Java operating system linux

Установка Java в Linux

В этой статье речь пойдёт о проприетарной версии Java. Часто происходят ситуации, когда пользователь пытается открыть какую-либо программу на Java, а она либо вообще не запускается, либо пытается это сделать с помощью OpenJDK (Java Development Kit). Но вместо результата вы получаете кучу ошибок (как например с Minecraft). В данных ситуациях вам, скорее всего, поможет установка Java от Oracle.

Я вам расскажу, как установить JRE (Java Runtime Environment) и JDK (Java Development Kit) 8 версии на такие дистрибутивы, как Ubuntu, CentOS и Arch, а также как выбрать нужную среду по умолчанию.

Чем отличается JDK от JRE

• JRE — Java Runtime Environment — это среда выполнения Java. Предназначена для обычного использования. Позволяет запускать приложения, написанные на языке Java.
• JDK— Java Development Kit — стандартная версия платформы Java, предназначенная для разработки. Это специальный пакет разработчика, в который входят документация, различные утилиты, компилятор, библиотеки классов, а также сама JRE.

Установка Java в Linux своими руками

Скачать архив с необходимой вам версией вы можете с официального сайта. Далее вам надо перенести его в желаемую директорию и распаковать. Рекомендую /opt/java, далее она и будет использоваться. Сделайте это, используя следующие команды:

sudo tar -xzf /opt/java/jre*.tar.gz

Где «*» — версия Java.

Загрузите архив со средствами разработчки с официального сайта компании Oracle. Также перенесите его в желаемую директорию и распакуйте:

sudo tar -xzf /opt/java/jdk*.tar.gz

Установка Java в Ubuntu

JRE и JDK

Для установки проприетарной Oracle Java вам необходимо добавить репозиторий, обновить индексы пакетов и установить Java. В Ubuntu, начиная с 18 релиза, это делается автоматически после добавления репозитория.

Внимание! Будут установлены как JRE, так и JDK. Сначала добавим репозиторий и обновим списки пакетов:

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update

В процессе установки необходимо будет принять лицензионное соглашение:

sudo apt-get install oracle-java8-installer

Установка Java в ArchLinux

В официальных репозиториях есть только OpenJDK. Поэтому придётся воспользоваться пакетом из AUR(вы можете, конечно, руками установить Java от Oracle, но AUR проще). Установка производится всего одной командой:

JDK так же можно установить, используя AUR. Просто выполните команду:

Установка Java в CentOS

Для RHEL, Fedora, Cent OS, OpenSUSE есть официальный RPM-пакет, который вы можете скачать с официального сайта. Чтобы установить пакет из терминала, воспользуйтесь этой командой:

sudo rpm -i /путь/к/файлу/jre-*.rpm

где «*» — версия Java. Или же примените любую графическую утилиту.

Средства для разработчика вы можете скачать на сайте Oracle, ссылка на который есть в верху статьи. Для установки из терминала, используйте команду:

Где «*» — версия Java. «

» — указывает, что путь начинается.

Выбор версии Java

Ubuntu

Для переключения на 8 версию Java используйте следующую команду:

sudo update-java-alternatives -s java-8-oracle

Чтобы автоматически установить переменные среды, воспользуйтесь командой:

sudo apt-get install oracle-java8-set-default

Или же вы можете установить альтернативы сами. Делается это с помощью следующих команд:

sudo update-alternatives —install /usr/bin/java java / usr / lib / jvm / java-8-oracle/bin/java 1

sudo update-alternatives —install / usr / bin / javaс javaс / usr / lib / jvm / java-8-oracle / bin / javaс 1

sudo update-alternatives —install / usr / bin / javaws javaws / usr / lib / jvm /java-8-oracle / bin / javaws 1

Теперь осталось выбрать версии исполняемых файлов java, javaws и javac, которые будут использоваться по умолчанию:

sudo update-alternatives —config java

sudo update-alternatives —config javac

sudo update-alternatives —config javaws

ArchLinux

Для начала просмотрите список установленных сред:

Затем установите необходимую вам:

archlinux-java set имя_среды

archlinux-java set java-8-jre/jre

CentOS

Выбрать необходимую среду можно с помощью команд, данных ниже (так же, как и в Ubuntu). Вам нужно будет просто выбрать цифру, соответствующую номеру версии:

sudo update-alternatives —config java

sudo update-alternatives —config javac

sudo update-alternatives —config javaws

Настройка переменных окружения

Чтобы настройки были доступны для всех пользователей, будем использовать файл /etc/profile. Откройте его для редактирования любым текстовым редактором с помощью команды sudo и добавьте в конец следующие строки:

1. export JAVA_HOME=/opt/java/jdk*/
2. export JRE_HOME=/opt/java/jdk*/jre
3. export PATH=$PATH:/opt/java/jdk*/bin:/opt/java/jdk*/jre/bin

• Вместо пути по умолчанию /opt/java укажите тот, который использовали;
• Если вы используете не JDK, а JRE, то в пути у вас так же будет не «jdk*», а «jre*»;
• «*» — версия Java, которая у вас установлена.

