16.33. Value Factory Interface

public interface ValueFactory<T> {

    /**
     * Get the PropertyType of values created by this factory.
     * @return the value type; never null
     */
    PropertyType getPropertyType();

		/*
		 * Methods to create a value by converting from another value type.
		 * If the supplied value is the same type as returned by this factory,
		 * these methods return the supplied value.
		 * All of these methods throw a ValueFormatException if the supplied value
		 * could not be converted to this type.
		 */
    T create( String value ) throws ValueFormatException;
    T create( String value, TextDecoder decoder ) throws ValueFormatException;
    T create( int value ) throws ValueFormatException;
    T create( long value ) throws ValueFormatException;
    T create( boolean value ) throws ValueFormatException;
    T create( float value ) throws ValueFormatException;
    T create( double value ) throws ValueFormatException;
    T create( BigDecimal value ) throws ValueFormatException;
    T create( Calendar value ) throws ValueFormatException;
    T create( Date value ) throws ValueFormatException; 
    T create( DateTime value ) throws ValueFormatException;
    T create( Name value ) throws ValueFormatException;
    T create( Path value ) throws ValueFormatException;
    T create( Reference value ) throws ValueFormatException;
    T create( URI value ) throws ValueFormatException;
    T create( UUID value ) throws ValueFormatException;
    T create( byte[] value ) throws ValueFormatException;
    T create( Binary value ) throws ValueFormatException, IoException;
    T create( InputStream stream, long approximateLength ) throws ValueFormatException, IoException;
    T create( Reader reader, long approximateLength ) throws ValueFormatException, IoException;
    T create( Object value ) throws ValueFormatException, IoException;

    /*
     * Methods to create an array of values by converting from another array of values.
     * If the supplied values are the same type as returned by this factory,
     * these methods return the supplied array.
     * All of these methods throw a ValueFormatException if the supplied values
     * could not be converted to this type.
		 */
    T[] create( String[] values ) throws ValueFormatException;
    T[] create( String[] values, TextDecoder decoder ) throws ValueFormatException;
    T[] create( int[] values ) throws ValueFormatException;
    T[] create( long[] values ) throws ValueFormatException;
    T[] create( boolean[] values ) throws ValueFormatException;
    T[] create( float[] values ) throws ValueFormatException;
    T[] create( double[] values ) throws ValueFormatException;
    T[] create( BigDecimal[] values ) throws ValueFormatException;
    T[] create( Calendar[] values ) throws ValueFormatException;
    T[] create( Date[] values ) throws ValueFormatException;
    T[] create( DateTime[] values ) throws ValueFormatException;
    T[] create( Name[] values ) throws ValueFormatException;
    T[] create( Path[] values ) throws ValueFormatException;
    T[] create( Reference[] values ) throws ValueFormatException; 
    T[] create( URI[] values ) throws ValueFormatException;
    T[] create( UUID[] values ) throws ValueFormatException;
    T[] create( byte[][] values ) throws ValueFormatException;
    T[] create( Binary[] values ) throws ValueFormatException, IoException;
    T[] create( Object[] values ) throws ValueFormatException, IoException;

    /**
     * Create an iterator over the values (of an unknown type). The factory converts any 
     * values as required.  This is useful when wanting to iterate over the values of a property,
     * where the resulting iterator exposes the desired type.
     * @param values the values
     * @return the iterator of type T over the values, or null if the supplied parameter is null
     * @throws ValueFormatException if the conversion from an iterator of objects could not be performed
     * @throws IoException If an unexpected problem occurs during the conversion.
     */
    Iterator<T> create( Iterator<?> values ) throws ValueFormatException, IoException;
    Iterable<T> create(Iterable<?> valueIterable ) throws ValueFormatException, IoException;
}

ValueFactory<String> stringFactory = ...
Property property = ...
String value = stringFactory.create( property.getFirstValue() );

ValueFactory<String> stringFactory = ...
Property property = ...
for ( String value : stringFactory.create(property) ) {
    // do something with the values
}

ValueFactory<String> stringFactory = context.getValueFactories().getStringFactory();
Property property = ...
String value = stringFactory.create( property.getFirstValue() );

ValueFactory<String> stringFactory = context.getValueFactories().getStringFactory();
Property property = ...
for ( String value : stringFactory.create(property) ) {
    // do something with the values
}