Example usage for java.lang.reflect Array newInstance

Introduction

In this page you can find the example usage for java.lang.reflect Array newInstance.

Prototype

public static Object newInstance(Class<?> componentType, int... dimensions)
        throws IllegalArgumentException, NegativeArraySizeException

Source Link

Document

Creates a new array with the specified component type and dimensions.

Usage

From source file:Main.java

public static <T extends Object> T[] toArray(List<T> list) {
    if (list == null || list.isEmpty())
        return null;

    T[] array = (T[]) Array.newInstance(list.get(0).getClass(), list.size());
    for (int i = 0; i < array.length; i++)
        array[i] = list.get(i);/*from w ww  . java2s  . c  o  m*/
    return array;
}

From source file:Main.java

@SuppressWarnings("unchecked")
public static <T> T[] appendToArrayBegining(T[] array, T element, T... elements) {

    Class<?> componentType = array.getClass().getComponentType();

    Object newArray = Array.newInstance(componentType, array.length + 1 + elements.length);

    Array.set(newArray, 0, element);
    if (elements.length > 0) {
        System.arraycopy(elements, 0, newArray, 1, elements.length);
        System.arraycopy(array, 0, newArray, elements.length, array.length);
    } else {//from  w ww.j  ava  2s  . c  om
        System.arraycopy(array, 0, newArray, 1, array.length);

    }

    return (T[]) newArray;
}

From source file:Main.java

@SuppressWarnings("unchecked")
@SafeVarargs/*from w  w  w . jav a 2  s.c  o  m*/
public static <T> T[] appendToArrayEnd(T[] array, T element, T... elements) {

    Class<?> componentType = array.getClass().getComponentType();

    Object newArray = Array.newInstance(componentType, array.length + 1 + elements.length);

    System.arraycopy(array, 0, newArray, 0, array.length);
    Array.set(newArray, array.length, element);
    System.arraycopy(elements, 0, newArray, array.length + 1, elements.length);

    return (T[]) newArray;
}

From source file:Main.java

public static <M extends Object> M[] subArray(M[] array, int start, int end) {
    end = Math.min(array.length, end);
    if (start >= end)
        return null;

    M[] result = (M[]) Array.newInstance(array[0].getClass(), end - start);
    System.arraycopy(array, start, result, 0, result.length);

    return result;
}

From source file:Main.java

@Nullable
public static <T> T[] toArrayOfType(Class<T> type, @Nullable Parcelable[] original) {
    if (original == null)
        return null;
    T[] newArray = (T[]) Array.newInstance(type, original.length);
    System.arraycopy(original, 0, newArray, 0, original.length);
    return newArray;
}

From source file:Main.java

/**
 * Trims an array to a given size.//from w w w  . j av a 2 s  .  c o  m
 *
 * @param f Array to be trimmed.
 * @return Trimmed array 
 */

static public Object trimArray(Object[] list, int newSize) {
    Class type = list.getClass().getComponentType();
    Object temp = Array.newInstance(type, newSize);
    System.arraycopy(list, 0, temp, 0, newSize);
    return temp;
}

From source file:Main.java

public static <T> T[] subArray(T[] x, int start, int len) {
    if (start + len > x.length)
        throw new IllegalArgumentException("length + start > x.length");
    T[] out = null;//from   ww  w.j av  a  2  s  . co m
    try {
        out = (T[]) Array.newInstance(x.getClass().getComponentType(), len);
    } catch (Exception e) {
        e.printStackTrace();
        throw new RuntimeException(e.getMessage());
    }
    System.arraycopy(x, start, out, 0, len);
    return out;
}

From source file:Main.java

public static <T> T[] concat(T[] first, T[]... rest) {
    int totalLength = first.length;
    for (T[] arr : rest) {
        totalLength += arr.length;//from  w w  w . j a v a 2  s  . c o  m
    }

    T[] result = (T[]) Array.newInstance(first.getClass(), totalLength);
    System.arraycopy(first, 0, result, 0, first.length);
    int pos = first.length;

    for (T[] arr : rest) {
        System.arraycopy(arr, 0, result, pos, arr.length);
        pos += arr.length;
    }

    return result;
}

From source file:Main.java

public static String[] join(String[] left, String[] right) {
    if (left == null) {
        return clone(right);
    } else if (right == null) {
        return clone(left);
    }/*from w w  w.j av a  2s .c  o m*/
    String[] joined = (String[]) Array.newInstance(String.class, left.length + right.length);
    System.arraycopy(left, 0, joined, 0, left.length);
    System.arraycopy(right, 0, joined, left.length, right.length);
    return joined;
}

From source file:Main.java

public static <T> T[] joinArrays(final Class<T> type, final T[]... arrs) {
    int total = 0;
    for (final T[] arr : arrs) {
        if (arr != null)
            total += arr.length;//from  w  w w .ja  va  2s .c om
    }
    final T[] ret = (T[]) Array.newInstance(type, total);
    int x = 0;
    for (final T[] arr : arrs) {
        if (arr != null) {
            System.arraycopy(arr, 0, ret, x, arr.length);
            x += arr.length;
        }
    }
    return ret;
}