Выводы

В данной статье мы подробно разобрали процесс установки и настройки Java в различных дистрибутивах Linux. Если остались вопросы, спрашивайте в комментариях!

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6 JDK Installation for Linux Platforms

This page describes JDK for Linux system requirements and gives installation instructions for several JDK-Linux combinations.

This page contains these topics:

See «JDK 8 and JRE 8 Installation Start Here» for general information about installing JDK 8 and JRE 8.

For information on enhancements to JDK 8 that relate to the installer, see «Installer Enhancements in JDK 8».

System Requirements

See http://www.oracle.com/technetwork/java/javase/certconfig-2095354.html for information about supported platforms, operating systems, and browsers.

On a 64-bit system, you can download either the 64-bit or the 32-bit version of the Java platform. However, if you are using a 32-bit browser and you want to use the plugin, then you need to install the 32-bit version of the Java platform. To determine which version of Firefox you are running, launch the application, and select the menu item Help -> About Mozilla Firefox. At the bottom of the window is a version string line that contains either «Linux i686» (32-bit) or «Linux x86_64» (64-bit). To setup the Java plugin, see «Manual Installation and Registration of Java Plugin for Linux».

JDK 8 Installation Instructions

This topic describes:

Installation Instructions Notation and Files

For instructions containing the notation version , substitute the appropriate JDK update version number. For example, if you are installing update JDK 8 update release 2, the following string representing the name of the bundle:

Note that, as in the preceding example, the version number is sometimes preceded with the letter u , for example, 8u2 , and sometimes it is preceded with an underbar, for example, jdk1.8.0_02 .

The following table lists the options and instructions for downloading the JDK 8 release on a Linux platform.

Download File and Instructions	Architecture (CPU Type)	Who Can Install
For Linux x64 systems: jdk-8u version -linux-x64.tar.gz «Installation of the 64-bit JDK on Linux Platforms»	Intel — 64-bit	anyone
For Linux aarch64 (64-bit ARM) systems: jdk-8u version -linux-aarch64.tar.gz (version 8u271 and later) «Installation of the 64-bit JDK on Linux Platforms	ARM — 64-bit	anyone
For Linux x86 systems: jdk-8u version -linux-i586.tar.gz «Installation of the 32-bit JDK on Linux Platforms»	Intel — 32-bit	anyone
For Linux x64 systems: jdk-8u version -linux-x64.rpm «Installation of the 64-bit JDK on RPM-based Linux Platforms»	Intel — 64-bit RPM-based Linux	root
For Linux aarch64 (64-bit ARM) systems: jdk-8u version -linux-aarch64.rpm (version 8u271 and later) «Installation of the 64-bit JDK on RPM-based Linux Platforms»	ARM — 64-bit RPM-based Linux	root
For Linux x86 systems: jdk-8u version -linux-i586.rpm «Installation of the 32-bit JDK on RPM-based Linux Platforms»	Intel — 32-bit RPM-based Linux	root

Installation can be performed using either of the following:

Installation of JDK using archive files ( .tar.gz ) allows you to install a private version of the JDK for the current user into any location, without affecting other JDK installations. However, it may involve manual steps to get some of the features to work (for example, the -version: release option of the java command, which allows you to specify the release to be used to run the specified class, requires the correct path to the JDK release under /usr/jdk ).

Installation of JDK using RPM packages allows you to perform a system-wide installation of the JDK for all users, and requires root access.

When you download and install the Java Development Kit (JDK), the associated Java Runtime Environment (JRE) is also installed.

JDK 7u6 and later releases include JavaFX SDK (version 2.2 or later). The JavaFX SDK and Runtime are installed and integrated into the standard JDK directory structure.

Installation of the 64-bit JDK on Linux Platforms

This procedure installs the Java Development Kit (JDK) for 64-bit Linux, using an archive file ( .tar.gz ).

These instructions use the following files:

jdk-8uversion-linux-x64.tar.gz and jdk-8uversion-linux-aarch64.tar.gz (version 8u271 and later) for 64-bit ARM systems.

Download the required file.

Before the file can be downloaded, you must accept the license agreement. The archive file can be installed by anyone (not only root users), in any location that you can write to. However, only the root user can install the JDK into the system location.

Change directory to the location where you would like the JDK to be installed, then move the .tar.gz archive file to the current directory.

Unpack the archive file and install the JDK.

• For x64 — % tar zxvf jdk-8uversion-linux-x64.tar.gz
• For 64-bit ARM system — % tar zxvf jdk-8uversion-linux-aarch64.tar.gz

The Java Development Kit files are installed in a directory called jdk1.8.0_ version in the current directory.

Delete the .tar.gz file if you want to save disk space.

Installation of the 64-bit JDK on RPM-based Linux Platforms

This procedure installs the Java Development Kit (JDK) for 64-bit RPM-based Linux platforms, such as Oracle, Red Hat and SuSE, using an RPM binary file ( .rpm ) in the system location. You must be root to perform this installation.

