Java集合-TreeMap源码

数据结构

• 红黑树
• 实现了NavigableMap，是一个key有序的Map

源码

成员变量

private final Comparator<? super K> comparator;

private transient Entry<K,V> root;

/**
 * The number of entries in the tree
 */
private transient int size = 0;

/**
 * The number of structural modifications to the tree.
 */
private transient int modCount = 0;
           

构造函数

public TreeMap() {
    comparator = null;
}

public TreeMap(Comparator<? super K> comparator) {
    this.comparator = comparator;
}

public TreeMap(Map<? extends K, ? extends V> m) {
    comparator = null;
    putAll(m);
}

/**
 * Constructs a new tree map containing the same mappings and
 * using the same ordering as the specified sorted map.  This
 * method runs in linear time.
 */
public TreeMap(SortedMap<K, ? extends V> m) {
    comparator = m.comparator();
    try {
        buildFromSorted(m.size(), m.entrySet().iterator(), null, null);
    } catch (java.io.IOException cannotHappen) {
    } catch (ClassNotFoundException cannotHappen) {
    }
}