail

put

protected final void put(org.hamcrest.Matcher<I> key,
                         O value)

getDefaultValue

public O getDefaultValue()

Return an object to be returned if no matcher found for specified value.

Returns:

Object a default object

setThrowExceptionOnNoMatch

public void setThrowExceptionOnNoMatch(boolean throwExceptionOnNoMatch)

Specifies whether to throw an exception if no match is found and no default value is specified.

Parameters:

throwExceptionOnNoMatch - boolean a flag. Default value is true.

setDefaultValue

public void setDefaultValue(O defaultValue)

Set an object to be returned if no matcher found for specified value.

Parameters:

defaultValue - Object a default value. If not specified then an exception will be thrown/

setNoMatchMessagePattern

public void setNoMatchMessagePattern(java.lang.String pattern)

Set message pattern to be used to construct error message when no matches is found.

Parameters:

pattern - String message pattern with single string placeholder '%s'

convert

public O convert(I input)

Tries to find target value for specified input value.

Specified by:

convert in interface org.srplib.conversion.Converter<I,O>

Parameters:

input - input value

Returns:

output value if mapping is defined by this matcher or default value (if defined) or null depending on throwExceptionOnNoMatch value otherwise throws an exception.

Throws:

java.lang.IllegalArgumentException - if mapping isn't found and default value isn't defined and throwExceptionOnNoMatch == true.