These instructions use the following files:

jdk-8uversion-linux-x64.rpm and jdk-8uversion-linux-aarch64.rpm (version 8u271 and later) for 64-bit ARM systems.

Download the required file.

Before the file can be downloaded, you must accept the license agreement.

Become root by running su and entering the super-user password.

Uninstall any earlier installations of the JDK packages.

Install the package:

• For x64 — # rpm -ivh jdk-8uversion-linux-x64.rpm
• For 64-bit ARM system — # rpm -ivh jdk-8uversion-linux-aarch64.rpm

To upgrade a package:

• For x64 — # rpm -Uvh jdk-8uversion-linux-x64.rpm
• For 64-bit ARM system — # rpm -Uvh jdk-8uversion-linux-aarch64.rpm

Delete the .rpm file if you want to save disk space.

Exit the root shell. No need to reboot.

Starting with version 8u40, the JDK installation is integrated with the alternatives framework and after installation, the alternatives framework is updated to reflect the binaries from the recently installed JDK. Java commands such as java , javac , javadoc , and javap can be invoked from the command line.

Using the java -version command, users can confirm the default (recently installed) JDK version.

In addition, users can now check which specific RPM package provides the java files:

Change in Communication With the Alternatives Framework of JDK RPM Installer Starting With JDK 8u261

Prior to JDK 8u261, the JDK RPM installers registered two groups of symbolic links with the alternatives framework, java and javac . In some versions of the alternatives framework, certain link names in these groups were duplicated, which resulted in installation failures.

Starting with JDK 8u261, the JDK RPM doesn’t register the javac group with the alternatives framework. All links unique to the javac group are moved into the java group, but the set of symbolic links registered by the installer are not changed; only the duplicated links have been dropped.

The implication of this change is that if you install JDK 8u261 and JDK 8u251 (or older versions) and uninstall JDK 8u261, the symbolic links from the java group that are managed by the alternatives framework will be deleted. To restore the deleted links, run the following command:

Installation of the 32-bit JDK on Linux Platforms

This procedure installs the Java Development Kit (JDK) for 32-bit Linux, using an archive file ( .tar.gz ).

These instructions use the following file:

Download the file.

Before the file can be downloaded, you must accept the license agreement. The archive file can be installed by anyone (not only root users), in any location that you can write to. However, only the root user can install the JDK into the system location.

Change directory to the location where you would like the JDK to be installed, then move the .tar.gz archive file to the current directory.

Unpack the archive file and install the JDK.

The Java Development Kit files are installed in a directory called jdk1.8.0_ version in the current directory.

Delete the .tar.gz file if you want to save disk space.

Installation of the 32-bit JDK on RPM-based Linux Platforms

This procedure installs the Java Development Kit (JDK) for 32-bit RPM-based Linux platforms, such as Red Hat and SuSE, using an RPM binary file ( .rpm ) in the system location. You must be root to perform this installation.

These instructions use the following file:

Download the file.

Before the file can be downloaded, you must accept the license agreement.

Become root by running su and entering the super-user password.

Uninstall any earlier installations of the JDK packages.

Install the package.

To upgrade a package:

Exit the root shell. No need to reboot.

Delete the .rpm file if you want to save disk space.

Starting with version 8u40, the JDK installation is integrated with the alternatives framework and after installation, the alternatives framework is updated to reflect the binaries from the recently installed JDK. Java commands such as java , javac , javadoc , and javap can be invoked from the command line.

Using the java -version command, users can confirm the default (recently installed) JDK version.

In addition, users can now check which specific RPM package provides the java files:

Installation of Public Key on RPM-based Linux Platforms

Since JDK version 8, the JDK RPMs are signed with OL keys. Installation of these RPMs on Linux distributions other than OL gives a warning message indicating that security validation of the package fails. This indicates that the public key used to sign this RPM needs to be installed in the system. A sample warning message and the public key installation steps are as follows:

Sample Warning Message

Installation Steps

Download the key file from https://yum.oracle.com/RPM-GPG-KEY-oracle-ol7 using the following command:

Install the key using the following command:

sudo rpm —import RPM-GPG-KEY-oracle-ol7

Public key installation needs to be done only once. The key installation is persistent across reboots.

General Installation Notes

This topic describes general installation topics.

Root Access

Installing the software automatically creates a directory called jdk1.8.0_ version . Note that if you choose to install the JDK into system-wide location, such as /usr/jdk , you must first become root to gain the necessary permissions. If you do not have root access, simply install the JDK into your home directory, or a subdirectory that you have permission to write to.

Overwriting Files

If you install the software in a directory that contains a subdirectory named jdk1.8.0_ version , the new software overwrites files of the same name in that jdk1.8.0_ version directory. Please be careful to rename the old directory if it contains files you would like to keep.

System Preferences

By default, the installation script configures the system such that the backing store for system preferences is created inside the JDK’s installation directory. If the JDK is installed on a network-mounted drive, it and the system preferences can be exported for sharing with Java runtime environments on other machines.

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