集合转换成数组，数组转换成集合

集合转换成数组

List<String> c = new ArrayList<String>();

c.add("one");

c.add(null);

c.add("two");

c.add("three");

c.add("");

c.add("four");

c.add("five");

System.out.println(c);

System.out.println(c.size());

Object[] array=c.toArray();

String[] array1=c.toArray(new String[5]);

System.out.println(Arrays.toString(array1));

System.out.println(Arrays.toString(array));

数组转换成集合

String[] array=new String[]{"one","two","three"};

List<String> list = Arrays.asList(array);

System.out.println(list);

//list.add("cc");

list.set(0, "1");

System.out.println(list);

System.out.println(Arrays.asList(array));

List<String> list1 = new ArrayList<String>(list);

System.out.println(list1);

list1.add("cc");

System.out.println(list1);

System.out.println(list);