The best push button phones. Java - Phones Java Operating System on the phone

History mobile communications Started with push-button phones. They enjoyed great demand for one and a half or two decades. And only in the late 2000s they began to crowd out smartphones with touch screen. But completely "button" has not disappeared so far. A large number of people who do not want to go to sensory control live in the world. It is for them today's rating has been created, which included the best phones with a physical keyboard.

It is important!

In our material it will be about ordinary mobile phones operating using proprietary firmware. In a separate selection you can get acquainted with the best push-button smartphones. They are equipped with a QWERTY keyboard, and Android is used as the operating system. As for the phones, you can only install Java applications on them, and T9 mode is used to enter text. Also on our site you can read about how smartphones differ from the phones where this topic is considered a little more. We can not not be noted and the fact that in our selection it will be about a variety of mobile phones. We are mentioned as the cheapest apparatus, usually used as spare, and more expensive models that have a slightly wider functionality. We are not forgotten by the topic of protected phones that can withstand even the most serious operational conditions.

Fly FF190.

Display:1.77 inches, 160 × 128 pixels
Battery capacity:1000 mAh.
Weight:71 g

Price: from 570 rubles.

One of the cheapest phones on the market got a lot of unnecessary bells and the only real plus. This model - This is a typical budget mobile phone that is created to simply call. However, for its money, FF190 offers customers with a 0.1 megapixel camera with video and photo recording feature (talk about quality with such a resolution over), Bluetooth 2.1 with A2DP support (improved sound transmission), reproducing not only music, but also rollers in formats 3GP, MP4, AVI.

All these chips with the exception can be improved audio via Bluetooth is clearly unnecessary. Hardly there is a person who wants to take something to actually useless the camera or watch the video on the screen of 1.7 inches. Of the advantages - for its price, the model received excellent autonomy and she has a flashlight.

Advantages:

Improved audio transmission wireless StandardMakes it possible to listen to music through a Bluetooth headset.
Excellent autonomy.
The presence of a flashlight.
Extremely low price.

Disadvantages:

A lot of unnecessary filling, which "weight" model - 71 grams, is not much, but against the background of the same price and size devices there is a difference.

BQ 2442 ONE L +

Display:2.4 inches, 320 × 240 pixels
Battery capacity:600 mAh.
Weight:75 g

Price: from 640 rubles.

After his return to the market, Nokia began to do not only interesting smartphones, but also ambiguous push-button phones. Multi-valued for the reason that there are many models, they are practically no difference between them, nor from competitors, but what is the most unpleasant - expensive. Of course, the company's name also affects the name of the company and, justice, the quality of Nokia is the best of everything that in principle can be bought in Russia among push-button devices. Nevertheless, curious specimens are found in the mobile phones of the Finnish company.

Model 8110 4G, as can be seen from the name, received not just support for the Internet, but even 4G speeds. It may seem that why is it necessary, because probably the stall filling, everything will slow down. But no, the brand engineers understood what they did and put quite seriously by the standards of push-button phones chipsets - Qualcomm MSM8905 with 2 cores of 1.1 MHz. It was complemented by the RAM 512 MB, which is quite good against the background of the traditional 32 MB in all other rating representatives and gave the buyer to a 4 GB drive.

This surprises do not end. There are Wi-Fi 802.11n and Bluetooth 4.1. As a cherry on the cake - a camera for 2 megapions. Naturally in 2019 it sounds ridiculous, but again - the phone is push-button. Most of the representatives of the segment are not and this. Do not forget that the model is a slider, that is, the buttons are hidden behind the retractable lid. There are two colors - yellow and black. The phone supports 2 sim. Included in his headphones are a pleasant trifle. Batteries enough for a couple of days of work.

This device was created for those buyers who, due to certain reasons, need a push-button device, but at the same time they want not only to call, but to photograph something and access the Internet.

Advantages:

Support Wi-Fi and 4G.
An interesting design of the housing in bright versions.
Excellent display.
Powerful iron for its segment.
Not bad by the standards of push-button phones camera.
4 GB of internal memory.

Disadvantages:

KAIOS - the smartphone operating system used is raw and there are many lags, the problem can be eliminated with updates.

Philips Xenium E181

Display:
Memory size: 32 MB
Battery capacity: 3100 mAh.
Weight: 123 g

Price: from 3 390 rubles.

Another phone from China Electronics Corporation with powerful battery. If you consider new push-button phones, then Philips Xenium E181 is certainly highlighted. When other devices work only one or two days, as well as modern smartphones, the product from CEC operates for four to five days. And if you leave it alone, without using at all, then the charge runs out only five months! Interestingly, the method of transmitting energy to other gadgets is implemented here. It turns out that this model can be used even as a portable battery. And here everything is in order with the characteristics. The device received FM radio and two slots for SIM cards. The built-in memory from the device is a bit, but no one will prevent you from downloading songs on the memory card. Everything else, the mobile phone is still not some record huge money!

Dignity

Highly cream battery.
Not bad display.
Not very big weight.
Two slots for SIM cards.
The ability to install the MicroSD card.

disadvantages

Very slow Internet.
The built-in memory is extremely small.
A terrible camera.
The functionality could be wider.

LG G360.

Display: 3 inches, TFT, 240 x 320 Points
Memory size: 20 MB
Battery capacity: 950 mAh.
Weight: 133 g

Price: from 4,000 rubles.

This clamshell is very beautiful, albeit very simple performed. It offers basic functionality - there is no access to the World Wide Web. On one of the parts of the device is enough big screen. However, his permission is far from the ideal - pixelization immediately strides. Against this background, there would be no amazing of the lack of support for MP3. But it is here, the songs must be downloaded to the memory card (cards are supported by up to 16 GB). The mobile phone has a 1.3 megapixel camera. According to the standards of 2017, this is ridiculous. But push-button mobile phones rarely get a better module. But the battery can be installed and more capacious - the battery existing here is enough for one or two days of autonomous work.

Dignity

Two slots for SIM cards.
MicroSD memory card is supported.
The presence of FM radio.
Loud speaker.
Relatively low weight.

disadvantages

Very high cost.
No Internet access.
Bad camera.
Low display resolution.

Excluded from the selection

Nokia 130.

Display: 1.8 inches, 128 × 160 pixels
Battery capacity: 1020 mAh.
Weight: 68 g

Price: from 1 890 rubles.

