[Google Maps] Dévélopper une application de géolocalisation

Dévélopper une application de géolocalisation

Je souhaite développé une application de géolocalisation pour des équipements tels que les décodeurs histoire d'optimiser les interventions des techniciens chez les clients abonnés d'un Fournisseur d'Accès internet /Télévision Numérique & Téléphonie.
Je suis novice dans le développement sur Google Maps API V3 et j'ai besoin des conseils pour démarrer mon projet ainsi que des Tutos qui pourront m'aider.

Bonjour,
difficile de répondre juste comme cela!

L'intégration d'un Map Google ne relève d'aucun exploit.
:fleche: FAQ API Google Maps

La géolocalisation ce fait tout aussi simplement
:fleche: L'API geolocalisation en HTML5

Pour le reste il s'agit de la gestion d'une base de données et de l'interrogation de celles ci.

Mais pour commencer il suffit de bien définir son besoin ;)

Afficher les marquers de différentes couleurs

Bonsoir à tous J'ai avancé dans mon application de géolocalisation et elle est presque en phase terminale. Je devais attaquer une base de données de monitoring pour afficher l'état de mes équipements et leur emplacement sur la carte Google Maps. C'est à dire lorsque l'équipement est Up j'affiche le marqueur vert et lorsque l'équipement est Down j'affiche le marqueur Rouge. J'ai regardé un exemple sur google et on m'a conseillé ce code
Code:

1 2 3 4 5 6 7 8 var customIcons = { restaurant: { icon: 'image1.png' }, bar: { icon: 'image2.png' } };
Mais la table avec laquelle je travaille dans ma base de données cet attribut est un entier donc l'attribut Status vaut 1 quand l'équipement est Up et 2 quand l'équipement est Down.
Du coup j'ai transformé le code en
Code:

1 2 3 4 5 6 7 8 var customIcons = { 1: { icon: 'image1.png' }, 2: { icon: 'image2.png' } };
Mais malheureusement il ne fonctionne pas. je voudrais savoir comment je peux appliquer cette structure avec des entiers et non des chaines de caractères.

Citation:

Mais malheureusement il ne fonctionne pas. je voudrais savoir comment je peux appliquer cette structure avec des entiers et non des chaines de caractères.

Ta deuxième syntaxe est tout à fait correcte seulement pour l'appel il faut faire

Code:

console.log( customIcons[2].icon); // affiche image2.png

Dans ton cas pourquoi ne pas plutôt passer par un Array si tu n'a pas plus de chose à mettre dans tes objets.

Google Maps API V3

Merci pour l'aide mais je sais pas à quel niveau je suis sensé faire l'appel.
Voici l'intégralité.

Code:

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<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <meta http-equiv="content-type" content="text/html; charset=utf-8"/>
    <title>Google Maps AJAX + mySQL/PHP Example</title>
    <script src="http://maps.google.com/maps/api/js?sensor=false"
            type="text/javascript"></script>
    <script type="text/javascript">
    //<![CDATA[
    // Je veux donc afficher le marker 4 quand l'attribut type vaut 1 et le marker 3 quand l'attribut type vaut 2
    var customIcons = {
      1: {
        icon: 'marker4.png',
      },
      2: {
        icon: 'marker3.png',
      }
    };
 
    function load() {
      var map = new google.maps.Map(document.getElementById("map"), {
        center: new google.maps.LatLng(47.6145, -122.3418),
        zoom: 13,
        mapTypeId: 'roadmap'
      });
      var infoWindow = new google.maps.InfoWindow;
 
      // Change this depending on the name of your PHP file
      downloadUrl("phpsqlajax_genxml2.php", function(data) {
        var xml = data.responseXML;
        var markers = xml.documentElement.getElementsByTagName("marker");
        for (var i = 0; i < markers.length; i++) {
          var name = markers[i].getAttribute("name");
          var address = markers[i].getAttribute("address");
          var type = markers[i].getAttribute("type");
          var point = new google.maps.LatLng(
              parseFloat(markers[i].getAttribute("lat")),
              parseFloat(markers[i].getAttribute("lng")));
          var html = "<b>" + name + "</b> <br/>" + address;
          var icon = customIcons[type] || {};
          var marker = new google.maps.Marker({
            map: map,
            position: point,
            icon: icon.icon,
            shadow: icon.shadow
          });
          bindInfoWindow(marker, map, infoWindow, html);
        }
      });
    }
 
    function bindInfoWindow(marker, map, infoWindow, html) {
      google.maps.event.addListener(marker, 'click', function() {
        infoWindow.setContent(html);
        infoWindow.open(map, marker);
      });
    }
 
    function downloadUrl(url, callback) {
      var request = window.ActiveXObject ?
          new ActiveXObject('Microsoft.XMLHTTP') :
          new XMLHttpRequest;
 
      request.onreadystatechange = function() {
        if (request.readyState == 4) {
          request.onreadystatechange = doNothing;
          callback(request, request.status);
        }
      };
 
      request.open('GET', url, true);
      request.send(null);
    }
 
    function doNothing() {}
 
    //]]>
  </script>
  </head>
 
  <body onload="load()">
    <div id="map" style="width: 100%; height: 100%"></div>
  </body>
</html>

C'est la page HTML qui lance la carte. j'ai un fichier php qui se charge de récupérer les informations dans la base de données et le parser en xml.

Dans ce que tu proposes je vois au moins une erreur
Code:

1 2 3 4 5 6 var marker = new google.maps.Marker({ map: map, position: point, icon: icon.icon, shadow: icon.shadow // icon.shadow N'EST PAS DEFINI });
et une interrogation
Code:

1 2 downloadUrl("phpsqlajax_genxml2.php", function(data) { var xml = data.responseXML;
es tu sûr que data est au format XMLHttpRequest?

