Here you can find the source of arrayMoveWithin(Object[] array, int moveFrom, int moveTo, int numToMove)
| Parameter | Description |
|---|---|
| array | The array to alter |
| moveFrom | The (0 based) index of the first entry to move |
| moveTo | The (0 based) index of the positition to move to |
| numToMove | The number of entries to move |
public static void arrayMoveWithin(Object[] array, int moveFrom, int moveTo, int numToMove)
//package com.java2s; //License from project: Open Source License public class Main { /**//from w w w .j a va 2 s .c o m * Moves a number of entries in an array to another point in the array, * shifting those inbetween as required. * @param array The array to alter * @param moveFrom The (0 based) index of the first entry to move * @param moveTo The (0 based) index of the positition to move to * @param numToMove The number of entries to move */ public static void arrayMoveWithin(Object[] array, int moveFrom, int moveTo, int numToMove) { if (numToMove <= 0) { return; } if (moveFrom == moveTo) { return; } if (moveFrom < 0 || moveFrom >= array.length) { throw new IllegalArgumentException("The moveFrom must be a valid array index"); } if (moveTo < 0 || moveTo >= array.length) { throw new IllegalArgumentException("The moveTo must be a valid array index"); } if (moveFrom + numToMove > array.length) { throw new IllegalArgumentException("Asked to move more entries than the array has"); } if (moveTo + numToMove > array.length) { throw new IllegalArgumentException("Asked to move to a position that doesn't have enough space"); } // Grab the bit to move Object[] toMove = new Object[numToMove]; System.arraycopy(array, moveFrom, toMove, 0, numToMove); // Grab the bit to be shifted Object[] toShift; int shiftTo; if (moveFrom > moveTo) { // Moving to an earlier point in the array // Grab everything between the two points toShift = new Object[(moveFrom - moveTo)]; System.arraycopy(array, moveTo, toShift, 0, toShift.length); shiftTo = moveTo + numToMove; } else { // Moving to a later point in the array // Grab everything from after the toMove block, to the new point toShift = new Object[(moveTo - moveFrom)]; System.arraycopy(array, moveFrom + numToMove, toShift, 0, toShift.length); shiftTo = moveFrom; } // Copy the moved block to its new location System.arraycopy(toMove, 0, array, moveTo, toMove.length); // And copy the shifted block to the shifted location System.arraycopy(toShift, 0, array, shiftTo, toShift.length); } public static void arraycopy(byte[] src, int src_position, byte[] dst, int dst_position, int length) { if (src_position < 0) throw new IllegalArgumentException("src_position was less than 0. Actual value " + src_position); if (src_position >= src.length) throw new IllegalArgumentException( "src_position was greater than src array size. Tried to write starting at position " + src_position + " but the array length is " + src.length); if (src_position + length > src.length) throw new IllegalArgumentException( "src_position + length would overrun the src array. Expected end at " + (src_position + length) + " actual end at " + src.length); if (dst_position < 0) throw new IllegalArgumentException("dst_position was less than 0. Actual value " + dst_position); if (dst_position >= dst.length) throw new IllegalArgumentException( "dst_position was greater than dst array size. Tried to write starting at position " + dst_position + " but the array length is " + dst.length); if (dst_position + length > dst.length) throw new IllegalArgumentException( "dst_position + length would overrun the dst array. Expected end at " + (dst_position + length) + " actual end at " + dst.length); System.arraycopy(src, src_position, dst, dst_position, length); } }