java,Arrays.asList用法

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import java.util.Arrays;
import java.util.List;

public class Main {

    public static void main(String[] args) {
//        String[] arr = new String[]{"0.56", "1.23", "0", "12.2", "78", "123.6"};//正确
//        List<String> list = Arrays.asList(arr);
//        List<String> list = Arrays.asList("","1","2","3");//正确
//        List<String> list = Arrays.asList();//正确
        List<String> list = Arrays.asList(null);//错误，NullPointerException
        System.out.println(list);
    }

}

源码（JDK1.8）：

    /**
     * Returns a fixed-size list backed by the specified array.  (Changes to
     * the returned list "write through" to the array.)  This method acts
     * as bridge between array-based and collection-based APIs, in
     * combination with {@link Collection#toArray}.  The returned list is
     * serializable and implements {@link RandomAccess}.
     *
     * <p>This method also provides a convenient way to create a fixed-size
     * list initialized to contain several elements:
     * <pre>
     *     List&lt;String&gt; stooges = Arrays.asList("Larry", "Moe", "Curly");
     * </pre>
     *
     * @param <T> the class of the objects in the array
     * @param a the array by which the list will be backed
     * @return a list view of the specified array
     */
    @SafeVarargs
    @SuppressWarnings("varargs")
    public static <T> List<T> asList(T... a) {
        return new ArrayList<>(a);
    }

T... a , 传入数组或者多个字符串均可