Google Maps API V3

Oui Data est au format XMLHTTPRequest. Le problème est que j'ai regardé dans ma base de données j'ai prit un attribut qui est une chaine de caractères(Protocole) j'ai fait le test ça passe normalement les icônes rouges pour SNMP et vertes pour ICMP s'affichent normalement. c'est pourquoi je suis sûre que mon problème viens de ma structure javascript suivante.
Code:

1 2 3 4 5 6 7 8 9 10 var customIcons = { 1: { icon: 'green.png' }, bar: { 2: 'red.png' } }; var icon = customIcons[Status] || {};
Car avec l'attribut chaîne de caractère le code fonctionne à merveille.
Code:

1 2 3 4 5 6 7 8 9 10 var customIcons = { SNMP: { icon: 'green.png' }, ICMP: { icon: 'red.png' } }; var icon = customIcons[Protocole] || {};
Et c'est la table avec la chaine de caractère que je dois utilisé donc je sais plus comment faire.
Aurez vous une solution.

!!!!

Regarde bien les 2 structures que tu proposes, elles ne sont PAS IDENTIQUES !

Google Maps API V3

je ne vois pas la différence elle est a quelle niveau. Mon problème est que cherche comment pouvoir utiliser les entiers avec ce type de structure pour pouvoir afficher 2 couleurs de maqueurs le vert lorsque le Status = 1 et le rouge lorsque Status = 2. est ce que c'est possible? Puisque avec les entiers ça passe normalement.

c'est le jeux des 7 erreurs
Code:

1 2 3 4 5 6 7 8 var customIcons = { 1: { icon: 'green.png' }, bar: { 2: 'red.png' } };
et il te faudra choisir entre status et protocole.

Google Maps API V3

Oui C'est vrai dans ma base de données SQL Server la table que je manipule s'appelle dbo.nodes. Maintenant l'attribut que je dois utilisé c'est Status car c'est cette table qui me renseigne sur l'état propre des équipements monitoré. Status = 1 lorsque l'équipement est Up et Status = 2 lorsque l'équipement est Down.
C'est pour cela que j'ai utilisé cette structure
Code:

1 2 3 4 5 6 7 8 var customIcons = { 1: { icon: 'Vert.png' }, 2: { icon: 'red.png' } };
Mais elle ne fonctionne pas. pour voir si le code avait un problème j'ai donc prit pour les test l'attribut Protocole (Puisque l'attribut protocole ne résous pas mon problème je ne peux pas l'utiliser c'est juste pour tester) j'ai donc éssayé ce code
Code:

1 2 3 4 5 6 7 8 var customIcons = { SNMP: { icon: 'Vert.png' }, ICMP: { icon: 'red.png' } };
Et je me suis rendu compte que cela fonctionnait bien les marqueurs changeait de couleur vert pour les équipements managé par le protocole SNMP et rouge pour ceux managés par le protocole ICMP. Mais ceci ne me sers absolument à rien.
J'aimerais qu'on me corrige la structure avec les entiers 1 et 2 Car le code que vous m'avez proposé n'est pas adéquat.

Es tu sûr que les valeurs extraites sont 1 et 2 et qu'il n'y a pas de caractères parasites comme un espace après par exemple.

1 pièce(s) jointe(s)

Google Maps API V3

En effet voici une capture de la table Status comme vous voyez il y'a des équipements dont le Status vaut 1 ils sont Up et ceux dont le Status vaut 2 ils sont Down. Je voudrait donc que ma structure me permette d'afficher un marqueur de couleur différente selon la valeur de l'attribut Status. Le type de status dans la base est Status(char(20),null). Alors que l'attribut qui marchait bien mais qui n'est pas nécessaire est Protocol(nvarchar(50),null). C'est peut être à ce niveau que la différence ce joue mais je sait pas à quel niveau. J'attends vos suggestion. Merci
Pièce jointe 140391

Si tu ne sais pas à partir de TES donées générer TON fichier XML alors essaie de faire un

Code:

var type = parseInt (markers[i].getAttribute("type"));

Google Maps API V3

C'est parfait mon application fonctionne parfaitement. Il fallait faire le ParseInt sur la variable Status. Ma carte Google Maps s'affiche avec les marqueurs rouges lorsque l'équipement est Down (Status = Down) et vert lorsque l'équipement est Up (Status = Up). Je continue quand même à avancé et j'ai toujours besoin de vous car maintenant que les équipements sont représentés sur la carte je veux pouvoir tracer un itinéraire entre deux équipements. c'est à dire lorsque la carte est ouverte je veux choisir un bouton qui me dirait par exemple tracer un itinéraire et je pourrai dessiner l'itinéraire avec ma souris suivant les directions que je choisirais comme le fait par exemple Google Map Maker. J'ai fait des recherches pour savoir comment avoir le code de Google Map Maker ou comment avoir une documentation pour adapter certaines fonctionnalités de MapMaker à mon application. J'ai trouver ce code je l'ai étudié je ne sais pas si il résoudra mon problème mais je vous le présente quand même.

