com.speedment.runtime.compute.ToStringNullable Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of runtime-deploy Show documentation
Show all versions of runtime-deploy Show documentation
A Speedment bundle that shades all dependencies into one jar. This is
useful when deploying an application on a server.
/**
*
* 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.compute;
import com.speedment.runtime.compute.expression.Expression;
import com.speedment.runtime.compute.expression.ExpressionType;
import com.speedment.runtime.compute.internal.expression.ComposedUtil;
import com.speedment.runtime.compute.internal.expression.OrElseGetUtil;
import com.speedment.runtime.compute.internal.expression.OrElseThrowUtil;
import com.speedment.runtime.compute.internal.expression.OrElseUtil;
import com.speedment.runtime.compute.trait.HasCompare;
import com.speedment.runtime.compute.trait.HasCompose;
import com.speedment.runtime.compute.trait.HasHash;
import com.speedment.runtime.compute.trait.ToNullable;
import java.util.function.Function;
/**
* Expression that given an entity returns a {@code String} value, or
* {@code null}. This expression can be implemented using a lambda, or it can be
* a result of another operation. It has additional methods for operating on it.
*
* @param type to extract from
* @see Function
*
* @author Emil Forslund
* @since 3.1.0
*/
@FunctionalInterface
public interface ToStringNullable
extends Expression,
ToNullable>,
HasHash,
HasCompare,
HasCompose {
/**
* Returns a typed {@code ToStringNullable} using the provided
* {@code lambda}.
*
* @param type to extract from
* @param lambda to convert
* @return a typed {@code ToStringNullable} using the provided
* {@code lambda}
*
* @throws NullPointerException if the provided {@code lambda} is
* {@code null}
*/
static ToStringNullable of(Function lambda) {
if (lambda instanceof ToStringNullable) {
return (ToStringNullable) lambda;
} else {
return lambda::apply;
}
}
@Override
String apply(T object);
@Override
default ExpressionType expressionType() {
return ExpressionType.STRING_NULLABLE;
}
@Override
default ToString orThrow() throws NullPointerException {
return OrElseThrowUtil.stringOrElseThrow(this);
}
@Override
default ToString orElseGet(ToString getter) {
return OrElseGetUtil.stringOrElseGet(this, getter);
}
@Override
default ToString orElse(String value) {
return OrElseUtil.stringOrElse(this, value);
}
@Override
default long hash(T object) {
return isNull(object) ? 0 : apply(object).hashCode();
}
@Override
default int compare(T first, T second) {
if (isNull(first)) {
return isNull(second) ? 0 : 1;
} else if (isNull(second)) {
return -1;
} else {
return apply(first).compareTo(apply(second));
}
}
@Override
default ToStringNullable compose(Function before) {
@SuppressWarnings("unchecked")
final Function casted = (Function) before;
return ComposedUtil.composeToStringNullable(casted, this);
}
}