The simplest mobile phone from Nokia. It differs from competitors with minimal weight - in the pocket "tube" does not feel at all. The mobile phone has very modest sizes. However, this did not prevent the manufacturer additionally create a two-minute version of the phone. And here there is a microSD card slot. Without a memory card, the user can not do, as there is little free space for MP3 music and pictures here is critical.

Mounted here screen displays 65 thousand colors - this is a typical indicator for a simple mobile phone. Surprisingly, the creators introduced Bluetooth 3.0 support to this device, which makes it possible to use comfort wireless headset. There are FM radio here. The capacitance battery provides up to 13 hours of autonomous work in talk mode, which can be called a very good indicator. But there is no access to the Internet. This suggests that you will not be able to install additional Java applications or games.

Dignity

Easy development;
Loud communication works well;
MP3 format is supported;
Minimum weight;
Low cost;
Cream contact book;
A simple stereo headset;
Continuous work from one charge;
There is a two-minute option;
Bluetooth 3.0 is supported.

disadvantages

Its memory is very small;
You cannot install Java applications;
Tiny screen;
Quiet voice interlocutor.

Where can one buy: DNS, Granplus, M.Video and some online shopping

Nokia 3310 (2017)

Display: 2.4 inches, 240 × 320 pixels
Memory size: 16 MB
Battery capacity: 1200 mAh.
Weight: 79.6 g

Price: from 3 990 rubles.

The reincarnation of Nokia 3310 is a very controversial mobile phone. In fact, the device became popular only because of his name. Yes, this is a very thin mobile phone, and the information on its screen is well read even in a bright sunny day. But otherwise his use causes big questions. There is a camera, but its two-step-point permission does not cause any joyful feelings. In theory here you can install additional Java applications, but their list is strongly limited. But most of all consumers grieves the cost. The device with such a functionality should cost twice as cheaper!

Of course, there is a device and positive qualities. For example, Bluetooth 3.0 will ensure the connection of a wireless headset. The capacious battery is obliged to provide several days of work from one charge. Well, the memory card slot will help download great amount MP3 music. And here there is a FM radio.

Dignity

Very small thickness;
Not bad LCD display;
Support mp3 and FM radio;
Built in bluetooth technology 3.0;
Long work from one charge;
Included there is a headset;
You can insert a memory card.

disadvantages

Worthless chamber;
Terribly high cost;
Opportunities in the installation plan of applications are strongly limited;
Quiet speaker;
Highly simplified firmware.

MAXVI C11.

Display: 2.4 inches, TFT, 240 × 320 pixels
Memory size: 32 MB
Battery capacity: 800 mAh.
Weight: 80 g

Price: from 1,070 rubles.

This two-minute mobile phone exists at least in three versions. One painted in green, the other is in orange, the third is in the cherry. They no longer differ from each other. MAXVI C11 is one of those mobile phones who for some reason the camera is built. It has a resolution of 1.3 Mp, which is acceptable only if the photo is created for the contact book. Interestingly, the phone has access to a global web, but only after a 2G signal. And here is a built-in a memory card slot on which you can throw your favorite MP3 songs.

In general, Maxvi C11 is a very good phone for which we ask less than one and a half thousand rubles. For such money it is formed by the low capacity of the battery, and the minimum reserve of its own memory, and other shortcomings. But the presence of a flashlight plays him in a plus!

Dignity

Included there are headphones;
You can use the memory card;
Built in flashlight;
Bright colors of the case;
MP3 format is supported;
You can listen to FM radio;
Very low cost.

disadvantages

Its memory is very small;
Minimum firmware functional;
No support T9 when typing;
It is impossible to connect the headset (only headphones);
The kit may not be a USB cable.

Micromax x2400.

Display: 2.4 inches, TFT, 240 x 320 Points
Memory size: 75 KB
Battery capacity: 2800 mAh.
Weight: 89 g

Price: 1990 rub.

This is a very light mobile phone from the Indian manufacturer. We can say that this device is completely deprived of constant memory. But in fact it is not a problem, since there is support for memory cards to 8 GB. The main feature of the device can be considered its pretty design and ease of development. Buyers noted that the phone book works exactly here. Otherwise, it's not worth it for something special from such a cheap device. The camera here is the simplest, there is no point in its use. There is no Wi-Fi, therefore, in connection with which you can forget about the global web. You can only rejoice in the fact that the Micromax X2400 is not deprived of the Bluetooth module, so that no one forbits you to use the wireless headset. Also, it is impossible not to mark a very capacious battery, providing three or four days of autonomous work.

Dignity

Minimum weight;
Cream battery;
Not bad screen;
Two slots for SIM cards;
There is a memory card slot;
There is a FM radio;
Bluetooth support 3.0.

disadvantages

Terrible camera;
No support 3G and Wi-Fi;
The minimum amount of its memory.

Samsung Metro B350E.

Display: 2.4 inches, TFT, 240 x 320 Points
Memory size: 32 MB
Battery capacity: 1200 mAh.
Weight: 89 g

Price: 3990 rub.

Contrary to the opinion of many people, the South Korean company Samsung is still in addition to smartphones producing button mobile phones. Often they do not stand out with something special. These are just very easy devices that serve to make calls. It is this device that is Samsung Metro B350E. From wireless modules, only Bluetooth 2.1 is present here, providing communication with the headset. You can forget about entering the Internet, as there are no 3G support here. But but the mobile phone turned out very cheap! Oddly enough, South Koreans did not save on the camera. Her permission was 2 megapixel. This is enough for photographing the schedule of buses or something like. You can even take a picture of a friend to post his image in the phone book.

Dignity

There is a FM radio;
The memory cards of up to 16 GB are supported;
Minimum weight;
Relatively good display;
Two slots for SIM cards.

disadvantages

Weak battery;
No internet access;
Quite high cost.

BQ BQM-2408 Mexico

Display: 2.4 inches, TFT 240 x 320 Points
Memory size: 32 MB
Battery capacity: 800 mAh.
Weight: 78 g

Price: 1890 rub.

This is one of the easiest mobile phones Among those present in the market in this moment. If you want to get into your hands the device, which is almost not felt in hand, then BQM-2408 Mexico is the best choice. But at the same time you have to pay the fact that the mobile phone will require recharging almost every day. Another important feature is the ability to establish four SIM cards here. This allows you to use the services of all major Russian telecom operators! Otherwise, the device characteristics cause some sadness. In particular, there is a camera, but its permission does not exceed 0.3 Mp - it's surprising that such modules are still released. The Internet is offered to break through EDGE, and this indicates a low data rate.