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/*
 * Copyright (C) 2009 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
package com.google.common.collect;
 
import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.base.FinalizableReferenceQueue;
import com.google.common.base.FinalizableSoftReference;
import com.google.common.base.FinalizableWeakReference;
import com.google.common.base.Function;
import com.google.common.collect.CustomConcurrentHashMap.ComputingStrategy;
import com.google.common.collect.CustomConcurrentHashMap.Internals;
 
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.lang.ref.SoftReference;
import java.lang.ref.WeakReference;
import java.lang.reflect.Field;
import java.util.Map;
import java.util.TimerTask;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.TimeUnit;
 
/**
 * A {@link ConcurrentMap} builder, providing any combination of these
 * features: {@linkplain SoftReference soft} or {@linkplain WeakReference
 * weak} keys, soft or weak values, timed expiration, and on-demand
 * computation of values. Usage example: <pre> {@code
 *
 *   ConcurrentMap<Key, Graph> graphs = new MapMaker()
 *       .concurrencyLevel(32)
 *       .softKeys()
 *       .weakValues()
 *       .expiration(30, TimeUnit.MINUTES)
 *       .makeComputingMap(
 *           new Function<Key, Graph>() {
 *             public Graph apply(Key key) {
 *               return createExpensiveGraph(key);
 *             }
 *           });}</pre>
 *
 * These features are all optional; {@code new MapMaker().makeMap()}
 * returns a valid concurrent map that behaves exactly like a
 * {@link ConcurrentHashMap}.
 *
 * The returned map is implemented as a hash table with similar performance
 * characteristics to {@link ConcurrentHashMap}. It supports all optional
 * operations of the {@code ConcurrentMap} interface. It does not permit
 * null keys or values. It is serializable; however, serializing a map that
 * uses soft or weak references can give unpredictable results.
 *
 * <p><b>Note:</b> by default, the returned map uses equality comparisons
 * (the {@link Object#equals(Object) equals} method) to determine equality
 * for keys or values. However, if {@link #weakKeys()} or {@link
 * #softKeys()} was specified, the map uses identity ({@code ==})
 * comparisons instead for keys. Likewise, if {@link #weakValues()} or
 * {@link #softValues()} was specified, the map uses identity comparisons
 * for values.
 *
 * <p>The returned map has <i>weakly consistent iteration</i>: an iterator
 * over one of the map's view collections may reflect some, all or none of
 * the changes made to the map after the iterator was created.
 *
 * <p>An entry whose key or value is reclaimed by the garbage collector
 * immediately disappears from the map. (If the default settings of strong
 * keys and strong values are used, this will never happen.) The client can
 * never observe a partially-reclaimed entry. Any {@link java.util.Map.Entry}
 * instance retrieved from the map's {@linkplain Map#entrySet() entry set}
 * is snapshot of that entry's state at the time of retrieval.
 *
 * <p>{@code new MapMaker().weakKeys().makeMap()} can almost always be
 * used as a drop-in replacement for {@link java.util.WeakHashMap}, adding
 * concurrency, asynchronous cleanup, identity-based equality for keys, and
 * great flexibility.
 *
 * @author Bob Lee
 * @author Kevin Bourrillion
 */
@GwtCompatible(emulated = true)
public final class MapMaker {
  private Strength keyStrength = Strength.STRONG;
  private Strength valueStrength = Strength.STRONG;
  private long expirationNanos = 0;
  private boolean useCustomMap;
  private final CustomConcurrentHashMap.Builder builder
      = new CustomConcurrentHashMap.Builder();
 
  /**
   * Constructs a new {@code MapMaker} instance with default settings,
   * including strong keys, strong values, and no automatic expiration.
   */
  public MapMaker() {}
 
  /**
   * Sets a custom initial capacity (defaults to 16). Resizing this or
   * any other kind of hash table is a relatively slow operation, so,
   * when possible, it is a good idea to provide estimates of expected
   * table sizes.
   *
   * @throws IllegalArgumentException if {@code initialCapacity} is
   *   negative
   * @throws IllegalStateException if an initial capacity was already set
   */
  public MapMaker initialCapacity(int initialCapacity) {
    builder.initialCapacity(initialCapacity);
    return this;
  }
 
  /**
   * Guides the allowed concurrency among update operations. Used as a
   * hint for internal sizing. The table is internally partitioned to try
   * to permit the indicated number of concurrent updates without
   * contention.  Because placement in hash tables is essentially random,
   * the actual concurrency will vary. Ideally, you should choose a value
   * to accommodate as many threads as will ever concurrently modify the
   * table. Using a significantly higher value than you need can waste
   * space and time, and a significantly lower value can lead to thread
   * contention. But overestimates and underestimates within an order of
   * magnitude do not usually have much noticeable impact. A value of one
   * is appropriate when it is known that only one thread will modify and
   * all others will only read. Defaults to 16.
   *
   * @throws IllegalArgumentException if {@code concurrencyLevel} is
   *     nonpositive
   * @throws IllegalStateException if a concurrency level was already set
   */
  @GwtIncompatible("java.util.concurrent.ConcurrentHashMap concurrencyLevel")
  public MapMaker concurrencyLevel(int concurrencyLevel) {
    builder.concurrencyLevel(concurrencyLevel);
    return this;
  }
 
  /**
   * Specifies that each key (not value) stored in the map should be
   * wrapped in a {@link WeakReference} (by default, strong references
   * are used).
   *
   * <p><b>Note:</b> the map will use identity ({@code ==}) comparison
   * to determine equality of weak keys, which may not behave as you expect.
   * For example, storing a key in the map and then attempting a lookup
   * using a different but {@link Object#equals(Object) equals}-equivalent
   * key will always fail.
   *
   * @throws IllegalStateException if the key strength was already set
   * @see WeakReference
   */
  @GwtIncompatible("java.lang.ref.WeakReference")
  public MapMaker weakKeys() {
    return setKeyStrength(Strength.WEAK);
  }
 
  /**
   * Specifies that each key (not value) stored in the map should be
   * wrapped in a {@link SoftReference} (by default, strong references
   * are used).
   *
   * <p><b>Note:</b> the map will use identity ({@code ==}) comparison
   * to determine equality of soft keys, which may not behave as you expect.
   * For example, storing a key in the map and then attempting a lookup
   * using a different but {@link Object#equals(Object) equals}-equivalent
   * key will always fail.
   *
   * @throws IllegalStateException if the key strength was already set
   * @see SoftReference
   */
  @GwtIncompatible("java.lang.ref.SoftReference")
  public MapMaker softKeys() {
    return setKeyStrength(Strength.SOFT);
  }
 
  private MapMaker setKeyStrength(Strength strength) {
    if (keyStrength != Strength.STRONG) {
      throw new IllegalStateException("Key strength was already set to "
          + keyStrength + ".");
    }
    keyStrength = strength;
    useCustomMap = true;
    return this;
  }
 
