我需要在Java中连接两个字符串数组。

void f(String[] first, String[] second) {
    String[] both = ???
}

哪种方法最简单?


当前回答

你可以试试这个

 public static Object[] addTwoArray(Object[] objArr1, Object[] objArr2){
    int arr1Length = objArr1!=null && objArr1.length>0?objArr1.length:0;
    int arr2Length = objArr2!=null && objArr2.length>0?objArr2.length:0;
    Object[] resutlentArray = new Object[arr1Length+arr2Length]; 
    for(int i=0,j=0;i<resutlentArray.length;i++){
        if(i+1<=arr1Length){
            resutlentArray[i]=objArr1[i];
        }else{
            resutlentArray[i]=objArr2[j];
            j++;
        }
    }

    return resutlentArray;
}

你可以键入你的数组!!!

其他回答

仅使用Java自己的API:


String[] join(String[]... arrays) {
  // calculate size of target array
  int size = 0;
  for (String[] array : arrays) {
    size += array.length;
  }

  // create list of appropriate size
  java.util.List list = new java.util.ArrayList(size);

  // add arrays
  for (String[] array : arrays) {
    list.addAll(java.util.Arrays.asList(array));
  }

  // create and return final array
  return list.toArray(new String[size]);
}

现在,这段代码不是最有效的,但它只依赖于标准的java类,而且很容易理解。它适用于任意数量的String[](甚至是零数组)。

我能找到的最简单的方法如下:


List allFiltersList = Arrays.asList(regularFilters);
allFiltersList.addAll(Arrays.asList(preFiltersArray));
Filter[] mergedFilterArray = (Filter[]) allFiltersList.toArray();

Import java.util.*;

String array1[] = {"bla","bla"};
String array2[] = {"bla","bla"};

ArrayList<String> tempArray = new ArrayList<String>(Arrays.asList(array1));
tempArray.addAll(Arrays.asList(array2));
String array3[] = films.toArray(new String[1]); // size will be overwritten if needed

您可以用自己喜欢的类型/类替换字符串

我确信这可以做得更短更好,但它很有效,我懒得进一步整理。。。

算法爱好者的另一个答案是:

public static String[] mergeArrays(String[] array1, String[] array2) {
    int totalSize = array1.length + array2.length; // Get total size
    String[] merged = new String[totalSize]; // Create new array
    // Loop over the total size
    for (int i = 0; i < totalSize; i++) {
        if (i < array1.length) // If the current position is less than the length of the first array, take value from first array
            merged[i] = array1[i]; // Position in first array is the current position

        else // If current position is equal or greater than the first array, take value from second array.
            merged[i] = array2[i - array1.length]; // Position in second array is current position minus length of first array.
    }

    return merged;

用法:

String[] array1str = new String[]{"a", "b", "c", "d"}; 
String[] array2str = new String[]{"e", "f", "g", "h", "i"};
String[] listTotalstr = mergeArrays(array1str, array2str);
System.out.println(Arrays.toString(listTotalstr));

结果:

[a, b, c, d, e, f, g, h, i]
public String[] concat(String[]... arrays)
{
    int length = 0;
    for (String[] array : arrays) {
        length += array.length;
    }
    String[] result = new String[length];
    int destPos = 0;
    for (String[] array : arrays) {
        System.arraycopy(array, 0, result, destPos, array.length);
        destPos += array.length;
    }
    return result;
}