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Simple to use OpenPGP API for Java based on Bouncycastle
// SPDX-FileCopyrightText: 2021 Paul Schaub
//
// SPDX-License-Identifier: Apache-2.0
package org.pgpainless.util;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
public final class CollectionUtils {
private CollectionUtils() {
}
/**
* Return all items returned by the {@link Iterator} as a {@link List}.
*
* @param iterator iterator
* @param type
* @return list
*/
public static List iteratorToList(Iterator iterator) {
List items = new ArrayList<>();
while (iterator.hasNext()) {
I item = iterator.next();
items.add(item);
}
return items;
}
/**
* Return a new array which contains t
as first element, followed by the elements of ts
.
* @param t head
* @param ts tail
* @param type
* @return t and ts as array
*/
public static T[] concat(T t, T[] ts) {
T[] concat = (T[]) Array.newInstance(t.getClass(), ts.length + 1);
concat[0] = t;
System.arraycopy(ts, 0, concat, 1, ts.length);
return concat;
}
/**
* Return true, if the given array ts
contains the element t
.
* @param ts elements
* @param t searched element
* @param type
* @return true if ts contains t, false otherwise
*/
public static boolean contains(T[] ts, T t) {
for (T i : ts) {
if (i.equals(t)) {
return true;
}
}
return false;
}
/**
* Add all items from the iterator to the collection.
*
* @param type of item
* @param iterator iterator to gather items from
* @param collection collection to add items to
*/
public static void addAll(Iterator iterator, Collection collection) {
while (iterator.hasNext()) {
collection.add(iterator.next());
}
}
}