Example usage for java.lang System arraycopy

Introduction

In this page you can find the example usage for java.lang System arraycopy.

Prototype

@HotSpotIntrinsicCandidate
public static native void arraycopy(Object src, int srcPos, Object dest, int destPos, int length);

Source Link

Document

Copies an array from the specified source array, beginning at the specified position, to the specified position of the destination array.

Usage

From source file:Main.java

public static String[] shift(String[] array, int n) {
    if (n <= 0) {
        throw new IllegalArgumentException("n must a non-negative number.");
    }//  w ww .  j  av a  2s  . com

    if (n >= array.length) {
        return new String[0];
    }

    String[] dest = new String[array.length - n];
    System.arraycopy(array, n, dest, 0, array.length - n);
    return dest;
}

From source file:Main.java

public static byte[] concatAll(byte[] first, byte[]... rest) {
    int i, lenOfReadBytes;
    int totalLength = lenOfReadBytes = i = first != null ? first.length : 0;
    for (byte[] array : rest) {
        if (array != null)
            totalLength += array.length;
    }/*from  w  w w  .j  a v  a2s .c om*/
    byte[] result = new byte[totalLength];

    if (first != null) {
        System.arraycopy(first, 0, result, 0, first.length);
    }

    int b = 0;
    for (; i < totalLength; i++) {
        if (rest == null)
            b++;
        if (i >= rest[b].length + lenOfReadBytes) {
            lenOfReadBytes += rest[b++].length;
        }
        result[i] = rest[b][i - lenOfReadBytes];
    }
    return result;
}

From source file:Main.java

public static <T extends Object> T[] addItem(T[] array, T item, int index) {
    int size = array == null ? 0 : array.length;

    if (index < 0 || index > size)
        index = size;//from   w  ww. j av  a2 s . c o m

    @SuppressWarnings("unchecked")
    T[] result = (T[]) Array.newInstance(item.getClass(), size + 1);

    if (index > 0 && array != null)
        System.arraycopy(array, 0, result, 0, index);

    result[index] = item;

    if (index < result.length - 1 && array != null)
        System.arraycopy(array, index, result, index + 1, array.length - index);

    return result;
}

From source file:Main.java

/**
 * Resizes an array of Objects to a specified size.
 *
 * @param list Array to be resized.// w  ww  .  j  a  v a 2s  .  c  o m
 * @param newSize Array size after resizing
 * @return Array of type Object with the specified size
 */
static public Object resizeArray(Object[] list, int newSize) {
    Class type = list.getClass().getComponentType();
    Object temp = Array.newInstance(type, newSize);
    System.arraycopy(list, 0, temp, 0, Math.min(Array.getLength(list), newSize));
    return temp;
}

From source file:DoubleArray.java

static int[] doubleArray(int original[]) {
    int length = original.length;
    int newArray[] = new int[length * 2];
    System.arraycopy(original, 0, newArray, 0, length);
    return newArray;
}

From source file:Main.java

public static boolean[] combine(boolean[]... arrays) {
    int totalLength = 0;
    for (boolean[] booleans : arrays) {
        totalLength += booleans.length;//from   w ww  . j a  v a2  s  . c  o m
    }
    boolean[] newArray = new boolean[totalLength];
    int pointer = 0;
    for (boolean[] booleans : arrays) {
        System.arraycopy(booleans, 0, newArray, pointer, booleans.length);
        pointer += booleans.length;
    }
    return newArray;
}

From source file:Main.java

public static byte[][] chunkArray(byte[] array, int chunkSize) {
    int numOfChunks = (int) Math.ceil((double) array.length / chunkSize);
    byte[][] output = new byte[numOfChunks][];

    for (int i = 0; i < numOfChunks; ++i) {
        int start = i * chunkSize;
        int length = Math.min(array.length - start, chunkSize);

        byte[] temp = new byte[length];
        System.arraycopy(array, start, temp, 0, length);
        output[i] = temp;//from  ww w  . j  a  v  a 2 s .  c  om
    }

    return output;
}

From source file:Main.java

public static <T> T[] concatenateArrays(T[] array1, T[] array2) {
    if (isEmpty(array1)) {
        return array2;
    }//from w ww.  j a va  2 s . c om
    if (isEmpty(array2)) {
        return array1;
    }
    T[] resArray = (T[]) java.lang.reflect.Array.newInstance(array1[0].getClass(),
            array1.length + array2.length);
    System.arraycopy(array1, 0, resArray, 0, array1.length);
    System.arraycopy(array2, 0, resArray, array1.length, array2.length);
    return resArray;
}

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 ww w.ja va2  s . c  o  m
    }
    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;
}

From source file:Main.java

public static byte[] concatenate(byte[]... bytes) {
    int length = 0;
    for (byte[] array : bytes)
        length += array.length;//from w ww. jav a 2s  . co m
    byte[] result = new byte[length];
    int offset = 0;
    for (byte[] array : bytes) {
        System.arraycopy(array, 0, result, offset, array.length);
        offset += array.length;
    }
    return result;
}