How to Uninstall JAVA
Although the power of Java applications is well-known, so are the drawbacks – namely, various security risks. Although Oracle semi-regularly issues updates that close these exploitable weaknesses, PC and other device users have every right of preferring a more limited but safe environment. Those who would like to remove all Java capabilities altogether can do so with not much more trouble than removing any other program would require.
Before proceeding, note that most Web browsers and many add-ons provide extensive controls over features such as Java and Flash. Since some websites and applications have Java requirements, it might be preferable to restrict its use on unwanted sites instead of completely removing it from the device. For instance, the 'Java' section of the Windows Control Panel provides controls for enabling or restricting Java browser content and changing how Java applications behave according to their certificates (digital credentials that verify their identity and safety).
Windows users who want to remove Java anyway can start by removing it, similar to other applications. Type 'Add or remove programs' or type 'Control Panel' and click the 'Uninstall a program' link in the 'Programs' section of the Control Panel. Both options bring up a list of currently installed software. Although users can search them or filter them by criteria such as installation dates, these lists should be in alphabetical order. Find the Java installation, select it and choose to Uninstall.
Some users also may prefer running a Java-specific uninstall tool, such as JavaRa. These programs can delete leftover Registry entries, files, and other clutter associated with old Java installations. Experts recommend against manually altering the Registry, except for experienced users who know what they're doing – deleting the wrong Registry entries can damage Windows and other programs. Fortunately, using JavaRa mostly is self-explanatory; click 'next' after launching it and click the 'Perform Removal Routine' button afterward.
Apple hardware users have slightly-different options for removing Java. Somewhat uniquely, and unlike other software, installed Java will display its shortcut icon in the 'System Preferences' area. Users can click this icon and the Security tab to access their equivalent browser and certificate-based Java-limiting settings. A second Security tab in the Safari browser provides another way of restricting Java on websites by going to the Plug-In Settings section.
Most macOS programs are removable by click-dragging them to the Trash (the macOS equivalent of a Windows Recycle Bin). For some software, such as Java, this option is unavailable. However, users have a more technical way of getting rid of Java anyway. First, open the Terminal (it's in the Utilities section of Finder). Type the following commands and, after typing each one, press Enter:
sudo rm -fr ~/Library/Application\ Support/Java
sudo rm -fr /Library/PreferencePanes/JavaControlPanel.prefPane
sudo rm -fr /Library/Internet\ Plug-Ins/JavaAppletPlugin.plugin
These commands delete all Java components with root privileges.
No price for security is too high, and users shouldn't uncomfortably submit to programs wasting hard drive space. In that respect, Java is no different from any other software, and no one should be shy about moving on from it.