Dignity

Minimum weight;
Relatively good screen;
Maps are supported by a capacity of up to 32 GB;
There is a FM radio;
Four slots for SIM cards.

disadvantages

The volume of built-in memory is not very large;
Minimum battery life;
There is no mode set T9 text;
Phone book well implemented.

BAQ BQM-2000 Baden - Baden

Display: 2 inches, TFT, 176 x 220 Points
Memory size: 32 MB
Battery capacity: 800 mAh.
Weight: 84 g

Price: 2690 rub.

This clamshell must mostly like older people. This is talking about this at least the presence on the SOS red button housing. Also, the device sounds very loud - not to hear the call is quite difficult. About your destination Phone speaks and lacking Internet access. If you want to download Baden - Baden on BQM-2000 Baden, you will have to use the computer. Additionally, the mobile phone has received a couple of customizable buttons. And here is auxiliary display. But only the date, time, battery level and signal level level are present on it. If you want to see the name of the caller, then the phone will have to disclose - only an icon indicates the receipt of an incoming call on the auxiliary screen.

Dignity

Form factor "clamshell";
Two screens;
Several additional keys;
There is a memory card slot;
The presence of the SOS button;
Minimum weight.

disadvantages

One slot for the SIM card;
Very poor functionality;
The external screen does not show the subscriber number.

Ruggear RG128 Mariner.

Display: 2.2 inches, TFT, 176 x 220 Points
Memory size: 65 KB
Battery capacity: 1400 mAh.
Weight: 127 g

Price: 4490 rub.

If you are interested in protected devices, then be sure to look at the nearest store Ruggear RG128 Mariner. This is not a smartphone, in connection with which the characteristics are not impressive. A 2.2-inch screen with a very modest resolution is used here, and the amount of memory makes it immediately stocking microSD card. But all this goes into the background when you see the package. There is a wired headset, literally saving in some situations. And two batteries are found in the box at once. One for 1400 mAh - he is more weighty, the other is 650 mAh - with him a mobile phone while getting into the water. Theoretically, this phone must withstand a variety of adversity. But the low cost makes itself felt. Some elements here are still very vulnerable. For example, the creators did not cover the screen with glass Gorilla Glass, in connection with which soon you will find scratches on it. Well, as for the technical characteristics, they are typical of the budget keypad.

Dignity

Protection against water, dust and shock;
Enough weight;
The presence of FM radio;
Bright color;
Two slots for SIM cards;
Availability of a memory card slot;
Two batteries complete.

disadvantages

Slow internet;
Minimum screen resolution;
Terrible camera;
There is practically no own memory.

The zoom.cnews survey of a certain number of respondents revealed an interesting pattern: most of users who own phones with support for Java technology do not use it. This fact seemed very strange to us, and unfair to useful technology. Therefore, we decided to tell you what Java is, and how can you make it serve yourself in a mobile phone.

How to make JAVA in a mobile phone serve you

What is java on the phone ways to download mobile

Make yourself

Let's start with the fact that you decided to acquire a mobile phone. Excellent idea, and we hope that she has gained material embodiment after a while. At first, everything is fine, your apparatus is the embodiment of the mind and beauty, and indeed the best. However, a month passes, the other, half a year, and you begin to notice that individual moments in your favorite are not realized in the best way. Well, let's say, an uncomfortable calculator, the organizer is scarce, the mail client is not, the standard WAP browser displays the HTML pages just awful, the installed games are already tired, etc. What to do?

The first thought is to buy a new phone. Not bad idea, but if she will come to your mind several times a month, then on new items may just not have enough money. According to our estimates, buying a new phone model, we have the right to count on at least a year and a half convenient operation. And let's see if I don't support the device with a sharply broke the device Java technology? If yes (about 90 percent of the currently produced phones), then you can assume that now you can add the necessary functionality yourself. Individuality is the first java featureallowing you to decide how you want to use your mobile phone.

What could it be? Yes, anything: new games, mail client Both web browser, reader books and spreadsheets, specialized calculator and scheduler, comfortable clocks and alarm clocks, educational and entertainment programs, etc. The spectrum of the possibilities of Java technology is limited only by the imagination of the creators, and they have, believe me, well, very violent. Of course, you should take into account the physical capabilities of the phone (the size of the display, the amount of memory, etc.), but this is quite natural, already mentioned iron after all, no one in the music center is trying to turn.

Creation of coffee lovers

A little story. Java's technology arose by no means on the island of the same name (and some think so), and in the depths of Sun Microsystems in 1991. The ideological inspirer Java is Patrick Notone, which is "tired of supporting hundreds of various program interfaces" (quote from Wikipedia). Together with his team, he managed to create a platform-independent programming language on which programs can be written for any processors and operating systems. Multi-platform is a Java postulate that implements the well-known principle "written once, works always." Feel what clone? It does not matter who the manufacturer of your phone, Java - Universal technology.

But still it should be noted that inside Java there are three main platforms (or versions), and the owners of mobile phones should only be interested in Java 2 Mobile Edition (J2ME). By and large, this is a set of configurations and modes targeting small user electronic devices. Not admitted in the subtleties of all these gradations, immediately say that in relation to mobile phones, Mobile Information Device Profile (MIDP) is used in the Connected Limited Device Configuration (CLDC) configuration. This is the basis of the implementation of J2ME in our case.

Just here, the specific possibilities of the Virtual Java Machine (JVM) are determined - the program itself, which is installed by the manufacturer in your phone and can process the Java application code (usually called Midlets). A small subtlety is a virtual machine one, and the technical capabilities of the phones are different. Therefore, the compatibility problem is still relevant, and a particular midlet can only be launched on a limited number of phone models (or even only one). So keep in mind. But manufacturers work on it, and I want to believe that someday we will deal with universal Midlets.

You should also mention the parallel existence of the two versions of Java MIDP, which actually define the functionality of the application: user interface, graphic and sound capabilities, networking, etc. The first appeared at the end of 2000 and today is supported by a majority telephone. As for Java MIDP 2.0, it is announced at the end of 2002, but began to be used by manufacturers only in models of the 2004-05 models. So you can only meet it in fairly new models of phones.