  /**
   * Specifies that each value (not key) stored in the map should be
   * wrapped in a {@link WeakReference} (by default, strong references
   * are used).
   *
   * <p>Weak values will be garbage collected once they are weakly
   * reachable. This makes them a poor candidate for caching; consider
   * {@link #softValues()} instead.
   *
   * <p><b>Note:</b> the map will use identity ({@code ==}) comparison
   * to determine equality of weak values. This will notably impact
   * the behavior of {@link Map#containsValue(Object) containsValue},
   * {@link ConcurrentMap#remove(Object, Object) remove(Object, Object)},
   * and {@link ConcurrentMap#replace(Object, Object, Object) replace(K, V, V)}.
   *
   * @throws IllegalStateException if the key strength was already set
   * @see WeakReference
   */
  @GwtIncompatible("java.lang.ref.WeakReference")
  public MapMaker weakValues() {
    return setValueStrength(Strength.WEAK);
  }
 
  /**
   * Specifies that each value (not key) stored in the map should be
   * wrapped in a {@link SoftReference} (by default, strong references
   * are used).
   *
   * <p>Soft values will be garbage collected in response to memory
   * demand, and in a least-recently-used manner. This makes them a
   * good candidate for caching.
   *
   * <p><b>Note:</b> the map will use identity ({@code ==}) comparison
   * to determine equality of soft values. This will notably impact
   * the behavior of {@link Map#containsValue(Object) containsValue},
   * {@link ConcurrentMap#remove(Object, Object) remove(Object, Object)},
   * and {@link ConcurrentMap#replace(Object, Object, Object) replace(K, V, V)}.
   *
   * @throws IllegalStateException if the value strength was already set
   * @see SoftReference
   */
  @GwtIncompatible("java.lang.ref.SoftReference")
  public MapMaker softValues() {
    return setValueStrength(Strength.SOFT);
  }
 
  private MapMaker setValueStrength(Strength strength) {
    if (valueStrength != Strength.STRONG) {
      throw new IllegalStateException("Value strength was already set to "
          + valueStrength + ".");
    }
    valueStrength = strength;
    useCustomMap = true;
    return this;
  }
 
  /**
   * Specifies that each entry should be automatically removed from the
   * map once a fixed duration has passed since the entry's creation.
   *
   * @param duration the length of time after an entry is created that it
   *     should be automatically removed
   * @param unit the unit that {@code duration} is expressed in
   * @throws IllegalArgumentException if {@code duration} is not positive
   * @throws IllegalStateException if the expiration time was already set
   */
  public MapMaker expiration(long duration, TimeUnit unit) {
    if (expirationNanos != 0) {
      throw new IllegalStateException("expiration time of "
          + expirationNanos + " ns was already set");
    }
    if (duration <= 0) {
      throw new IllegalArgumentException("invalid duration: " + duration);
    }
    this.expirationNanos = unit.toNanos(duration);
    useCustomMap = true;
    return this;
  }
 
  /**
   * Builds the final map, without on-demand computation of values. This method
   * does not alter the state of this {@code MapMaker} instance, so it can be
   * invoked again to create multiple independent maps.
   *
   * @param <K> the type of keys to be stored in the returned map
   * @param <V> the type of values to be stored in the returned map
   * @return a concurrent map having the requested features
   */
  public <K, V> ConcurrentMap<K, V> makeMap() {
    return useCustomMap
        ? new StrategyImpl<K, V>(this).map
        : new ConcurrentHashMap<K, V>(builder.getInitialCapacity(),
            0.75f, builder.getConcurrencyLevel());
  }
 
  /**
   * Builds a map that supports atomic, on-demand computation of values. {@link
   * Map#get} either returns an already-computed value for the given key,
   * atomically computes it using the supplied function, or, if another thread
   * is currently computing the value for this key, simply waits for that thread
   * to finish and returns its computed value. Note that the function may be
   * executed concurrently by multiple threads, but only for distinct keys.
   *
   * <p>If an entry's value has not finished computing yet, query methods
   * besides {@code get} return immediately as if an entry doesn't exist. In
   * other words, an entry isn't externally visible until the value's
   * computation completes.
   *
   * <p>{@link Map#get} on the returned map will never return {@code null}. It
   * may throw:
   *
   * <ul>
   * <li>{@link NullPointerException} if the key is null or the computing
   *     function returns null
   * <li>{@link ComputationException} if an exception was thrown by the
   *     computing function. If that exception is already of type {@link
   *     ComputationException}, it is propagated directly; otherwise it is
   *     wrapped.
   * </ul>
   *
   * <p><b>Note:</b> Callers of {@code get} <i>must</i> ensure that the key
   * argument is of type {@code K}. The {@code get} method accepts {@code
   * Object}, so the key type is not checked at compile time. Passing an object
   * of a type other than {@code K} can result in that object being unsafely
   * passed to the computing function as type {@code K}, and unsafely stored in
   * the map.
   *
   * <p>If {@link Map#put} is called before a computation completes, other
   * threads waiting on the computation will wake up and return the stored
   * value. When the computation completes, its new result will overwrite the
   * value that was put in the map manually.
   *
   * <p>This method does not alter the state of this {@code MapMaker} instance,
   * so it can be invoked again to create multiple independent maps.
   */
  public <K, V> ConcurrentMap<K, V> makeComputingMap(
      Function<? super K, ? extends V> computingFunction) {
    return new StrategyImpl<K, V>(this, computingFunction).map;
  }
 
