Ниже приведен пример фрагмента кода, который нуждается в помощи
Пример:
[1,2,3,4,5]
1, [1,2,3,4,5]2, [1,2] и [3,4] и [5]3, [1,2,3] и [4,5]4, [1,2,3,4] и [5]Java (из комментария):
int counter = 0;
for (int i=0; i<array.length; i++) {
if (count == chunksize) {
//do something and initialize
counter = 0;
}
counter++;
}
Вы можете использовать Arrays.copyOfRange(int[] original, int from, int to) Код может быть примерно таким:
int chunk = 2; // chunk size to divide
for(int i=0;i<original.length;i+=chunk){
System.out.println(Arrays.toString(Arrays.copyOfRange(original, i, Math.min(original.length,i+chunk))));
}
Просто наткнулся на этот пост, столкнувшись с тем же вопросом. Вот как я его решил (я использовал Arrays.copyOfRange():
public static int[][] splitArray(int[] arrayToSplit, int chunkSize){
if(chunkSize<=0){
return null; // just in case :)
}
// first we have to check if the array can be split in multiple
// arrays of equal 'chunk' size
int rest = arrayToSplit.length % chunkSize; // if rest>0 then our last array will have less elements than the others
// then we check in how many arrays we can split our input array
int chunks = arrayToSplit.length / chunkSize + (rest > 0 ? 1 : 0); // we may have to add an additional array for the 'rest'
// now we know how many arrays we need and create our result array
int[][] arrays = new int[chunks][];
// we create our resulting arrays by copying the corresponding
// part from the input array. If we have a rest (rest>0), then
// the last array will have less elements than the others. This
// needs to be handled separately, so we iterate 1 times less.
for(int i = 0; i < (rest > 0 ? chunks - 1 : chunks); i++){
// this copies 'chunk' times 'chunkSize' elements into a new array
arrays[i] = Arrays.copyOfRange(arrayToSplit, i * chunkSize, i * chunkSize + chunkSize);
}
if(rest > 0){ // only when we have a rest
// we copy the remaining elements into the last chunk
arrays[chunks - 1] = Arrays.copyOfRange(arrayToSplit, (chunks - 1) * chunkSize, (chunks - 1) * chunkSize + rest);
}
return arrays; // that it
}
chunkSize = 1
[1]
[2]
[3]
[4]
[5]
chunkSize = 2
[1, 2]
[3, 4]
[5]
chunkSize = 3
[1, 2, 3]
[4, 5]
chunkSize = 4
[1, 2, 3, 4]
[5]
chunkSize = 5
[1, 2, 3, 4, 5]
chunkSize = 6
[1, 2, 3, 4, 5]
Если вы не возражаете против импорта Google Guava и преобразования в список, есть способ разделения списков:
Следующие могут достичь желаемого результата:
List<Integer> listToBeSplit = Arrays.asList(sourceArray);
int chunkSize = 3;
Lists.partition(listToBeSplit, chunkSize);
Попробуй это,
Итерируйте его и проверьте, чтобы размер куска.
