title: error java.lang.NoSuchMethodError in java-mongodb example
body: <p>I have been trying to execute my first mongodb example in java. Its showing me the error. I have installed everything properly. Any help would be appreciated.it is throwing an exception Exception in thread "main" </p>
  
  <blockquote>
    <p>java.lang.NoSuchMethodError:
    com.mongodb.ReadPreference.primary()Lcom/mongodb/ReadPreference;  at
    com.mongodb.MongoClientOptions$Builder.(MongoClientOptions.java:731)
      at com.mongodb.MongoClient.(MongoClient.java:151)     at
    com.mongodb.MongoClient.(MongoClient.java:141)  at
    mongoDBExample.main(mongoDBExample.java:21)</p>
  </blockquote>
  
  <p>This is my program code.</p>
  
  <pre><code>   public class mongoDBExample {
      public static void main(String[] args) throws UnknownHostException {
  
      try {
  
      /**** Connect to MongoDB ****/
  
      MongoClient mongo = new MongoClient("localhost", 27017);
  
      /**** Get database ****/
      // if database doesn't exists, MongoDB will create it for you
      DB db = mongo.getDB("testdb");
  
      /**** Get collection / table from 'testdb' ****/
      // if collection doesn't exists, MongoDB will create it for you
      DBCollection table = db.getCollection("user");
  
      /**** Insert ****/
      // create a document to store key and value
  
  
      BasicDBObject document = new BasicDBObject();
      document.put("name", "mkyong");
      document.put("age", "30");
      document.put("createdDate", new Date());
      table.insert(new DBObject[] {document});
  
  
      /**** Find and display ****/
      BasicDBObject searchQuery = new BasicDBObject();
      searchQuery.put("name", "mkyong");
  
      DBCursor cursor = table.find(searchQuery);
  
      while (cursor.hasNext()) {
          System.out.println(cursor.next());
      }
  
      /**** Update ****/
      // search document where name="mkyong" and update it with new values
      BasicDBObject query = new BasicDBObject();
      query.put("name", "mkyong");
  
      BasicDBObject newDocument = new BasicDBObject();
      newDocument.put("name", "mkyong-updated");
  
      BasicDBObject updateObj = new BasicDBObject();
      updateObj.put("$set", newDocument);
  
      table.update(query, updateObj);
  
      /**** Find and display ****/
      BasicDBObject searchQuery2
          = new BasicDBObject().append("name", "mkyong-updated");
  
      DBCursor cursor2 = table.find(searchQuery2);
  
      while (cursor2.hasNext()) {
          System.out.println(cursor2.next());
      }
  
      /**** Done ****/
      System.out.println("Done");
  
      } catch (MongoException e) {
      e.printStackTrace();
      }
  
    }
  }
  </code></pre>