Question

TreeSet的源代码如下所示：

public class TreeSet<E> extends AbstractSet<E>
implements NavigableSet<E>, Cloneable, java.io.Serializable
{
/**
 * The backing map.
 */
private transient NavigableMap<E,Object> m;

// Dummy value to associate with an Object in the backing Map
private static final Object PRESENT = new Object();

/**
 * Constructs a set backed by the specified navigable map.
 */
TreeSet(NavigableMap<E,Object> m) {
    this.m = m;
}

/**
 * Constructs a new, empty tree set, sorted according to the
 * natural ordering of its elements.  All elements inserted into
 * the set must implement the {@link Comparable} interface.
 * Furthermore, all such elements must be <i>mutually
 * comparable</i>: {@code e1.compareTo(e2)} must not throw a
 * {@code ClassCastException} for any elements {@code e1} and
 * {@code e2} in the set.  If the user attempts to add an element
 * to the set that violates this constraint (for example, the user
 * attempts to add a string element to a set whose elements are
 * integers), the {@code add} call will throw a
 * {@code ClassCastException}.
 */
public TreeSet() {
    this(new TreeMap<E,Object>());
}

在这里，我们观察到虽然引用的类型为NaviagableMap，但基础数据结构为TreeMap。

我的问题是为何将其标记为transient？不知道这会导致丢失任何TreeSet对象的传输能力吗？

为什么TreeSet中的基础数据结构标记为瞬态

0 个答案: