Shulou(Shulou.com)06/03 Report--

1. Check whether the jdk environment variable is set: echo $JAVA_HOME

2. Run the command: java-verion to see if you can check the version and run it if you can.

3. Check the background process: ps-ef | grep java.

Online learning video tutorials sharing: linux video tutorials

Linux directory structure:

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/ bin is used to store user commands. / usr/bin is also used to store user commands.

/ sbin the storage location of many system commands, such as shutdown. Many system commands are also included in / usr/sbin.

The home directory of the / root root user (superuser).

/ mnt this directory usually includes the mount point of the file system that is mounted after the system boots. For example, the default CD mount point is / mnt/cdrom/. You can build a mount point for the U disk: mkdir / mnt/usb.

/ boot includes files used by the kernel and other systems during startup, up to a maximum of 200m. Usually I build a primary partition for / boot that is 1G.

/ lost+found is used by fsck to place fragmented files (files with no names).

/ lib contains many library files used by programs in / bin and / sbin. The directory / usr/lib contains more library files for user programs. Placed in the / lib directory are the library files needed by the program in the / bin and / sbin directories. In short, / lib is kernel-level; / usr/lib is system-level; / usr/local/lib is user-level. Shared libraries used only by programs in the / usr directory do not have to be placed in the / lib directory. Only the libraries needed by the programs under / bin and / sbin need to be placed in the / lib directory.

/ dev stores equipment files.

/ etc contains many configuration files and directories.

/ var is used to store variable (or constantly changing) files, such as log files and printer spooling files, virtual machine images, etc.

/ usr includes files and directories that are directly related to system users, such as applications and library files that support them.

/ proc A virtual file system (not actually stored on disk) that contains system information used by some programs.

/ initrd is used to mount the directory of initrd.img image files and the directory where the required device modules are loaded when the computer starts. Do not delete the / initrd directory. If you delete this directory and then reboot Red Hat Linux, you will not be able to boot your computer.

Temporary directory for / tmp users and programs.

/ tmp gives all system users read and write rights.

The default location of the / home user home directory.

/ opt the storage directory of optional files and programs. This directory is mainly used by third-party developers to easily install and uninstall their software packages.

These are the details of how linux determines whether to install jdk. For more information, please pay attention to other related articles!

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