com.orientechnologies.common.util.OCollections Maven / Gradle / Ivy
/*
*
* * Copyright 2010-2016 OrientDB LTD (http://orientdb.com)
* *
* * 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.
* *
* * For more information: http://orientdb.com
*
*/
package com.orientechnologies.common.util;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
/** Set of utility methods to work with collections. */
public class OCollections {
/**
* This method is used to find item in collection using passed in comparator. Only 0 value
* (requested object is found) returned by comparator is taken into account the rest is ignored.
*
* @param list List in which value should be found.
* @param object Object to find.
* @param comparator Comparator is sued for search.
* @param Type of collection elements.
* @return Index of found item or -1 otherwise.
*/
public static int indexOf(
final List list, final T object, final Comparator comparator) {
int i = 0;
for (final T item : list) {
if (comparator.compare(item, object) == 0) return i;
i++;
}
return -1;
}
/**
* This method is used to find an item in an array.
*
* @param array Array in which value should be found.
* @param object Object to find.
* @return Index of found item or -1 otherwise.
*/
public static int indexOf(final Object[] array, final Comparable object) {
for (int i = 0; i < array.length; ++i) {
if (object.compareTo(array[i]) == 0)
// FOUND
return i;
}
return -1;
}
/**
* This method is used to find a number in an array.
*
* @param array Array of integers in which value should be found.
* @param object number to find.
* @return Index of found item or -1 otherwise.
*/
public static int indexOf(final int[] array, final int object) {
for (int i = 0; i < array.length; ++i) {
if (array[i] == object)
// FOUND
return i;
}
return -1;
}
/**
* Create a string representation of all objects in the given Iterable. example :
* [value1,value2,value3]
*
* @param iterable
* @return String
*/
public static String toString(Iterable iterable) {
final StringBuilder builder = new StringBuilder(512);
builder.append('[');
int cnt = 0;
final Iterator ite = iterable.iterator();
while (ite.hasNext()) {
if (cnt != 0) {
builder.append(',');
}
cnt++;
final Object obj = ite.next();
builder.append(obj);
}
builder.append(']');
return builder.toString();
}
}