  // Remainder of this file is private implementation details
 
  private enum Strength {
    WEAK {
      @Override boolean equal(Object a, Object b) {
        return a == b;
      }
      @Override int hash(Object o) {
        return System.identityHashCode(o);
      }
      @Override <K, V> ValueReference<K, V> referenceValue(
          ReferenceEntry<K, V> entry, V value) {
        return new WeakValueReference<K, V>(value, entry);
      }
      @Override <K, V> ReferenceEntry<K, V> newEntry(
          Internals<K, V, ReferenceEntry<K, V>> internals, K key,
          int hash, ReferenceEntry<K, V> next) {
        return (next == null)
            ? new WeakEntry<K, V>(internals, key, hash)
            : new LinkedWeakEntry<K, V>(internals, key, hash, next);
      }
      @Override <K, V> ReferenceEntry<K, V> copyEntry(
          K key, ReferenceEntry<K, V> original,
          ReferenceEntry<K, V> newNext) {
        WeakEntry<K, V> from = (WeakEntry<K, V>) original;
        return (newNext == null)
            ? new WeakEntry<K, V>(from.internals, key, from.hash)
            : new LinkedWeakEntry<K, V>(
                from.internals, key, from.hash, newNext);
      }
    },
 
    SOFT {
      @Override boolean equal(Object a, Object b) {
        return a == b;
      }
      @Override int hash(Object o) {
        return System.identityHashCode(o);
      }
      @Override <K, V> ValueReference<K, V> referenceValue(
          ReferenceEntry<K, V> entry, V value) {
        return new SoftValueReference<K, V>(value, entry);
      }
      @Override <K, V> ReferenceEntry<K, V> newEntry(
          Internals<K, V, ReferenceEntry<K, V>> internals, K key,
          int hash, ReferenceEntry<K, V> next) {
        return (next == null)
            ? new SoftEntry<K, V>(internals, key, hash)
            : new LinkedSoftEntry<K, V>(internals, key, hash, next);
      }
      @Override <K, V> ReferenceEntry<K, V> copyEntry(
          K key, ReferenceEntry<K, V> original,
          ReferenceEntry<K, V> newNext) {
        SoftEntry<K, V> from = (SoftEntry<K, V>) original;
        return (newNext == null)
            ? new SoftEntry<K, V>(from.internals, key, from.hash)
            : new LinkedSoftEntry<K, V>(
                from.internals, key, from.hash, newNext);
      }
    },
 
    STRONG {
      @Override boolean equal(Object a, Object b) {
        return a.equals(b);
      }
      @Override int hash(Object o) {
        return o.hashCode();
      }
      @Override <K, V> ValueReference<K, V> referenceValue(
          ReferenceEntry<K, V> entry, V value) {
        return new StrongValueReference<K, V>(value);
      }
      @Override <K, V> ReferenceEntry<K, V> newEntry(
          Internals<K, V, ReferenceEntry<K, V>> internals, K key,
          int hash, ReferenceEntry<K, V> next) {
        return (next == null)
            ? new StrongEntry<K, V>(internals, key, hash)
            : new LinkedStrongEntry<K, V>(
                internals, key, hash, next);
      }
      @Override <K, V> ReferenceEntry<K, V> copyEntry(
          K key, ReferenceEntry<K, V> original,
          ReferenceEntry<K, V> newNext) {
        StrongEntry<K, V> from = (StrongEntry<K, V>) original;
        return (newNext == null)
            ? new StrongEntry<K, V>(from.internals, key, from.hash)
            : new LinkedStrongEntry<K, V>(
                from.internals, key, from.hash, newNext);
      }
    };
 
    /**
     * Determines if two keys or values are equal according to this
     * strength strategy.
     */
    abstract boolean equal(Object a, Object b);
 
    /**
     * Hashes a key according to this strategy.
     */
    abstract int hash(Object o);
 
    /**
     * Creates a reference for the given value according to this value
     * strength.
     */
    abstract <K, V> ValueReference<K, V> referenceValue(
        ReferenceEntry<K, V> entry, V value);
 
    /**
     * Creates a new entry based on the current key strength.
     */
    abstract <K, V> ReferenceEntry<K, V> newEntry(
        Internals<K, V, ReferenceEntry<K, V>> internals, K key,
        int hash, ReferenceEntry<K, V> next);
 
    /**
     * Creates a new entry and copies the value and other state from an
     * existing entry.
     */
    abstract <K, V> ReferenceEntry<K, V> copyEntry(K key,
        ReferenceEntry<K, V> original, ReferenceEntry<K, V> newNext);
  }
 
  private static class StrategyImpl<K, V> implements Serializable,
      ComputingStrategy<K, V, ReferenceEntry<K, V>> {
    final Strength keyStrength;
    final Strength valueStrength;
    final ConcurrentMap<K, V> map;
    final long expirationNanos;
    Internals<K, V, ReferenceEntry<K, V>> internals;
 
    StrategyImpl(MapMaker maker) {
      this.keyStrength = maker.keyStrength;
      this.valueStrength = maker.valueStrength;
      this.expirationNanos = maker.expirationNanos;
 
      map = maker.builder.buildMap(this);
    }
 
    StrategyImpl(
        MapMaker maker, Function<? super K, ? extends V> computer) {
      this.keyStrength = maker.keyStrength;
      this.valueStrength = maker.valueStrength;
      this.expirationNanos = maker.expirationNanos;
 
      map = maker.builder.buildComputingMap(this, computer);
    }
 
    public void setValue(ReferenceEntry<K, V> entry, V value) {
      setValueReference(
          entry, valueStrength.referenceValue(entry, value));
      if (expirationNanos > 0) {
        scheduleRemoval(entry.getKey(), value);
      }
    }
 
