# ValueType.java

    /*
     * Copyright (c) 2009, Rickard Öberg. All Rights Reserved.
     * Copyright (c) 2013, Paul Merlin. All Rights Reserved.
     *
     * Licensed under the Apache License, Version 2.0 (the "License");
     * you may not use this file except in compliance with the License.
     * You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
     * Unless required by applicable law or agreed to in writing, software
     * distributed under the License is distributed on an "AS IS" BASIS,
     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     * See the License for the specific language governing permissions and
     * limitations under the License.
     *
     */
    package org.qi4j.api.type;

    import java.util.Collections;
    import org.qi4j.api.util.NullArgumentException;
    import org.qi4j.functional.Function;
    import org.qi4j.functional.Iterables;

    import static org.qi4j.functional.Iterables.first;

    /**
     * Base class for types of values in ValueComposites and Properties.
     */
    public class ValueType
        implements HasTypes
    {

        public static ValueType of( Class<?> type )
        {
            return new ValueType( type );
        }

        /**
         * Check if a non-null object is of any of the Primitive Value Types or an array of them.
         * <p>
         *     String, Boolean, Integer, Double, Float, Long, Byte, Short and Character and their Java primitive types
         *     counterparts are considered as Primitive Value Types.
         * </p>
         * <p>
         *     Date, BigInteger, BigDecimal and JodaTime types are not considered as Primitive Value Types.
         * </p>
         *
         * @return true if object is a primitive value or an array of primitive values
         * @throws IllegalArgumentException if object is null
         */
        public static boolean isPrimitiveValue( Object object )
        {
            NullArgumentException.validateNotNull( "object", object );
            if( object instanceof String
                || object instanceof Character
                || object instanceof Boolean
                || object instanceof Integer
                || object instanceof Double
                || object instanceof Float
                || object instanceof Long
                || object instanceof Byte
                || object instanceof Short )
            {
                return true;
            }
            if( object.getClass().isArray() )
            {
                return isArrayOfPrimitiveValues( object );
            }
            return false;
        }

        private static boolean isArrayOfPrimitiveValues( Object array )
        {
            if( array instanceof String[]
                || array instanceof char[] || array instanceof Character[]
                || array instanceof boolean[] || array instanceof Boolean[]
                || array instanceof int[] || array instanceof Integer[]
                || array instanceof double[] || array instanceof Double[]
                || array instanceof float[] || array instanceof Float[]
                || array instanceof long[] || array instanceof Long[]
                || array instanceof byte[] || array instanceof Byte[]
                || array instanceof short[] || array instanceof Short[] )
            {
                return true;
            }
            return false;
        }

        public static boolean isPrimitiveValueType( ValueType valueType )
        {
            return isPrimitiveValueType( valueType.mainType() );
        }

        /**
         * @see ValueType#isPrimitiveValue(java.lang.Object)
         */
        public static boolean isPrimitiveValueType( Class<?> type )
        {
            NullArgumentException.validateNotNull( "type", type );
            if( String.class.isAssignableFrom( type ) )
            {
                return true;
            }
            if( type.isArray() )
            {
                return isPrimitiveValueType( type.getComponentType() );
            }
            return false;
        }
        protected final Iterable<Class<?>> types;

        public ValueType( Class<?> type )
        {
            this( Collections.singleton( type ) );
        }

        @SuppressWarnings( "unchecked" )
        public ValueType( Iterable<? extends Class<?>> types )
        {
            this.types = (Iterable<Class<?>>) types;
        }

        public Class<?> mainType()
        {
            return first( types );
        }

        @Override
        public Iterable<Class<?>> types()
        {
            return types;
        }

        @Override
        public String toString()
        {
            String name = Iterables.toString(
                types,
                new Function<Class<?>, String>()
                {
                    @Override
                    public String map( Class<?> item )
                    {
                        return item.getName();
                    }
                },
                "," );
            if( name.contains( "," ) )
            {
                name = "{" + name + "}";
            }
            return name;
        }
    }