Java Collection to Array toDoubleArray(Collection items)

Description

Convert a Collection of Numbers to an array of primitive doubles Null values will be skipped in the array

License

Open Source License

Parameter

Parameter	Description
items	a parameter

Declaration

public static double[] toDoubleArray(Collection<? extends Number> items) 

Method Source Code

//package com.java2s;
/***************************************************************************
 *  Copyright (C) 2011 by H-Store Project                                  *
 *  Brown University                                                       *
 *  Massachusetts Institute of Technology                                  *
 *  Yale University                                                        *
 *                                                                         *
 *  http://hstore.cs.brown.edu/                                            *
 *                                                                         *
 *  Permission is hereby granted, free of charge, to any person obtaining  *
 *  a copy of this software and associated documentation files (the        *
 *  "Software"), to deal in the Software without restriction, including    *
 *  without limitation the rights to use, copy, modify, merge, publish,    *
 *  distribute, sublicense, and/or sell copies of the Software, and to     *
 *  permit persons to whom the Software is furnished to do so, subject to  *
 *  the following conditions:                                              *
 *                                                                         *
 *  The above copyright notice and this permission notice shall be         *
 *  included in all copies or substantial portions of the Software.        *
 *                                                                         *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        *
 *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     *
 *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
 *  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR      *
 *  OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,  *
 *  ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR  *
 *  OTHER DEALINGS IN THE SOFTWARE.                                        *
 ***************************************************************************/

import java.util.Collection;

public class Main {
    /**//from  w  ww .  j a  va2 s .  c  o m
     * Convert a Collection of Numbers to an array of primitive doubles
     * Null values will be skipped in the array 
     * @param items
     * @return
     */
    public static double[] toDoubleArray(Collection<? extends Number> items) {
        double ret[] = new double[items.size()];
        int idx = 0;
        for (Number n : items) {
            if (n != null)
                ret[idx] = n.doubleValue();
            idx += 1;
        } // FOR
        return (ret);
    }
}

Related

1. toCharArray(Collection patterns)
2. toClassArray(Collection> collection)
3. toClassArray(Collection> collection)
4. toClassArray(final Collection collection)
5. toDouble(final Collection numbers)
6. toDoubleArray(Collection ds)
7. toDoubleArray(final Collection doubleColl)
8. toFloatArray(Collection collection)
9. toFloatArray(Collection c)