multiringidfactory.java

pastry的java实现的2.0b版

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"FreePastry" Peer-to-Peer Application Development Substrate 

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package rice.p2p.multiring;

import rice.environment.random.RandomSource;
import rice.p2p.commonapi.*;
import java.util.*;

/**
 * @(#) IdFactory.java This class provides the ability to build Ids which can
 * support a multi-ring hierarchy.
 *
 * @version $Id: MultiringIdFactory.java 2551 2005-06-06 19:01:02Z jeffh $
 * @author Alan Mislove
 * @author Peter Druschel
 */
public class MultiringIdFactory implements IdFactory {

  /**
   * The multiring node supporting this endpoint
   */
  protected Id ringId;

  /**
   * The underlying IdFactory
   */
  protected IdFactory factory;

  /**
   * Constructor
   *
   * @param factory the underlying factory to use
   * @param ringId DESCRIBE THE PARAMETER
   */
  public MultiringIdFactory(Id ringId, IdFactory factory) {
    this.ringId = ringId;
    this.factory = factory;
  }

  /**
   * Method which returns the underlying Id which represents the local node's
   * ring
   *
   * @return The Id represetning the local ring
   */
  public Id getRingId() {
    return ringId;
  }

  /**
   * Returns the length a Id.toString should be.
   *
   * @return The correct length;
   */
  public int getIdToStringLength() {
    return 4 + (2 * factory.getIdToStringLength());
  }

  /**
   * Builds a ringId by using the provided Id and ringIds.
   *
   * @param ringId The id to use as the ringid
   * @param material The id material to use
   * @return The built Id.
   */
  public RingId buildRingId(Id ringId, byte[] material) {
    return RingId.build(ringId, factory.buildId(material));
  }

  /**
   * Builds a ringId by using the provided Id and ringIds.
   *
   * @param ringId The id to use as the ringid
   * @param id The id to use as the id
   * @return The built Id.
   */
  public RingId buildRingId(Id ringId, Id id) {
    return RingId.build(ringId, id);
  }

  /**
   * Builds a protocol-specific Id given the source data.
   *
   * @param material The material to use
   * @return The built Id.
   */
  public Id buildNormalId(byte[] material) {
    return factory.buildId(material);
  }

  /**
   * Builds a protocol-specific Id given the source data.
   *
   * @param material The material to use
   * @return The built Id.
   */
  public Id buildNormalId(String material) {
    return factory.buildId(material);
  }

  /**
   * Builds a protocol-specific Id given the source data.
   *
   * @param material The material to use
   * @return The built Id.
   */
  public Id buildId(byte[] material) {
    return RingId.build(getRingId(), factory.buildId(material));
  }

  /**
   * Builds a protocol-specific Id given the source data.
   *
   * @param material The material to use
   * @return The built Id.
   */
  public Id buildId(int[] material) {
    return RingId.build(getRingId(), factory.buildId(material));
  }

  /**
   * Builds a protocol-specific Id by using the hash of the given string as
   * source data.
   *
   * @param string The string to use as source data
   * @return The built Id.
   */
  public Id buildId(String string) {
    return RingId.build(getRingId(), factory.buildId(string));
  }

  /**
   * Builds a random protocol-specific Id.
   *
   * @param rng A random number generator
   * @return The built Id.
   */
  public rice.p2p.commonapi.Id buildRandomId(Random rng) {
    return RingId.build(getRingId(), factory.buildRandomId(rng));
  }

  /**
   * DESCRIBE THE METHOD
   *
   * @param rng DESCRIBE THE PARAMETER
   * @return DESCRIBE THE RETURN VALUE
   */
  public rice.p2p.commonapi.Id buildRandomId(RandomSource rng) {
    return RingId.build(getRingId(), factory.buildRandomId(rng));
  }

  /**
   * Builds an Id by converting the given toString() output back to an Id.
   * Should not normall be used.
   *
   * @param string The toString() representation of an Id
   * @return The built Id.
   */
  public Id buildIdFromToString(String string) {
    string = string.substring(1);
    Id ring = factory.buildIdFromToString(string.substring(0, string.indexOf(",")));

    string = string.substring(string.indexOf(", ") + 2);
    Id normal = factory.buildIdFromToString(string.substring(0, string.length() - 1));

    return RingId.build(ring, normal);
  }

  /**
   * Builds an Id by converting the given toString() output back to an Id.
   * Should not normally be used.
   *
   * @param chars The character array
   * @param offset The offset to start reading at
   * @param length The length to read
   * @return The built Id.
   */
  public Id buildIdFromToString(char[] chars, int offset, int length) {
    Id ring = factory.buildIdFromToString(chars, 1, find(chars, ',') - 1);
    Id normal = factory.buildIdFromToString(chars, 2 + find(chars, ','), find(chars, ')') - (2 + find(chars, ',')));

    return RingId.build(ring, normal);
  }

  /**
   * Builds an IdRange based on a prefix. Any id which has this prefix should be
   * inside this IdRange, and any id which does not share this prefix should be
   * outside it.
   *
   * @param string The toString() representation of an Id
   * @return The built Id.
   */
  public IdRange buildIdRangeFromPrefix(String string) {
    if (string.indexOf(", ") < 0) {
      return new MultiringIdRange(ringId, factory.buildIdRangeFromPrefix(string));
    }

    string = string.substring(1);
    Id ring = factory.buildIdFromToString(string.substring(0, string.indexOf(", ")));

    string = string.substring(string.indexOf(", ") + 2);
    IdRange range = factory.buildIdRangeFromPrefix(string);

    return new MultiringIdRange(ring, range);
  }

  /**
   * Builds a protocol-specific Id.Distance given the source data.
   *
   * @param material The material to use
   * @return The built Id.Distance.
   */
  public Id.Distance buildIdDistance(byte[] material) {
    return factory.buildIdDistance(material);
  }

