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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.common.codegen.internal.util;
import java.util.Collections;
import java.util.Set;
import java.util.StringJoiner;
import java.util.function.BiConsumer;
import java.util.function.BinaryOperator;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import static com.speedment.common.codegen.internal.util.StaticClassUtil.instanceNotAllowed;
/**
* Utility methods for collecting streams in various ways.
*
* @author Per Minborg
* @author Emil Forslund
* @since 2.1
*/
public final class CollectorUtil {
/**
* Similar to the
* {@link Collectors#joining(CharSequence, CharSequence, CharSequence)}
* method except that this method surrounds the result with the specified
* {@code prefix} and {@code suffix} even if the stream is empty.
*
* @param delimiter the delimiter to separate the strings
* @param prefix the prefix to put before the result
* @param suffix the suffix to put after the result
* @return a {@link Collector} for joining string elements
*/
public static Collector joinIfNotEmpty(String delimiter, String prefix, String suffix) {
return new CollectorImpl<>(
() -> new StringJoiner(delimiter),
StringJoiner::add,
StringJoiner::merge,
s -> s.length() > 0
? prefix + s + suffix
: s.toString(),
Collections.emptySet()
);
}
/**
* Simple implementation class for {@code Collector}.
*
* @param the type of elements to be collected
* @param the type of the intermediate holder
* @param the type of the result
*/
static class CollectorImpl implements Collector {
private final Supplier supplier;
private final BiConsumer accumulator;
private final BinaryOperator combiner;
private final Function finisher;
private final Set characteristics;
CollectorImpl(Supplier supplier,
BiConsumer accumulator,
BinaryOperator combiner,
Function finisher,
Set characteristics) {
this.supplier = supplier;
this.accumulator = accumulator;
this.combiner = combiner;
this.finisher = finisher;
this.characteristics = characteristics;
}
@SuppressWarnings("unchecked")
CollectorImpl(Supplier supplier,
BiConsumer accumulator,
BinaryOperator combiner,
Set characteristics) {
this(supplier, accumulator, combiner, i -> (R) i, characteristics);
}
@Override
public BiConsumer accumulator() {
return accumulator;
}
@Override
public Supplier supplier() {
return supplier;
}
@Override
public BinaryOperator combiner() {
return combiner;
}
@Override
public Function finisher() {
return finisher;
}
@Override
public Set characteristics() {
return characteristics;
}
}
/**
* Utility classes should not be instantiated.
*/
private CollectorUtil() {
instanceNotAllowed(getClass());
}
}