    void scheduleRemoval(K key, V value) {
      /*
       * TODO: Keep weak reference to map, too. Build a priority
       * queue out of the entries themselves instead of creating a
       * task per entry. Then, we could have one recurring task per
       * map (which would clean the entire map and then reschedule
       * itself depending upon when the next expiration comes). We
       * also want to avoid removing an entry prematurely if the
       * entry was set to the same value again.
       */
      final WeakReference<K> keyReference = new WeakReference<K>(key);
      final WeakReference<V> valueReference = new WeakReference<V>(value);
      ExpirationTimer.instance.schedule(
          new TimerTask() {
            @Override public void run() {
              K key = keyReference.get();
              if (key != null) {
                // Remove if the value is still the same.
                map.remove(key, valueReference.get());
              }
            }
          }, TimeUnit.NANOSECONDS.toMillis(expirationNanos));
    }
 
    public boolean equalKeys(K a, Object b) {
      return keyStrength.equal(a, b);
    }
 
    public boolean equalValues(V a, Object b) {
      return valueStrength.equal(a, b);
    }
 
    public int hashKey(Object key) {
      return keyStrength.hash(key);
    }
 
    public K getKey(ReferenceEntry<K, V> entry) {
      return entry.getKey();
    }
 
    public int getHash(ReferenceEntry<K, V> entry) {
      return entry.getHash();
    }
 
    public ReferenceEntry<K, V> newEntry(
        K key, int hash, ReferenceEntry<K, V> next) {
      return keyStrength.newEntry(internals, key, hash, next);
    }
 
    public ReferenceEntry<K, V> copyEntry(K key,
        ReferenceEntry<K, V> original, ReferenceEntry<K, V> newNext) {
      ValueReference<K, V> valueReference = original.getValueReference();
      if (valueReference == COMPUTING) {
        ReferenceEntry<K, V> newEntry
            = newEntry(key, original.getHash(), newNext);
        newEntry.setValueReference(
            new FutureValueReference(original, newEntry));
        return newEntry;
      } else {
        ReferenceEntry<K, V> newEntry
            = newEntry(key, original.getHash(), newNext);
        newEntry.setValueReference(valueReference.copyFor(newEntry));
        return newEntry;
      }
    }
 
    /**
     * Waits for a computation to complete. Returns the result of the
     * computation or null if none was available.
     */
    public V waitForValue(ReferenceEntry<K, V> entry)
        throws InterruptedException {
      ValueReference<K, V> valueReference = entry.getValueReference();
      if (valueReference == COMPUTING) {
        synchronized (entry) {
          while ((valueReference = entry.getValueReference())
              == COMPUTING) {
            entry.wait();
          }
        }
      }
      return valueReference.waitForValue();
    }
 
    /**
     * Used by CustomConcurrentHashMap to retrieve values. Returns null
     * instead of blocking or throwing an exception.
     */
    public V getValue(ReferenceEntry<K, V> entry) {
      ValueReference<K, V> valueReference = entry.getValueReference();
      return valueReference.get();
    }
 
    public V compute(K key, final ReferenceEntry<K, V> entry,
        Function<? super K, ? extends V> computer) {
      V value;
      try {
        value = computer.apply(key);
      } catch (ComputationException e) {
        // if computer has thrown a computation exception, propagate rather
        // than wrap
        setValueReference(entry,
            new ComputationExceptionReference<K, V>(e.getCause()));
        throw e;
      } catch (Throwable t) {
        setValueReference(
          entry, new ComputationExceptionReference<K, V>(t));
        throw new ComputationException(t);
      }
 
      if (value == null) {
        String message
            = computer + " returned null for key " + key + ".";
        setValueReference(
            entry, new NullOutputExceptionReference<K, V>(message));
        throw new NullOutputException(message);
      } else {
        setValue(entry, value);
      }
      return value;
    }
 
    /**
     * Sets the value reference on an entry and notifies waiting
     * threads.
     */
    void setValueReference(ReferenceEntry<K, V> entry,
        ValueReference<K, V> valueReference) {
      boolean notifyOthers = (entry.getValueReference() == COMPUTING);
      entry.setValueReference(valueReference);
      if (notifyOthers) {
        synchronized (entry) {
          entry.notifyAll();
        }
      }
    }
 
    /**
     * Points to an old entry where a value is being computed. Used to
     * support non-blocking copying of entries during table expansion,
     * removals, etc.
     */
    private class FutureValueReference implements ValueReference<K, V> {
      final ReferenceEntry<K, V> original;
      final ReferenceEntry<K, V> newEntry;
 
      FutureValueReference(
          ReferenceEntry<K, V> original, ReferenceEntry<K, V> newEntry) {
        this.original = original;
        this.newEntry = newEntry;
      }
 
      public V get() {
        boolean success = false;
        try {
          V value = original.getValueReference().get();
          success = true;
          return value;
        } finally {
          if (!success) {
            removeEntry();
          }
        }
      }
 
      public ValueReference<K, V> copyFor(ReferenceEntry<K, V> entry) {
        return new FutureValueReference(original, entry);
      }
 
      public V waitForValue() throws InterruptedException {
        boolean success = false;
        try {
          // assert that key != null
          V value = StrategyImpl.this.waitForValue(original);
          success = true;
          return value;
        } finally {
          if (!success) {
            removeEntry();
          }
        }
      }
 
      /**
       * Removes the entry in the event of an exception. Ideally,
       * we'd clean up as soon as the computation completes, but we
       * can't do that without keeping a reference to this entry from
       * the original.
       */
      void removeEntry() {
        internals.removeEntry(newEntry);
      }
    }
 
    public ReferenceEntry<K, V> getNext(
        ReferenceEntry<K, V> entry) {
      return entry.getNext();
    }
 
    public void setInternals(
        Internals<K, V, ReferenceEntry<K, V>> internals) {
      this.internals = internals;
    }
 
    private static final long serialVersionUID = 0;
 
    private void writeObject(ObjectOutputStream out)
        throws IOException {
      // Custom serialization code ensures that the key and value
      // strengths are written before the map. We'll need them to
      // deserialize the map entries.
      out.writeObject(keyStrength);
      out.writeObject(valueStrength);
      out.writeLong(expirationNanos);
 