int chunkSize = userInput;
//итерация и проверка условия
char[] resultArray = Arrays.copyOfRange(inputArray, start, end);
start = start + end; // check whether the start will exceeds the length of the array
Используя чистую Java 8:
public class Chunk {
public static void main(String[] args) {
int[] input = {1,2,3,4,78,999,-1,456};
int chunkSize = 3;
int[][] chunked = chunk(input, chunkSize);
Arrays.stream(chunked)
.map(Arrays::toString)
.forEach(System.out::println);
}
public static int[][] chunk(int[] input, int chunkSize) {
return IntStream.iterate(0, i -> i + chunkSize)
.limit((long) Math.ceil((double) input.length / chunkSize))
.mapToObj(j -> Arrays.copyOfRange(input, j, j + chunkSize > input.length ? input.length : j + chunkSize))
.toArray(int[][]::new);
}
}
[1, 2, 3]
[4, 78, 999]
[-1, 456]
В общем случае вы можете использовать Arrays.copyOfRange для копирования
Это должно сделать трюк
public static List<String> split(String string, int chunk) {
Pattern pattern = Pattern.compile("(([0-9]+,){" + (chunk - 1)
+ "}[0-9]+)|[0-9]+");
Matcher matcher = pattern.matcher(string);
List<String> result = new ArrayList<String>();
while (matcher.find())
result.add("[" + matcher.group() + "]");
return result;
}
Тестовый код:
for (int chunkSize = 1; chunkSize < 6; ++chunkSize) {
System.out.println("test for chunk size: " + chunkSize);
for (String string : split("[1,2,3,4,5]", chunkSize))
System.out.format("\t%s\n", string);
}
Вывод:
test for chunk size: 1
[1]
[2]
[3]
[4]
[5]
test for chunk size: 2
[1,2]
[3,4]
[5]
test for chunk size: 3
[1,2,3]
[4]
[5]
test for chunk size: 4
[1,2,3,4]
[5]
test for chunk size: 5
[1,2,3,4,5]
public static int[][] chunkArray(int[] array, int chunkSize) {
// first we need to get number of chunks by dividing length by chunkSize.
int numOfChunks = (int)Math.ceil((double)array.length / chunkSize);
// we declare 2d array to save in the chunks
int[][] output = new int[numOfChunks][];
for(int i = 0; i < numOfChunks; i++) {
int start = i * chunkSize;
int length = Math.min(array.length - start, chunkSize);
int[] temp = new int[length];
System.arraycopy(array, start, temp, 0, length);
output[i] = temp;
}
return output;
}
public class ArrayChunk {
public static void main(String[] args) {
String[][] chunked = chunkArray("1,2,3,4,5,6,7,8,9".split(","), 2);
System.out.println("Array with chunk size 2");
Arrays.stream(chunked).forEach(strings -> System.out.println(String.join(",", strings)));
chunked = chunkArray("1,2,3,4,5,6,7,8,9".split(","), 3);
System.out.println("Array with chunk size 3");
Arrays.stream(chunked).forEach(strings -> System.out.println(String.join(",", strings)));
chunked = chunkArray("1,2,3,4,5,6,7,8,9".split(","), 4);
System.out.println("Array with chunk size 4");
Arrays.stream(chunked).forEach(strings -> System.out.println(String.join(",", strings)));
chunked = chunkArray("1,2,3,4,5,6,7,8,9".split(","), 5);
System.out.println("Array with chunk size 5");
Arrays.stream(chunked).forEach(strings -> System.out.println(String.join(",", strings)));
}
private static String[][] chunkArray(String[] array, int chunkSize) {
int chunkedSize = (int) Math.ceil((double) array.length / chunkSize); // chunked array size
String[][] chunked = new String[chunkedSize][chunkSize];
for (int index = 0; index < chunkedSize; index++) {
String[] chunk = new String[chunkSize]; // small array
System.arraycopy(array, index * chunkSize, chunk, 0, Math.min(chunkSize, array.length - index * chunkSize));
chunked[index] = chunk;
}
return chunked;
}
}
Выход
Array with chunk size 2
1,2
3,4
5,6
7,8
9,null
Array with chunk size 3
1,2,3
4,5,6
7,8,9
Array with chunk size 4
1,2,3,4
5,6,7,8
9,null,null,null
Array with chunk size 5
1,2,3,4,5
6,7,8,9,null
for(int i=0;i<list.size();){
ArrayList<Integer>row = new ArrayList<Integer>();
int k=0;
while(k < chunksize){
chunk.add(list.get(i));
i++;
k++;
}
System.out.println(chunk);
nestedlist.add(chunk);
}
где список массив 1 размер и кусок является вложенной массив размера chunksize
Простой способ сделать это,
int loopcount = employeeList.size() / constCount;
int leftcount = employeeList.size() % constCount;
for (int i = 0; i < loopcount - 1; i++) {
//query.setParameterList("values"+i, employeeList.subList(tempCount, tempCount + constCount));
System.out.println(employeeList.subList(tempCount, tempCount + constCount));
tempCount = tempCount + 1000;
}