org.powertac.util.ListTools Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of common Show documentation

Domain types, services, utilities shared by Power TAC server and agents

There is a newer version: 1.9.0

/*
 * Copyright 2009-2011 the original author or authors.
 *
 * 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 org.powertac.util;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * A collection of static methods intended to simplify list processing
 * tasks. Much of the content is modeled on web resources.
 * @author John Collins
 */
public class ListTools
{
  /**
   * Filters a Collection using a Predicate, returning a List.
   */
  public static  List filter (Collection target, Predicate pred)
  {
    List result = new ArrayList();
    for (T item : target) {
      if (pred.apply(item)) {
        result.add(item);
      }
    }
    return result;
  }
  
  /**
   * Returns the first element of a Collection that satisfies a Predicate.
   */
  public static  T findFirst (Collection target, Predicate pred)
  {
    for (T item : target) {
      if (pred.apply(item)) {
        return item;
      }
    }
    return null;
  }
}