com.firefly.utils.lang.ArrayUtils Maven / Gradle / Ivy
package com.firefly.utils.lang;
import java.io.Serializable;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
/**
* Utility methods for Array manipulation
*/
public class ArrayUtils implements Cloneable, Serializable {
private static final long serialVersionUID = 2252854725258539040L;
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 < array.length)
System.arraycopy(array, i + 1, na, i, array.length - (i + 1));
return na;
}
}
return array;
}
/**
* Add element to 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
* @param
* the array entry type
*/
public static 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
* @param
* the array entry type
*/
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.
* @param
* the array entry type
*/
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;
}
}