About Midlets and Phones

What is Midlet? Usually a Java application is a set of two files: a descriptor or pointer with the extension of the JAD and the JAR archive itself. As for the descriptor, today the presence of this file is not mandatory. The fact is that it was originally assumed to load midlelets only from the network (all methods of downloading below), so the user and was forced to run this file on his phone, which contained information about the application, its size, installer settings, and, most importantly, A link to the jar file (you can verify yourself, the JAD file has a text format). However, some phones have the ability to download the application directly, that is, simply rewriting the file, which reduced the utility of the descriptor to zero.

As for modern models, this operation is standard for them, so that one JAR file is enough to download the Midlet. By its structure, this file is an archive, and files included in its composition can be easily seen on a computer by any archiver (ZIP, RAR, etc.). Note that sometimes, the application may also include other files, most often these are additional databases, but it is rarely found.

We now turn to the phone. In order to upload a midelet into it, the device first should have some memory for normal application loading. The size of the Java application can extend from units to hundreds of kilobytes, which causes the relevant telephone requirements. Well, we think about modern models, the amount of memory of which is calculated by megabytes, it is not worth talking, but with the "old people" will have to tinker. You understand yourself, having the amount of memory at 100-200 Kb, you will have to move a little, that is, remove all unnecessary (first of all it concerns pictures and melodies). In principle, this is a serious problem only for business applications that need constantly, as for the games, everything is simple here. They downloaded the game, widowed, erased, recorded the following, etc., until you get bored.

"Red Eye", "Blue Tooth" and Other

No, this is not an excursion to anomalous anatomy, it will be about ways to download moldlets to the phone. In our opinion, about the presence of something of the following listed in the phone should be worried when buying a phone so that it was not a shame. As you understand, you can choose only if there is from anything. Most available way - This is the use of a DATA cable. We connect the interface connector of the phone with the COM or USB computer connector (oh, and it is necessary for you, if the computer is under the table, and all connectors on the rear wall). Everything is simple and securely, except that you can complain to the very presence of cable, that is, wires.

Whether business wireless communications. Once configured everything, as you need, and then chase there and a program. Please note here you can use not only the "Computer-phone" chain, but also a "phone-phone", which gives a huge plus. Had seen interesting application Have a friend, and immediately downloaded him. Two options are possible: infrared connection and bluetooth. To use IRDA, many users relate negatively, and in vain. Despite the "antiquity" of this method and the need to perform a number of conditions (the distance between IR transceivers is 10-20 cm, finding them on a straight line, etc.), it is quite suitable for periodic loading. If you are close to Java, then the perfect way is Bluetooth. Yes, of course, for the first time you will have to "make friends" among themselves phones, or a phone with a computer (spiring procedures, authentication, etc.), but then the real paradise. Within a radius of 10 meters, you can download and download applications without any wires.

One more quite affordable in lately The download option of Java applications was once thought as the main thing - this is "injection through the air", that is, using the operator's network. Today, almost all operators support WAP and GPRS, and even wise on EDGE. In addition, it should not be underestimated, because in the absence of the above injection methods, the support for the Java telephone means the mandatory availability of a WAP browser, at least we did not find out of this (it is quite logical, otherwise why Java is needed). The display process explanation does not require, score the address in the browser bar from where the application will be downloaded and all. Also note the existence of the so-called "WAP exchangers" where you can on an hour or other reset the application, for example, from a computer, and then "pick up" it from the phone.

Something about softe

In principle, the software for the computer has an indirect attitude towards our topic, but since the "Computer-phone" chain is relevant for many, they are driving a bit and on it. We understand, it is clear that it is impossible to combine two devices with each other without the appropriate software. And if we want to download anything else to the phone, you must definitely need specialized software. The best way, in our opinion, is the use of a software package from the phone manufacturer, which often comes with a phone, in extreme cases, you can download it from the Internet (Nokia PC Suite, Siemens Data Suite, Starfish TrueSync et al.). The use of third-party packages (for example, Oxygen Phone Manager) justified only in some cases, for example, the functions you need in the official software are missing, or the computer is used to connect to several phones of various manufacturers.

We go Search Midlet

Actually, speaking, create your own application on J2ME is quite real. SDK software (Software Development Kit) is available free of charge, the licensing is absent, so if you wish, you can try. However, we will not deepen into the deburs of programming, and try to find ready-made mideleta, the benefit of them is created abound. As we mentioned the fastest and free way - it is to take your favorite application from a friend. But still let's turn to third-party resources.

First of all, it is worth asking what your operator can offer. Mobile content proposal has become a significant source of income for them, so today only lazy does not offer Java applications. Unfortunately, 99% of Midlets are games, but it is impossible to resist this, the market is the market, which users want, then the operator offers. Almost always to download a WAP connection (sometimes through GPRS), so you need to bother in advance about the revitalization of this service.

If your creative nature does not accept such a simple loading mechanism "chose-paid-received," and you are in freaks with a WAP-browser of the phone, you can go into your own swimming. That's what we managed to achieve in ten minutes. When typing in the browser, the address of the Russian-speaking search engine wapl.ru (http://wapl.ru) The cherished term "java", we received a huge number of references to the relevant resources, as much as 438 pieces. Having shifted a few first pages with references, we managed to find a couple of good sites with applications .... However, we will stop the remaining path we suggest to do you yourself.

The phone, of course, is good thing, but still we think that the optimal tool for finding midlets on the Internet is desktop computer. A familiar interface and convenient information entry devices allow you to read the description of the application in detail, see screenshots and determine its necessity. We will not bring the addresses of numerous sites with applications, we will have enough, we will mention only the most popular - Midlet.org (http://midlet.org/), containing about 500 applications. If it is interesting, then here is the "high-quality" composition of the composed for downloading Middlets: 30% - utilities, 6% - applications for working with the Internet, 8% - graphic programs, 3% - Utilities for developers, everything else - games.

Her Majesty java.