      // TODO: It is possible for the strategy to try to use the map
      // or internals during deserialization, for example, if an
      // entry gets reclaimed. We could detect this case and queue up
      // removals to be flushed after we deserialize the map.
      out.writeObject(internals);
      out.writeObject(map);
    }
 
    /**
     * Fields used during deserialization. We use a nested class so we
     * don't load them until we need them. We need to use reflection to
     * set final fields outside of the constructor.
     */
    private static class Fields {
      static final Field keyStrength = findField("keyStrength");
      static final Field valueStrength = findField("valueStrength");
      static final Field expirationNanos = findField("expirationNanos");
      static final Field internals = findField("internals");
      static final Field map = findField("map");
 
      static Field findField(String name) {
        try {
          Field f = StrategyImpl.class.getDeclaredField(name);
          f.setAccessible(true);
          return f;
        } catch (NoSuchFieldException e) {
          throw new AssertionError(e);
        }
      }
    }
 
    private void readObject(ObjectInputStream in)
        throws IOException, ClassNotFoundException {
      try {
        Fields.keyStrength.set(this, in.readObject());
        Fields.valueStrength.set(this, in.readObject());
        Fields.expirationNanos.set(this, in.readLong());
        Fields.internals.set(this, in.readObject());
        Fields.map.set(this, in.readObject());
      } catch (IllegalAccessException e) {
        throw new AssertionError(e);
      }
    }
  }
 
  /** A reference to a value. */
  private interface ValueReference<K, V> {
    /**
     * Gets the value. Does not block or throw exceptions.
     */
    V get();
 
    /** Creates a copy of this reference for the given entry. */
    ValueReference<K, V> copyFor(ReferenceEntry<K, V> entry);
 
    /**
     * Waits for a value that may still be computing. Unlike get(),
     * this method can block (in the case of FutureValueReference) or
     * throw an exception.
     */
    V waitForValue() throws InterruptedException;
  }
 
  private static final ValueReference<Object, Object> COMPUTING
      = new ValueReference<Object, Object>() {
    public Object get() {
      return null;
    }
    public ValueReference<Object, Object> copyFor(
        ReferenceEntry<Object, Object> entry) {
      throw new AssertionError();
    }
    public Object waitForValue() {
      throw new AssertionError();
    }
  };
 
  /**
   * Singleton placeholder that indicates a value is being computed.
   */
  @SuppressWarnings("unchecked")
  // Safe because impl never uses a parameter or returns any non-null value
  private static <K, V> ValueReference<K, V> computing() {
    return (ValueReference<K, V>) COMPUTING;
  }
 
  /** Used to provide null output exceptions to other threads. */
  private static class NullOutputExceptionReference<K, V>
      implements ValueReference<K, V> {
    final String message;
    NullOutputExceptionReference(String message) {
      this.message = message;
    }
    public V get() {
      return null;
    }
    public ValueReference<K, V> copyFor(
        ReferenceEntry<K, V> entry) {
      return this;
    }
    public V waitForValue() {
      throw new NullOutputException(message);
    }
  }
 
  /** Used to provide computation exceptions to other threads. */
  private static class ComputationExceptionReference<K, V>
      implements ValueReference<K, V> {
    final Throwable t;
    ComputationExceptionReference(Throwable t) {
      this.t = t;
    }
    public V get() {
      return null;
    }
    public ValueReference<K, V> copyFor(
        ReferenceEntry<K, V> entry) {
      return this;
    }
    public V waitForValue() {
      throw new AsynchronousComputationException(t);
    }
  }
 
  /** Wrapper class ensures that queue isn't created until it's used. */
  private static class QueueHolder {
    static final FinalizableReferenceQueue queue
        = new FinalizableReferenceQueue();
  }
 
  /**
   * An entry in a reference map.
   */
  private interface ReferenceEntry<K, V> {
    /**
     * Gets the value reference from this entry.
     */
    ValueReference<K, V> getValueReference();
 
    /**
     * Sets the value reference for this entry.
     *
     * @param valueReference
     */
    void setValueReference(ValueReference<K, V> valueReference);
 
    /**
     * Removes this entry from the map if its value reference hasn't
     * changed.  Used to clean up after values. The value reference can
     * just call this method on the entry so it doesn't have to keep
     * its own reference to the map.
     */
    void valueReclaimed();
 
    /** Gets the next entry in the chain. */
    ReferenceEntry<K, V> getNext();
 
    /** Gets the entry's hash. */
    int getHash();
 
    /** Gets the key for this entry. */
    public K getKey();
  }
 
  /**
   * Used for strongly-referenced keys.
   */
  private static class StrongEntry<K, V> implements ReferenceEntry<K, V> {
    final K key;
 
    StrongEntry(Internals<K, V, ReferenceEntry<K, V>> internals, K key,
        int hash) {
      this.internals = internals;
      this.key = key;
      this.hash = hash;
    }
 
    public K getKey() {
      return this.key;
    }
 
    // The code below is exactly the same for each entry type.
 
    final Internals<K, V, ReferenceEntry<K, V>> internals;
    final int hash;
    volatile ValueReference<K, V> valueReference = computing();
 
    public ValueReference<K, V> getValueReference() {
      return valueReference;
    }
    public void setValueReference(
        ValueReference<K, V> valueReference) {
      this.valueReference = valueReference;
    }
    public void valueReclaimed() {
      internals.removeEntry(this, null);
    }
    public ReferenceEntry<K, V> getNext() {
      return null;
    }
    public int getHash() {
      return hash;
    }
  }
 
  private static class LinkedStrongEntry<K, V> extends StrongEntry<K, V> {
 
    LinkedStrongEntry(Internals<K, V, ReferenceEntry<K, V>> internals,
        K key, int hash, ReferenceEntry<K, V> next) {
      super(internals, key, hash);
      this.next = next;
    }
 
    final ReferenceEntry<K, V> next;
 
