JAVA要用什么方法来更新数组

String[] a = new String[]{"aaa","ccc","ddd"}
String[] b = new String[]{"aaa","ccc","ddd"};
String[] c = new String[]{"aaa","bbb","ccc","ddd","eee","fff"};

            比如有一个a数组一种操是更新a数组,把b里面和a不同的元素更新到a里面,第二种操作上是把a里面没有的b的元素插入到a中,求方法啊~~

新手吧,遍历比较呗;或者转成List,List的contain方法可以判断元素在不在集合里。

public static String[] arrayCombine(String[] a, String[] b) {
    if (a == null || b == null)
        return null;
    List<String> aList = new ArrayList<String>();
    Collections.addAll(aList, a);
    List<String> bList = new ArrayList<String>();
    Collections.addAll(bList, b);
    for (String bStr : bList) {
        if (!aList.contains(bStr)) {
            aList.add(bStr);
        }
    }
    return aList.toArray(new String[] {});
}

List alist=Arrays.asList(a);
for(int i=0 ;i<b.length;i++){
int index=Arrays.binarySearch(a,b[i]);
if(index==-1){
alist.add(b[i]);
}
}
b里面和a不同的元素,把a里面没有的b的元素。这两句话不是一个意思么?

数组扩容,我粘一段代码:

String str1 = {"aaa", "bbb"};
String str2 = {"ccc", "ddd"};

int str1Len = str1.length;
int str2Len = str2.length;

str1 = Arrays.copyof(str1, str1Len+str2Len);
System.arrayCopy(str2, 0, str1, str1Len, str2Len);
System.out.println(Arrays.toString(str1));