In conclusion, we want to recall once again that Java technology today is the most affordable and efficient by expanding the functionality of a mobile phone. And then the phone will be: an assistant in affairs or entertainment terminal, entirely depends on you. The number of existing applications is measured by thousands, and you have the right to choose what is needed. Better and look no need. We hope that we were able to convince you. Not? Then we go to you…

There is no point in telling how the business associated with cell phones has increased in recent years. Technical progress in the field of PC or other equipment, of course, covers everything that is somehow connected with electronics. So, for example, I did not bypass already, the world-famous and modern Java program language, the above mentioned mobile phones. To date, tens of thousands of cell phones with Java support are sold daily. That is, the device is not distant when the device will be lying in your pocket, providing not only an excellent connection, but also being a small, say, a personal computer that is not inferior to pocket computers already available on the market. And, since. It is waiting for us ahead, you will return today and talk about those models (with Java support) that you can buy right now.

What is Java? As already noted, this is a language that provides independence by from hardware and operating platforms. Java was created in the laboratories of Sun Microsystems James Gosling. Using the J2ME (Java 2 Micro Edition) platform, which includes a Java program development tools and a "java machine" (operating system), in which, by means of a microprocessor built-in in cellular telephone. They will be performed. Programs are called "Midlets" (Midlets, MID - from Mobile Information Device Application), which can be installed in a mobile phone via a PC Data cable, infrared port or Bluetooth connection or installed from WEB servers via WAP. The number of applications for phones, due to the fact that the programmers owning Java are quite a lot, are constantly increasing. In the network there are many sites containing similar firmware, for example, you can call the Javamobiles.com website where there are free midelets, including: Games, Network Utilities, Applications, Graphics Tools, Demos and other entertaining scripts. A large number of services that use Java features providing free or commercial applications such as chats, programs for obtaining and viewing stock exchange information and business applications related, for example, with stock quotes, as well as for work and information sharing . Therefore, in the presence of a cell phone, with J2ME support, you can replenish it with a variety of utilities. But we turn directly to the devices. who give the user this, you agree, a fairly pleasant opportunity. J2ME is already widely used in Motorola, Nokia, Siemens, NEC, and many other firms, more progressive development - Mobile Information Device Profile (MIDP), today finds widespread use in pocket PCs and smart backgrounds.

Today, many mobile phone models with Java 2 Micro Edition support are really available. Below you have the opportunity to get acquainted with these products closer.

Siemens SL45I.

In June 2001 Singapore at the Communicasia 2001 exhibition, Siemens presented, almost similar to the older SL45 model, its new SL45i brainchild. It should be noted that these phones do not differ anything, with the exception of the presence in the last support of Java applications that can be executed on this unit.

The first thing that rushes into the eyes, considering the phone is a seven-term digital display that perfectly clearly provides animated images of all the games provided in this model, their colorfulness and in addition functions such as vibrating alerts and games that can be easily supported by Java applications Replaced with new ones. But this is only the first impression.

Also, this phone provides selective initialization of application loading via SMS function. Freedom of choosing actions is also pleased too, for example, you can first view the program, send to a friend and after that, at the request of the user, to put it in the list of other programs of your device.

Operating SL45i, you immediately feel the speed and efficiency of triggering functions when working with applications, such as their replacement, recording, reproduction, due to the fact that the amount of memory in this model is significantly increased due to the Multimediacard (MMC) card. The presence of MP3 player allows you to distracted by the user from the bustle of the world of this and listen to your favorite music, although it should be noted that it requires most of the 32-MB resource MMC. It has already been written about the speed of this model, which entails saving time and, accordingly, money when using the J2ME function when reading or responding to a message. Even before connecting to the network via WAP 1.1 to send a message, you first make it in offline modethat, of course. Significantly reduces costs when working with SL45i. For about 5 hours, the user can use such a function as voice messaging and synchronization with a PC, the benefit of this phone allows shift Map Multimediacard (MMC) on 32 MB to record a sufficiently large number of files.

Also, this unit allows you to install, by connecting to the Internet or PC of various kinds of screensaver, the screen of the device, a wide variety of ringtones and graphic objects is welded with its dimensions. All this, of course, emphasizes not only the individuality of the user, but also gives a real opportunity to show his fantasy for the purpose of pleasant and useful work with Siemens SL45i.

The Java 2 Micro Edition (J2ME) platform was designed for the consumer market of devices with disabilities and processor such as: cell phones, pagers, smart cards, organizers and minicomputers. J2ME allows you to run Java on resource-limited computing devices. For these goals, J2ME adapts an existing Java technology. Consider two key points J2ME: configuration and profiles.

Configuration.

The configuration determines the J2ME execution environment. It includes a virtual machine limited compared to standard VM and a set of basic classes, mainly borrowed from J2SE. Currently identified 2 configurations: Connected Limited Device Configuration, CLDC Configuration and Configuration Configuration (Connected Device Configuration, CDC). The first configuration is oriented on a micro device equipped with 16- or 32-bit processors with a minimum memory of about 128 KB. The heart of the J2ME CLDC is the K Virtual Machine virtual machine (KVM) specifically designed for network devices with a small amount of memory and limited resources. The second J2ME, CDC configuration is focused on more complex electronic and built-in devices, such as smart communicators, complex "intelligent" pagers, personal digital assistants (PDA) and interactive digital television consoles. As a rule, such devices are equipped with a 32-bit microprocessor / controller and are equipped with more than 2 MB of memory used to store the virtual machine and libraries. CDC works with Virtual Machine virtual machine (CVM). CDC includes all classes from CLDC and even more classes from J2SE. The main difference between the CDC and CLDC is that the CDC VM supports all J2SE VM features including Native Programming Interfaces

Profile.

The profile expands the configuration by adding specific classes to the set of basic classes defined in the configuration. In other words, the profile provides the necessary functionality that is absent in the main configuration. It can be a user interface, storage mechanism, etc. In addition to MIDP profile, there are other profiles.

Foundation Profile - adds a set of classes from J2SE to CDC but does not enter user interface. This profile is used to build other profiles on it.JSR-46

Personal Basic Profile - Provides Java API for devices requiring network access and graphic presentation. This profile is suitable for interactive television and contains an API to support Multimedia Home Platform. (JSR129)

Personal Profile - Provides Java API for devices requiring reliable network access built on Personal Basic Profile and Foundation Profile (JSR62)

Figure 1. J2ME architecture.

CLDC (configurations of communication devices with limited resources)

CLDC is the result java works Community Process (JSP) of the JSR-30 expert group to which the following companies were compiled:

America Online.

Ericsson.

Fujitsu.

Matsushita.

Mitsubishi.

Motorola.

Nokia.

