Class ConcurrentHashMap

classpath/java/util/concurrent/ConcurrentHashMap.java:25–438

import java.util.NoSuchElementException;

public class ConcurrentHashMap<K,V>
  extends AbstractMap<K,V>
  implements ConcurrentMap<K,V>
{
  private static final Unsafe unsafe = Unsafe.getUnsafe();
  private static final long Content;
  private static final Content Empty = new Content(new PersistentSet(), 0);

  static {
    try {
      Content = unsafe.objectFieldOffset
        (ConcurrentHashMap.class.getDeclaredField("content"));
    } catch (NoSuchFieldException e) {
      throw new Error(e);
    }
  }

  private volatile Content<K,V> content;

  public ConcurrentHashMap() {
    content = Empty;
  }

  public ConcurrentHashMap(int initialCapacity) {
    this();
  }

  public ConcurrentHashMap(int initialCapacity,  float loadFactor) {
    this();
  }

  public ConcurrentHashMap(int initialCapacity,  float loadFactor, int concurrencyLevel) {
    this();
  }

  public boolean isEmpty() {
    return content.size == 0;
  }

  public int size() {
    return content.size;
  }

  public boolean containsKey(Object key) {
    return find(key) != null;
  }

  public boolean containsValue(Object value) {
    for (V v: values()) {
      if (value.equals(v)) {
        return true;
      }
    }
    return false;
  }

  public V get(Object key) {
    Cell<K,V> cell = find(key);