arraycopy()的简单使用
public static native void arraycopy(Object src, int srcPos, Object dest, int destPos,int length);
参数：
src：要复制的数组(源数组)
srcPos：复制源数组的起始位置
dest：目标数组
destPos：目标数组的下标位置
length：要复制的长度
String[] arr = {"A","B","C","D","E","F"};
System.arraycopy(arr ,0,arr1,0,arr.length);
