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A Speedment bundle that shades all dependencies into one jar. This is useful when deploying an application on a server.

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/*
 *
 * Copyright (c) 2006-2019, Speedment, Inc. 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 com.speedment.runtime.field.expression;

import com.speedment.runtime.compute.expression.Expression;
import com.speedment.runtime.compute.trait.ToNullable;
import com.speedment.runtime.field.ReferenceField;

/**
 * Specialized expression that takes the value of a particular Speedment field
 * and maps it to a specific type.
 *
 * @param   the entity type
 * @param        the column type mapped from
 * @param        the type mapped to
 * @param   the expression type obtained if the nullability of
 *                        this expression is handled
 * @param   functional interface type returned by {@link #getMapper()}
 *
 * @author Emil Forslund
 * @since  3.1.0
 */
public interface FieldMapper, MAPPER>
extends Expression, ToNullable {

    /**
     * The field that is being mapped.
     *
     * @return  the field
     */
    ReferenceField getField();

    /**
     * Returns the functional interface implementation that is used when doing
     * the mapping. The returned object must implement one of the following
     * interfaces:
     * 
     *     {@link com.speedment.common.function.ToByteFunction}
     *     
{@link com.speedment.common.function.ToShortFunction}
     *     
{@link java.util.function.ToIntFunction}
     *     
{@link java.util.function.ToLongFunction}
     *     
{@link java.util.function.ToDoubleFunction}
     *     
{@link com.speedment.common.function.ToFloatFunction}
     *     
{@link com.speedment.common.function.ToCharFunction}
     *     
{@link com.speedment.common.function.ToBooleanFunction}
     *     
{@link java.util.function.Function}
     * 
     * The first generic type should be the boxed type returned by the getters
     * of the {@link #getField() field}. If the mapper implements
     * {@link java.util.function.Function}, then the returning type must be
     * either {@link java.lang.String}, {@link java.lang.Enum} or
     * {@link java.math.BigDecimal}.
     *
     * @return  the mapper to use
     */
    MAPPER getMapper();

}