org.eclipse.jetty.util.ArrayUtil Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995-2018 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.util;
import java.io.Serializable;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
/* ------------------------------------------------------------ */
/**
*/
public class ArrayUtil
implements Cloneable, Serializable
{
/* ------------------------------------------------------------ */
public static T[] removeFromArray(T[] array, Object item)
{
if (item==null || array==null)
return array;
for (int i=array.length;i-->0;)
{
if (item.equals(array[i]))
{
Class c = array==null?item.getClass():array.getClass().getComponentType();
@SuppressWarnings("unchecked")
T[] na = (T[])Array.newInstance(c, Array.getLength(array)-1);
if (i>0)
System.arraycopy(array, 0, na, 0, i);
if (i+1 T[] addToArray(T[] array, T item, Class type)
{
if (array==null)
{
if (type==null && item!=null)
type= item.getClass();
@SuppressWarnings("unchecked")
T[] na = (T[])Array.newInstance(type, 1);
na[0]=item;
return na;
}
else
{
T[] na = Arrays.copyOf(array,array.length+1);
na[array.length]=item;
return na;
}
}
/* ------------------------------------------------------------ */
/** Add element to the start of an array
* @param array The array to add to (or null)
* @param item The item to add
* @param type The type of the array (in case of null array)
* @return new array with contents of array plus item
*/
public static T[] prependToArray(T item, T[] array, Class type)
{
if (array==null)
{
if (type==null && item!=null)
type= item.getClass();
@SuppressWarnings("unchecked")
T[] na = (T[])Array.newInstance(type, 1);
na[0]=item;
return na;
}
else
{
Class c = array.getClass().getComponentType();
@SuppressWarnings("unchecked")
T[] na = (T[])Array.newInstance(c, Array.getLength(array)+1);
System.arraycopy(array, 0, na, 1, array.length);
na[0]=item;
return na;
}
}
/* ------------------------------------------------------------ */
/**
* @param array Any array of object
* @return A new modifiable list initialised with the elements from array
.
*/
public static List asMutableList(E[] array)
{
if (array==null || array.length==0)
return new ArrayList();
return new ArrayList(Arrays.asList(array));
}
/* ------------------------------------------------------------ */
public static T[] removeNulls(T[] array)
{
for (T t : array)
{
if (t==null)
{
List list = new ArrayList<>();
for (T t2:array)
if (t2!=null)
list.add(t2);
return list.toArray(Arrays.copyOf(array,list.size()));
}
}
return array;
}
}