为什么我不能在java中复制数组的一部分？

Question

I'm new to java, but have done some programming in other languages before. I have an array that I declared. This one is for the basic equipment, and each of the basicSimple* have been correctly declared earlier on:

//Creating template...
Item[] basicSet = new Item[15];
basicSet [0] = basicSimpleShoes;
basicSet [2] = basicSimplePants;
basicSet [4] = basicSimpleShirt;
basicSet [6] = basicSimpleGloves;

I'm trying to copy the array to some other ones, each for one of the possible formats, one of which looks like this:

//Strongarm set...
Item[] strongarmBeginnerSet = new Item[15];
strongarmBeginnerSet [0,6] = basicSet[0,6];
strongarmBeginnerSet [9] = basicSimpleShortsword;
strongarmBeginnerSet [10] = basicSimpleShield;

Again, the basicSimple* Items are correctly declared earlier on. I keep on getting an error, something about a missing closing bracket, but I can't find where it is. Do I have to declare each piece individually or is there a function I'm unaware of for this scenario?

Answer 1

This simply won't work in Java, the slice notation exists for other programming languages (say, Python), but not in Java:

strongarmBeginnerSet[0,6] = basicSet[0,6]; // compiler reports a syntax error!

You have to copy each element in turn, like this (and I'm assuming that you intended to copy up to and including the seventh element located at index 6 ):

for (int i = 0; i < 7; i++)
    strongarmBeginnerSet[i] = basicSet[i];

Or alternatively, use System.arraycopy() :

System.arraycopy(basicSet, 0, strongarmBeginnerSet, 0, 7);

Answer 2

strongarmBeginnerSet [0,6] = basicSet[0,6]; is not valid syntax in Java. You will need to use a for loop instead.

Answer 3

strongarmBeginnerSet [0,6] = basicSet[0,6]; is invalid syntax for Java.

You could use System.arraycopy to achieve the same result...

Something like...

System.arraycopy(basicSet, 0, strongarmBeginnerSet, 0, 6);

For example...

Answer 4

要复制数组的一部分，请使用：

strongarmBeginnerSet [6] = Arrays.asList(basicSet).subList(0,7).toArray();