NTT Docomo.

Oracle

Palm Computing

Samsung

Sharp.

Siemens.

Sun Microsystems.

Symbian.

CLDC technology is used to settle various profiles. The purpose of this technology to determine the standard of using Java on devices with limited resources.

160-500 KB Memory Available to Java Platform

16-32 Bit processor

low energy consumption

network connection 9600 BPS or less.

Below are aspects that fall under the "jurisdiction" CLDC:

The following things are not included in the CLDC Consideration area: (as a rule, they are determined by profiles.)

User interface

Processing events

Life cycle applications

User interaction and applications

Java language and virtual machine KVM

The main target for JVM supporting CLDC is compatible with Java Language Specification as much as possible. With the exception of the differences below, JVM which supports CLDC, compatible with Java Language Specification.

No support for Floating Point. This is due to the fact that in devices with limited resources there is no support for Floating Point. Support on the program level would be too expensive.
CLDC supports Exception mechanismHowever, his arsenal is limited. This is due to two reasons:
- Recovery after errors are quite specific for each device. In addition, many devices simply reboot after some of their mistakes. The application cannot take care of such errors.
- The complete implementation of the mechanism is too expensive pleasure for micro devices.

KVM.

No support for Floating Point. This is due to the fact that in devices with limited resources there is no support for Floating Point. Support on the program level would be too expensive. In JVM which supports CLDC there are no byteskodes associated with Float and Double types.
KVM does not implement Java Native Interface (JNI). Support JNI was rejected for two reasons.
- Restrictions imposed by the Security model CLDC. (This model prohibits using Native Calls.)
- The full implementation of JNI was recognized too expensive for devices with limited resources.
KVM does not allow you to create your Class Loader. These are restrictions imposed by the Security model.
KVM does not support Reflection mechanism.Java applications cannot inspect classes, objects, methods, fields, threads performed by stacks in virtual Machine. As a result, serialization, JVMDI (PROFILER INTERFACE), JVMPI (Profiler Interface) and other J2SE technologies based on the reflection mechanism are not available in CLDC.
KVM implements multithreading, but does not support Thread GROUP and Daemon Thread. Operations such as starting and stopping can only be applied over a separate thread.
There is no Finalize () method and there is no weak references. This requirement is associated with the need to simplify the mechanism of garbage collection.
Limited Error Handling Mechanism compared to J2SE.
Transworking.

CLDC library.

CLDC libraries can be divided into two categories:

The first category includes classes inherited from J2SE.
In the second classes that enters the CLDC.

Classes belonging to the first category are in Java.Lang packages. *, Java.util. *, And java.io. *. These classes are derived from Java 2 Standard Edition version 1.3. These classes are identical to the relevant J2SE classes. Semantics of classes and their methods will not change. Any public or protected methods that are not available in J2SE will not be added to the classes.

System classes.

These classes are internally associated with a virtual machine. Some applications Java require classes data. For example, J2SE Java Compiler (Javac) generating code, requires certain String and StringBuffer classes functions. java.lang.Object
java.lang.class.
java.lang.runtime.
java.lang.system
java.lang.Thread.
java.lang.runnable (Interface)
java.lang.string
java.lang.stringbuffer.
java.lang.throwable

Presentation classes.

Each of these classes are a subset of the corresponding classes from J2SE.

java.lang.Boolean.
Java.Lang.Byte.
java.lang.short
java.lang.integer
java.lang.long
java.lang.character.

Collection classes.

java.util.vector
java.util.stack
java.util.hashtable
java.util.enumeration (Interface)

Output classes.

java.io.inputstream
java.io.outputstream
java.io.bytearrayInputstream
java.io.bytearrayoutputstream
java.io.datainput (Interface)
java.io.dataoutput (interface)
java.io.datainputstream
java.io.dataoutputstream
java.io.Reader.
java.io.writer.
java.io.InputStreamReader.
java.io.outputstreamwriter.
java.io.printstream

Classes Reader, Writer, InputStreamReader and InputStreamwriter provide interpartine support.

The mechanism of their work is the same as in J2SE. The last two classes have exactly the same constructors as in J2SE.

new InputStreamReader (InputStream IS); New InputStreamReader (InputStream IS, String Name); New OutputStreamWriter (OutputStream OS); New OutputStreamWriter (OutputStream OS, String Name);

In cases where the String parameter is present, the specified Character Encoding is used, otherwise the Character Encoding is used, the name of which is contained in the variable microedition.encoding. If the converter is not available, unsupporteddencodingException is thrown out.

It should be noted that CLDC does not support localization. This suggests that all solutions related to the formatting of the date of time, etc. find out outside the CLDC.

Calendar and time.
CLDC includes a small subset of standard J2SE classes: java.util.calendar, java.util.date, and java.util.timezone. By default, one time zone is supported.

java.util.calendar
java.util.date.
java.util.timezone

"Auxiliary" classes.
java.util.random class contains a simple generator of random numbers.
Java.Lang.math has in its set ABS, MAX and MIN methods for int and long types.

Exception & Error.
java.lang.exception
java.lang.classNotFoundException
java.lang.illegalaccessException
java.lang.instantiationException
java.lang.interruptedException
java.lang.RuntimeException
java.lang.arithmeticexception
java.lang.ArraystoreException
java.lang.classcastexception
java.lang.illegAlarGumentException
java.lang.illegalthreadstateException
java.lang.numberFormateException
java.lang.illegalMonitorsTateException
java.lang.IndexOUTOFBOUNDSException
java.lang.ArrayIndExOUTOFBOUNDSException
java.lang.stringIndexOUTOFBOUNDSException
java.lang.negativeArraySizeException
java.lang.nullPointerexception
java.lang.securityException
java.util.EmptystackException
java.util.nosuchelementException
java.io.eofexception
java.io.ioException
java.io.interruptedioException
java.io.unsupportedencodingException
java.io.utfdataformatException

java.lang.error
java.lang.virtualmachineerror
java.lang.outofmemorryerror

Propety.
The CLDC does not have a Java.util.Properties class. However, Property can be accessible using the static System.GetProperty method (String Key). The minimum Properties set provided by CLDC is next.

microedition.encoding
microedition.platform
Microedition.configuration.
microedition.profiles.

Classes belonging to the second category are in javax.microodition packages. *. The javax.microodition.io package enters a new network support mechanism.

