解决Arrays.asList()使用remove（）、add（）方法时报java.lang.UnsupportedOperationException

List strList = Arrays.asList("a", "b", "c");
        if (strList.contains("a")) {
            strList.remove("a");
        }

以上代码对list.remove()会报java.lang.UnsupportedOperationException，开始查找原因：aslist()是new ArrayList

public static  List asList(T... a) {
        return new ArrayList<>(a);
    }

此ArrayList与java.util.ArrayList一样继承了AbstractList,不同点在于Arrays.aslist 没有重写remove，add等方法。

 private static class ArrayList extends AbstractList
        implements RandomAccess, java.io.Serializable
    {
        private static final long serialVersionUID = -2764017481108945198L;
        private final E[] a;

        ArrayList(E[] array) {
            a = Objects.requireNonNull(array);
        }

 从上可知，Arrays.aslist 调用remove,add等方法，直接抛出java.lang.UnsupportedOperationException异常，而java.util.ArrayList重写后的remove方法如下：

解决方案：用java.util.ArrayList包装

public class CollectionsTest {
    public static void main(String[] args) {
        List strList = Arrays.asList("a", "b", "c");
        ArrayList newList = new ArrayList<>(strList);
        if (newList.contains("a")) {
            newList.remove("a");
            System.out.println(newList);
        }
    }
}

输出：[b,c]