SEARCH KEYWORD -- Map


  Why accessing Java HashMap may cause infinite loop in concurrent environment

HashMap in Java is frequently used to handle key/value pairs. But it is not a good candidate to be used in concurrent environment where ConcurrentHashMap should be used instead. If used in concurrent environment, it may cause lots of unexpected behavior even including make the program getting into an infinite loop situation. To understand how this can happen, let's first discuss how HaspMap works internally. In this post we will use implementation of HashMap before Java 8 as example, Java 8 prov...

   JAVA,HASHMAP,INFINITE LOOP     2020-03-29 01:47:00

  Difference between ConcurrentHashMap and Hashtable

Both ConcurrentHashMap and Hashtable are Collection classes for storing key value pairs and they both provide fast element search with a supplied key. They have much in common. However, we will not discuss the similarities between them here, instead we will focus on the differences between them. ConcurrentHashMap and Hashtable are both thread safe. But the mechanism for thread safe is different between them. Hashtable is synchronized, it utilizes the synchronization mechanism; while ConcurrentHa...

   ConcurrentHashMap,Hashtable     2013-11-18 08:06:54

  OpenLDAP Proxy -- Introduction

OpenLDAP is an open source project which is intended to provide some commercial-grade, fully featured applications and development tools based on the well known Light-weight Directory Access Protocol(LDAP). Hence corporations which want to manage their user and group information can freely use these tools.  OpenLDAP provides ldap servers, ldap clients and corresponding tools to work on LDAP. The LDAP server is called slapd(Stand-alone LDAP  daemon). And it would serve as the server whi...

   META,OPENLDAP,OPENLDAP PROXY,SLAPD,SLAPD.CONF,LDAP     2017-10-28 11:20:00

  Focus of Baidu in the future

In addition to the new generation "Baidu ladies", The biggest highlight of the annual meeting of Baidu is undoubtedly the passionate speech delivered by CEO Yanhong Li with a "Zoro" suite. He emphasized four business focus of Baidu in the future, i.e the traditional search, mobile cloud, LBS and international strategy. Although the strategy is clear, but what's more important is that there must be some corresponding products to align with these focus. How will Baidu carry out four key business?...

   Baidu, Anuual meeting, LBS,Baidu Cloud     2013-01-23 03:51:09

  Cool HTML5 matrix effect

Do you still remember the movie The Matrix? Do you still remember the cool matrix effect in that movie? How is that effect achieved? Shaun Dunne shared a piece of HTML5 code which displays a cool matrix effect. The matrix demo can be found here. Below is the code which he achieves this effect: with var s = window.screen; var width = q.width = s.width; var height = q.height = s.height; var letters = Array(256).join(1).split(''); var draw = function () { q.getContext('2d').fillStyle='rgba(0,0,...

   Matrix,HTML5     2013-08-14 08:03:34

  iPhone 5 first weekend sales over 5 million

Within 24 hours openning for pre-order, 2 million iPhone 5 have been ordered, Apple announces that  sales of iPhone 5 are over 5 million in 3 days on sale., in addition, iOS devices upgraded to iOS6 are around 100 million. Apple CEO Tim Cook says : Demand for iPhone 5 has been incredible and we are working hard to get an iPhone 5 into the hands of every customer who wants one as quickly as possible,While we have sold out of our initial supply, stores continue to receive iPhone 5 shipments ...

   iPhone5,,iOS6,sale,pre-order     2012-09-24 10:55:12

  Cool things you can do with iPhone

Nowadays smart phones have plenty of cool features you can get to know without reading the manuals. But do you know there are some useful but less well known features which can ease our life? In this post, we will share with you some cool features on iPhone. If you have an iPhone with, go and get a try. 1. Use Google Map as free GPS While traveling abroad, you can use Google Maps as a free GPS without an international data plan by making use of it's hidden offline maps feature.You can use this f...

   iPhone,Feature     2013-10-05 07:28:07

  Stream API in Java 8

Overview In this lesson on Stream API in Java, we will study how we can put Streams to use to write efficient and much more maintainable code. We will also write code with and without Streams so that we are able to compare the two versions. Before doing all this, we must know how to create a Stream and process it and that is what we will get started with. Introduction to Streams We will be starting with creating Streams. Let us get started with the Stream<T> API which enables us to play w...

   STREAM API,JAVA 8,DEVELOPMENT,TEAM     2018-01-30 00:14:46

  Different types of keystore in Java -- DKS

Domain KeyStore(DKS) is a keystore of keystore. It abstracts a collection of keystores that are presented as a single logical keystore. Itself is actually not a keystore. This new keystore type is introduced in Java 8. There is a new class DomainLoadStoreParameter which closely relates to DKS. To load different keystores into the single logical keystore, some configuration is needed. Here is the format of the configuration for grouping different keystores. domain [ ...] { keystore [ ....

   Java,keystore,DKS,tutorial     2015-01-20 02:27:27

  Google completes acquisition of Waze

Yesterday there was news about Google's acquisition of Waze with 1.3 billion US dollars. Today Google officially released news that they had completed the acquisition of Waze. However the price is not unveiled. Google said on its official blog : The Waze product development team will remain in Israel and operate separately for now. We’re excited about the prospect of enhancing Google Maps with some of the traffic update features provided by Waze and enhancing Waze with Google’s searc...

   Google,Waze,Acquisition     2013-06-11 13:02:42

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