CLDC Connection Framework.

java.io. * and java.net. * J2SE packets are not suitable for micro devices with their limited resources. Therefore, a new javax.microeditiony package was developed.

This package has only one class: Connector, 8 interfaces and ConnectionNotFoundException.

Class Connector is the heart of the Connection Framework, it has a number of static methods to receive the connection of the object. If the operation is successful, the method returns an object that implements the connection to the interface otherwise misses the iOexception. Figure 2 shows the hierarchy of interfaces.

Figure 2. Interface hierarchy

Object implemented Connection. The interface can be obtained using the CONNECTOR class, as mentioned above. Interface Connection. It has a single method close.. This method Closes network connection.

InputConnection The interface "represents the device" from which you can read the data. Methods openInPutStream and openDataInputstream Returns a stream for reading.
OutputConnection. The interface "represents the device" in which you can write data. Methods openOutputstream and openDataoutputstream Return the flow to record.
StreamConnection. Interface combines IntputConnection and OutputConnection..
ContentConnection. Subinterface StreamConnection..
StreamConnectionNotified. Waiting for the connection will be installed. Method acceptandopen () Returns StreamConnection. an object.
DataGramConnection. The interface determines the datagram connection.
ConnectionNotFoundException Throwing out when the connection cannot be rejected.

Connector.

The String Open Class Connector method has the following format. "Protocol: Address; Parameters".

Here are some examples:

HTTP Connection Connector.Open ("http://java.sun.com/developer"); Socket Sockets: Connector.open ("socket: //129.144.111.222: 9000"); Datagram Connection Connector.Open ("Datagram: // Address: Port #"); COMMUNICATE WITH A PORT CONNECTOR.OPEN ("COMM: 0; BAUDRATE \u003d 9600"); Open Files.
Connector.Open ("File: /myFile.txt"); Network File Systems: Connector.open ("nfs: /foo.com/foo.dat");

Security.

One of the huge benefits of Java is the dynamic application of applications via the network, to the client using a reliable Security mechanism. The implementation of this mechanism in the J2SE exceeds the capabilities of the available memory budget for JVM supporting CLDC. For CLDC, a different mechanism was developed that can be divided into two levels: the level of the virtual machine and the level of the application.

Virtual machine level - It implies that the launched application in VM should not have the ability to hurt the device in any way. This requirement should provide Java Classfile Verifier, which must ensure that the loadable bytecode does not contain references to invalid memory areas or memory located outside the Java Heap. Verifier must reject the download of such classes.

Application level. Verifier is not a salvation from all the troubles, it only checks the Baitcode on the "Environment" but it cannot guarantee that the downloaded application will not harm the device. The J2SE SecurityManager provides control over that the application cannot, it is not authorized to refer to the file system, establish a connection, etc .. but the implementation of such control is impossible for mini devices with their restrictions.

In JVM supporting CLDC implemented Sandbox Security model. This model assumes that the application must be performed in a limited environment in which the application can only have access to the APIs that are defined in configurations, profiles and linensed classes.

More accurate Sandbox model means:

Downloadable java class files must be verified
The application can only access the APIs that are defined in configurations, profiles and linensed classes.
Application download can only be performed by the Native virtual machine code and cannot be made by Class Loader by a specific user. Therefore, the CLDC cannot create your Class Loader.
The application cannot download a Native library, the application cannot have access to Native functions that are available virtual machine and have access to Native libers that are not Java libraries provided by CLDC, profiles or linensed classes.

In addition, profiles can add their limitations to the foregoing.

MIDP.

MOBILE INFORMATION DEVICE PROFILE Expands CLDC. By adding three new packages: puts out the requirements for installing Middlets, which should be contained in Midlet Suites adds several classes to already available packages defined in CLDC.:

javax.microedition.io. To java.io package adds an HttpConnection interface.
java.lang.Java.lang Package Adds IllegalStateException (Java.Lang.illegalStateException).
java.util Adds functionality that allows applications to create timers. For these purposes, the java.util.timer and java.util.timertask classes from J2SE were added.

What is java?

For starters, let's figure out what manufacturers are offered under the java brand name.

So, Java is an object programming language that has replaced ADA. It was created in the early 90s in the Pentagon for the needs of the military industry. A program written in Java is compiled into a special byte - code that is performed on a virtual java-machine. In fact, Java - the car is not at all a car, but a program that has many implementations (computers of various architectures running through all kinds of operating systems). Once written and transformed into bytes, the program can be successfully executed on any java - machine.

No one could assume that for some 2nd - 3 years Java will receive such a wide application: from the creation of "smart" Web-pages (Apple Technology) before the development of giant banking systems. Separately, the direction of the so-called built-in systems and real-time systems is allocated: under the control of Java, the washing machines, refrigerators, televisions, telephones and even wristwatch have been operating.

Last year, the second appeared java version, the so-called Java 2, which can be viewed as a full platform, that is, the totality of the machine and the operating system. Today there are three implementations of the Java 2 platform: Standard Edition (for ordinary applications and systems), Enterprise Edition (for application application applications and large clients - server Systems) And Micro Edition (for small devices, such as cell phones, PDA, organizers and smart cards with an intelligent chip). We are under the word "Java" we will mean the platform and technology Java 2 Micro Edition, abbreviated J2ME.

So, if the phone supports Java, it means that it can execute programs written in the Java language created for the J2ME platform. How do programs come to the phone? All Java - phones are equipped with interfaces for connecting to a personal computer. From the point of view of the computer, file system The phone looks like a simple folder where you can copy the program for further execution.

From the point of view of the phone, the copied program turns into a menu item.

The programs can be downloaded and installed directly from the mobile phone, via WAP, and for smartphones and communicators - through www.

Java - phones

On May 16, 2002, a joint press was held in London - the Java Region Leaders' Conference - Siemens AG and Nokia Corp phones, which stated that the audience of Java users - phones gSM standard Makes more than 1 million people. I intentionally used the phrase "java - phone", since all new models of phones and smartphones (both Nokia and Siemens) support Java or Symbian OS, the Linux family system with built-in Java support.

A few months ago, there were about 2 dozen such phones in the world, mainly in Japan and the United States, IDEN and CDMA standards. And only 3 models - for GSM: Siemens SL45I (quite good, but dear because of the built-in MP3 - Player) and two Nokia, namely 3410 and Communicator 9210. Now Java supports more than 100 phones, of which about a third of the device GSM standard. Some of them have already appeared in free sale, the rest are still announced.