    @Override public ReferenceEntry<K, V> getNext() {
      return next;
    }
  }
 
  /**
   * Used for softly-referenced keys.
   */
  private static class SoftEntry<K, V> extends FinalizableSoftReference<K>
      implements ReferenceEntry<K, V> {
    SoftEntry(Internals<K, V, ReferenceEntry<K, V>> internals, K key,
        int hash) {
      super(key, QueueHolder.queue);
      this.internals = internals;
      this.hash = hash;
    }
 
    public K getKey() {
      return get();
    }
 
    public void finalizeReferent() {
      internals.removeEntry(this);
    }
 
    // The code below is exactly the same for each entry type.
 
    final Internals<K, V, ReferenceEntry<K, V>> internals;
    final int hash;
    volatile ValueReference<K, V> valueReference = computing();
 
    public ValueReference<K, V> getValueReference() {
      return valueReference;
    }
    public void setValueReference(
        ValueReference<K, V> valueReference) {
      this.valueReference = valueReference;
    }
    public void valueReclaimed() {
      internals.removeEntry(this, null);
    }
    public ReferenceEntry<K, V> getNext() {
      return null;
    }
    public int getHash() {
      return hash;
    }
  }
 
  private static class LinkedSoftEntry<K, V> extends SoftEntry<K, V> {
    LinkedSoftEntry(Internals<K, V, ReferenceEntry<K, V>> internals,
        K key, int hash, ReferenceEntry<K, V> next) {
      super(internals, key, hash);
      this.next = next;
    }
 
    final ReferenceEntry<K, V> next;
 
    @Override public ReferenceEntry<K, V> getNext() {
      return next;
    }
  }
 
  /**
   * Used for weakly-referenced keys.
   */
  private static class WeakEntry<K, V> extends FinalizableWeakReference<K>
      implements ReferenceEntry<K, V> {
    WeakEntry(Internals<K, V, ReferenceEntry<K, V>> internals, K key,
        int hash) {
      super(key, QueueHolder.queue);
      this.internals = internals;
      this.hash = hash;
    }
 
    public K getKey() {
      return get();
    }
 
    public void finalizeReferent() {
      internals.removeEntry(this);
    }
 
    // The code below is exactly the same for each entry type.
 
    final Internals<K, V, ReferenceEntry<K, V>> internals;
    final int hash;
    volatile ValueReference<K, V> valueReference = computing();
 
    public ValueReference<K, V> getValueReference() {
      return valueReference;
    }
    public void setValueReference(
        ValueReference<K, V> valueReference) {
      this.valueReference = valueReference;
    }
    public void valueReclaimed() {
      internals.removeEntry(this, null);
    }
    public ReferenceEntry<K, V> getNext() {
      return null;
    }
    public int getHash() {
      return hash;
    }
  }
 
  private static class LinkedWeakEntry<K, V> extends WeakEntry<K, V> {
    LinkedWeakEntry(Internals<K, V, ReferenceEntry<K, V>> internals,
        K key, int hash, ReferenceEntry<K, V> next) {
      super(internals, key, hash);
      this.next = next;
    }
 
    final ReferenceEntry<K, V> next;
 
    @Override public ReferenceEntry<K, V> getNext() {
      return next;
    }
  }
 
  /** References a weak value. */
  private static class WeakValueReference<K, V>
      extends FinalizableWeakReference<V>
      implements ValueReference<K, V> {
    final ReferenceEntry<K, V> entry;
 
    WeakValueReference(V referent, ReferenceEntry<K, V> entry) {
      super(referent, QueueHolder.queue);
      this.entry = entry;
    }
 
    public void finalizeReferent() {
      entry.valueReclaimed();
    }
 
    public ValueReference<K, V> copyFor(
        ReferenceEntry<K, V> entry) {
      return new WeakValueReference<K, V>(get(), entry);
    }
 
    public V waitForValue() {
      return get();
    }
  }
 
  /** References a soft value. */
  private static class SoftValueReference<K, V>
      extends FinalizableSoftReference<V>
      implements ValueReference<K, V> {
    final ReferenceEntry<K, V> entry;
 
    SoftValueReference(V referent, ReferenceEntry<K, V> entry) {
      super(referent, QueueHolder.queue);
      this.entry = entry;
    }
 
    public void finalizeReferent() {
      entry.valueReclaimed();
    }
 
    public ValueReference<K, V> copyFor(
        ReferenceEntry<K, V> entry) {
      return new SoftValueReference<K, V>(get(), entry);
    }
 
    public V waitForValue() {
      return get();
    }
  }
 
  /** References a strong value. */
  private static class StrongValueReference<K, V>
      implements ValueReference<K, V> {
    final V referent;
 
    StrongValueReference(V referent) {
      this.referent = referent;
    }
 
    public V get() {
      return referent;
    }
 
    public ValueReference<K, V> copyFor(
        ReferenceEntry<K, V> entry) {
      return this;
    }
 
    public V waitForValue() {
      return get();
    }
  }
}

Comment l'adapter si c'est le code de Map Maker Sinon pourrez vous m'aidez à résoudre mon problème? Aurez vous une autre alternative.

Afin de ne pas obscurcir cette discussion je te propose de passer celle ci en résolue puis d’en ouvrir une autre portant sur ton nouveau soucis.

Je peux d'ores et déjà te dire 2 choses
- le code que tu as déniché est du java et donc rien à voir avec javascript
- regarde du coté de Création d'une Static Map à partir d'un itinéraire.

On en reparle dans une autre discussion ;)