How To Install Java To Library Mac

24-05-2021
 |  [RAND-100] - Comments

  1. How To Install Numpy
  2. How To Install Java To Library Mac Os

Macbook安装java终端输入java -version显示No Java runtime present, requesting install. 去oracle官网下载了JDK安装好以后。终端输入java -version一直显示No Java runtime present, requesting install. 解决办法为： 在终端中输入 vim.bashprofile 添加：.

This topic includes the following sections:

System Requirements for Installing the JDK on macOS

The following are the system requirements for installing the JDK on macOS:

  1. Brew cask install adoptopenjdk8-openj9 Fixed my problem and I can run my project in java8. Java -version. Openjdk version '1.8.0222. OpenJDK Runtime Environment (build 1.8.0222-b10) Eclipse OpenJ9 VM (build openj9-0.15.1, JRE 1.8.0 Mac OS X amd64-64-Bit Compressed References 20190717298 (JIT enabled, AOT enabled) OpenJ9 - 0f66c6431.
  2. 2018-2-4  brew cask是一个用命令行管理Mac下应用的工具，提供了自动安装和卸载功能，能够自动从官网上下载并安装 最新的版本，它是基于homebrew的一个增强工具。.

  • Any Intel-based computer running macOS.

  • Administrator privileges.

    You cannot install Java for a single user. Installing the JDK on macOS is performed on a systemwide basis for all users. Administrator privileges are required to install the JDK on macOS.

Determining the Default JDK Version on macOS

When starting a Java application through the command line, the system uses the default JDK.

There can be multiple JDKs installed on the macOS system.

You can determine which version of the JDK is the default by entering java -version in a Terminal window. If the installed version is 12 Interim 0, Update 0, and Patch 0, then you see a string that includes the text 12. For example:

To run a different version of Java, either specify the full path, or use the java_home tool. For example:

$ /usr/libexec/java_home -v 12 --exec javac -version

Installing the JDK on macOS

  1. Download the JDK .dmg file, jdk-12.interim.update.patch-macosx-x64.dmg.

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

  2. From either the browser Downloads window or from the file browser, double-click the .dmg file to start it.
    A Finder window appears that contains an icon of an open box and the name of the .pkg file.
  3. Double-click the JDK 12.pkg icon to start the installation application.
    The installation application displays the Introduction window.
  4. Click Continue.
  5. Click Install.
    A window appears that displays the message: Installer is trying to install new software. Enter your password to allow this.
  6. Enter the Administrator user name and password and click Install Software.
    The software is installed and a confirmation window is displayed.
After the software is installed, you can delete the .dmg file if you want to save disk space.

Uninstalling the JDK on macOS

You must have Administrator privileges.

Note:

Do not attempt to uninstall Java by removing the Java tools from /usr/bin. This directory is part of the system software and any changes will be reset by Apple the next time that you perform an update of the OS.

  1. Go to /Library/Java/JavaVirtualMachines.
  2. Remove the directory whose name matches the following format by executing the rm command as a root user or by using the sudo tool:
    /Library/Java/JavaVirtualMachines/jdk-interim.update.patch.jdk

    For example, to uninstall 12 Interim 0 Update 0 Patch 0:

    $ rm -rf jdk-12.jdk

Installation FAQ on macOS Platform

This topic provides answers for the following frequently asked questions about installing JDK on macOS computers.

1. How do I find out which version of Java is the system default?

When you run a Java application from the command line, it uses the default JDK. If you do not develop Java applications, then you do not need to worry about this. See Determining the Default JDK Version on macOS.

2. How do I uninstall Java?

See Uninstalling the JDK on macOS.

3. After installing Java for macOS 2012-006, can I continue to use Apple's Java 6 alongside the macOS JDK for Java 12?

If you want to continue to develop with Java 6 using command-line, then you can modify the startup script for your favorite command environment. For bash, use this:

$ export JAVA_HOME=`/usr/libexec/java_home -v 12`

Some applications use /usr/bin/java to call Java. After installing Java for macOS 2012-006, /usr/bin/java will find the newest JDK installed, and will use that for all of the Java-related command-line tools in /usr/bin. You may need to modify those applications to find Java 6, or contact the developer for a newer version of the application.

How To Install Numpy

4. Can I restore Apple Java after uninstalling Oracle Java?

How to install linux

Go back to Apple Java using the following instructions:

  1. Uninstall Oracle Java by deleting the plug-in file. From a command-line, enter:

    $ sudo rm -rf '/Library/Internet Plug-Ins/JavaAppletPlugin.plugin'

  2. Create a symlink using the following command, entered on a single line:

    $ sudo ln -s /System/Library/Java/Support/CoreDeploy.bundle/Contents/JavaAppletPlugin.plugin '/Library/Internet Plug-Ins/JavaAppletPlugin.plugin'

5. What happened to the Java Preferences app in Application Utilities?

How To Install Java To Library Mac Os

The Java Preferences app was part of the Apple Java installation and is not used by Oracle Java. Therefore, macOS releases from Apple that do not include Apple Java will not include Java Preferences.