Consider a Read more Java market - telephones available today to Russian users. (All conclusions below are based on personal experience The author of the article, which is already the year for the Software Developer Developer team for Java - Phones in ZAO "Lanit - Terkk", St. Petersburg.)

Siemens SL45i and Nokia 3410

Siemens SL45I - the first cellular Java - GSM standard phone. And quite expensive - because of the built-in MP3 - Player. 32 MB data warehouse can be expanded to 64 MB. The amount of memory (heap size) is about 130 kb. Thanks to the large amount of memory and wide screen (101x80) until the last moment, it was an ideal platform for both serious business applications and games, despite the black and white graphics. Today it is obsolete and displaced by newer and cheap devices, as it does not support GPRS.

Nokia 3410 appeared as a response Nokia on Siemens SL45i. Technically, they are similar, but from the point of view of the possibilities of software development, Siemens wins, and significantly.

Siemens M50 and Nokia 6310i

Unlike previous modelSiemens M50 supports GPRS. The amount of data warehouse is 200 KB. This is enough to install approximately 6 games or 2 serious business applications. M50 is significantly cheaper than the predecessor: its price is only $ 160 - 180. The developers believe that the phone will gain wide popularity among the population. In our opinion, this is a good gaming platform, suitable for small business applications. It is noteworthy that Siemens M50 has a built-in ICQ - client.

Nokia 6310i also supports GPRS. This is a more expensive model capable of functioning without recharging to 17 (!) Day. From the implementation point of view of Java applications, the device is approaching Siemens M50, but the phones are not compatible, which complicates the development of effective programs for both platforms.

Most of the programs offered today manufacturers for these phones make up games. Although there are personal business applications, such as E-mail clients and calendars with advanced features.

Nokia 9200 family

In Russia, the Communicator 9210 is known, a little less - its modification of 9210i. latest model - 9290. All of them, in essence, are pocket computers with a normal keyboard, display, Linux - similar Symbian 4.0 operating system. The devices are very expensive, large and heavy for use as a simple phone or platform for games. For them, a large number of both Java applications and specialized programs for OS Symbian are developed. These are mainly systems management Web. - nodes, warehouses, shops. Such systems are used in Russia.

As for the Games, any game for J2ME or Java can be installed on the communicator - a game using the Nokia expansion. Separately, I want to highlight the game Snowboarding, developed by Nokia Corp.

Siemens SX45 and Nokia 7650

In essence, these are full computers equipped with color screens and running the Symbian 6.0 operating system. The characteristic feature of these devices is a simplified input interface: unlike communicators, they have an ordinary telephone keyboard extended by additional navigation tools.

So far, smartphones are quite expensive (for example, Nokia 7650 costs about $ 600), but this is the most promising direction in the mobile industry. On smartphones you can implement complex customers for complex business systems up to the enterprise management systems. And they are really in demand now.

Java for the user

The essential part of the applications downloaded to Java are telephones around the world, make up games. What is the secret of such popularity? The fact is that with WAP or WWW, the user can choose the game to taste and install it on your phone, practically without changing your location. Network games are particularly popular, allowing fun in the virtual world (chess, football, card games, there is even a mobile DO).

Mobile game production has not yet received a wide scope. On the one hand, this is due to the lack of large number Cheap mobile devices with Java support, on the other hand, the development and adaptation of mobile games has no analogues in other areas of the Gaming Industry. Nevertheless, according to specialists of Nokia and Sun Microsystems, production and electronic trading Java games for phones (the so-called Midlet "Ami) will soon acquire a global scale. Already in Europe there are companies that are based on the MIDlet trade" AMI. An example of this can be the Finnish company Mr.Goodliving (www.mrgoodliving.com).

In addition, on the Internet you can find a lot of free Java - games (for example, at www.microjava.com).

Unfortunately, Russia is still lagging behind Europe and America, but the situation will change soon. Representatives of the largest Russian cellular provider told us in a private conversation that if 2002 was the year of SMS - entertainment, the next one will become the year of mobile games.

Java for business

Creating business applications for Java phones is considered a very promising direction in the software industry.

Classical Business - The system consists of a Web server, an application server on which the business layer works, which interacts with the DBMS. The Web server provides the work of the WWW - interface, and also organizes communication with client applications. The client application can be installed on a computer in the office or on a cell phone and be MiDlet. As already mentioned, such applications have already been distributed in Russia.

The scheme of operation of such a system is quite complex, moreover, for each situation, it is developed on a new one, so we will consider the process on the example of a non-existent order management system of the non-existent company Pizzafast.

So, suppose that Pizzafast has an orders based on WWW. Access to the system occurs through the Web - the company's website where the user can register and order pizza with specified parameters With delivery by specified address. In addition, you can go to the system and via WAP (actually, WAP - pages are located on the same Web server). In addition, you can download special program For a cell phone that supports Java, which allows you to make an order from anywhere where there is cellularAnd much cheaper and more convenient than WAP. With a special desire, the user will be able to download the program and via WAP, spending just a couple of minutes to not overpay.

The program allows you to get a menu, select an order, pay for a credit card order or select payment mode at the time of delivery, as well as specify the time and address to which pizza should be delivered. Frequently used orders can be saved in the phone to repeat them without re-input. Permanent customers registered in the system receive discounts and, if desired, weekly distribution "All about pizza" and "News Pizzafast" in SMS format.

Each courier has a cell phone to which orders management system is installed. He gets from the server a list of orders belonging to its area. Having received a pizza in the nearest branch of Pizzafast, the courier marks the order as active to coordinate its actions with the couriers of the area with him. Having delivered the order, he notes him as executed. If in some area the couriers do not cope, the dispatcher in the main office can pass part of orders to couriers from the neighboring area.

Managers at any minute can get statistics from their phones to which the monitoring system is installed, also decorated as MIDlet.

The Director General once a day receives the SMS "ku, in which the amount of day profit is indicated. If desired, it can obtain data on the demand for one pizza at a given time interval. For this purpose, the" Director "MIDlet is installed on his phone.

It all looks pretty funny. But if the seller of pizza seems like a fairy tale, then the manager and software developer is clear that the future is worth it. What will be this future, it is necessary to decide today to keep up with more prosecable competitors.