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一些常用工具类

There is a newer version: 1.2.9

package com.github.dreamroute.common.util;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
import java.util.stream.Stream;

import static java.util.Optional.ofNullable;

/**
 * 描述：{@link java.util.Optional}辅助类
 *
 * @author w.dehi.2022-05-10
 */
public class CollectionUtil {
    private CollectionUtil() {}

    public static  boolean isEmpty(Collection source) {
        return source == null || source.isEmpty();
    }

    public static  boolean isNotEmpty(Collection source) {
        return !isEmpty(source);
    }

    public static  boolean isEmpty(Map source) {
        return source == null || source.isEmpty();
    }

    public static  boolean isNotEmpty(Map source) {
        return !isEmpty(source);
    }

    public static  boolean isEmpty(T[] source) {
        return source == null || source.length == 0 || Arrays.stream(source).allMatch(Objects::isNull);
    }

    public static  boolean isNotEmpty(T[] source) {
        return !isEmpty(source);
    }

    public static  List nonNull(List source) {
        return ofNullable(source).orElseGet(ArrayList::new);
    }

    public static  Stream nonNullStream(List source) {
        return nonNull(source).stream();
    }

    public static  Set nonNull(Set source) {
        return ofNullable(source).orElseGet(HashSet::new);
    }

    public static  Stream nonNullStream(Set source) {
        return nonNull(source).stream();
    }

    @SafeVarargs
    public static  List newArrayList(T... init) {
        return new ArrayList<>(Arrays.asList(init));
    }

    public static  List newArrayList(Collection c) {
        return new ArrayList<>(c);
    }

    public static  List newArrayListWithCapacity(int capacity) {
        return new ArrayList<>(capacity);
    }

}