  /**
   * Creates an IdRange given the CW and CCW ids.
   *
   * @param cw The clockwise Id
   * @param ccw The counterclockwise Id
   * @return An IdRange with the appropriate delimiters.
   */
  public IdRange buildIdRange(Id cw, Id ccw) {
    return new MultiringIdRange(getRingId(), factory.buildIdRange(((RingId) cw).getId(), ((RingId) ccw).getId()));
  }

  /**
   * Creates an empty IdSet.
   *
   * @return an empty IdSet
   */
  public IdSet buildIdSet() {
    return new MultiringIdSet(getRingId(), factory.buildIdSet());
  }

  /**
   * Creates an empty IdSet.
   *
   * @param map DESCRIBE THE PARAMETER
   * @return an empty IdSet
   */
  public IdSet buildIdSet(SortedMap map) {
    return new MultiringIdSet(getRingId(), factory.buildIdSet(new MultiringSortedMap(map)));
  }

  /**
   * Creates an empty NodeHandleSet.
   *
   * @return an empty NodeHandleSet
   */
  public NodeHandleSet buildNodeHandleSet() {
    return new MultiringNodeHandleSet(getRingId(), factory.buildNodeHandleSet());
  }

  /**
   * DESCRIBE THE METHOD
   *
   * @param chars DESCRIBE THE PARAMETER
   * @param value DESCRIBE THE PARAMETER
   * @return DESCRIBE THE RETURN VALUE
   */
  protected static int find(char[] chars, char value) {
    for (int i = 0; i < chars.length; i++) {
      if (chars[i] == value) {
        return i;
      }
    }

    return chars.length;
  }

  /**
   * DESCRIBE THE CLASS
   *
   * @version $Id: pretty.settings 2305 2005-03-11 20:22:33Z jeffh $
   * @author jeffh
   */
  protected class MultiringSortedMap implements SortedMap {
    /**
     * DESCRIBE THE FIELD
     */
    protected SortedMap map;

    /**
     * Constructor for MultiringSortedMap.
     *
     * @param map DESCRIBE THE PARAMETER
     */
    public MultiringSortedMap(SortedMap map) {
      this.map = map;
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @param key DESCRIBE THE PARAMETER
     * @return DESCRIBE THE RETURN VALUE
     */
    public Object get(Object key) {
      throw new UnsupportedOperationException("get not supported!");
    }

    /**
     * Gets the Empty attribute of the MultiringSortedMap object
     *
     * @return The Empty value
     */
    public boolean isEmpty() {
      throw new UnsupportedOperationException("isEmpty not supported!");
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @return DESCRIBE THE RETURN VALUE
     */
    public Comparator comparator() {
      return null;
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @return DESCRIBE THE RETURN VALUE
     */
    public Object firstKey() {
      return (map.firstKey() == null ? null : ((RingId) map.firstKey()).getId());
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @param toKey DESCRIBE THE PARAMETER
     * @return DESCRIBE THE RETURN VALUE
     */
    public SortedMap headMap(Object toKey) {
      return map.headMap(RingId.build(ringId, (Id) toKey));
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @return DESCRIBE THE RETURN VALUE
     */
    public Object lastKey() {
      return (map.lastKey() == null ? null : ((RingId) map.lastKey()).getId());
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @param fromKey DESCRIBE THE PARAMETER
     * @param toKey DESCRIBE THE PARAMETER
     * @return DESCRIBE THE RETURN VALUE
     */
    public SortedMap subMap(Object fromKey, Object toKey) {
      return map.subMap(RingId.build(ringId, (Id) fromKey), RingId.build(ringId, (Id) toKey));
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @param fromKey DESCRIBE THE PARAMETER
     * @return DESCRIBE THE RETURN VALUE
     */
    public SortedMap tailMap(Object fromKey) {
      return map.tailMap(RingId.build(ringId, (Id) fromKey));
    }

    /**
     * DESCRIBE THE METHOD
     */
    public void clear() {
      throw new UnsupportedOperationException("clear not supported!");
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @param key DESCRIBE THE PARAMETER
     * @return DESCRIBE THE RETURN VALUE
     */
    public boolean containsKey(Object key) {
      return map.containsKey(RingId.build(ringId, (Id) key));
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @param value DESCRIBE THE PARAMETER
     * @return DESCRIBE THE RETURN VALUE
     */
    public boolean containsValue(Object value) {
      throw new UnsupportedOperationException("containsValue not supported!");
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @return DESCRIBE THE RETURN VALUE
     */
    public Set entrySet() {
      return new MultiringEntrySet(map.entrySet());
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @param o DESCRIBE THE PARAMETER
     * @return DESCRIBE THE RETURN VALUE
     */
    public boolean equals(Object o) {
      throw new UnsupportedOperationException("equals not supported!");
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @return DESCRIBE THE RETURN VALUE
     */
    public int hashCode() {
      throw new UnsupportedOperationException("hashCode not supported!");
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @return DESCRIBE THE RETURN VALUE
     */
    public Set keySet() {
      return new MultiringKeySet(map.keySet());
    }

    /**
     * DESCRIBE THE METHOD
     *
     * @param key DESCRIBE THE PARAMETER
     * @param value DESCRIBE THE PARAMETER
     * @return DESCRIBE THE RETURN VALUE
     */
    public Object put(Object key, Object value) {
      return map.put(RingId.build(ringId, (Id) key), value);
    }

    /**
     * DESCRIBE THE METHOD