Eventually --- You May Need Java -- But Not All of the Time
Before I get started, I'd like to post a link with the answers to a lot of the questions people have about Java, What it Is, Why you Need it, etc.... This is directly from the Java website:
Java was originally developed by Sun Microsystems in 1995. Simply stated, Java is a programming language. You may have heard of other programming languages like C++, Fortran, BASIC, Pearl, and a host of others. Java is designed to "autostart" when you encounter a program written in the Java Programming Language. Essentially, it turns your computer into a "Java Virtual Machine" by taking control of the Java based program until you're finished with it.
Many people have removed Java from their computers with no negative effects. By that, I'm simply saying that these people don't use or need any of the products that integrate Java into their applications. As soon as they do chance upon such an instance, they will be promptly notified that a certain Version of Java is required to accomplish the task they're attempting to do, usually accompanied by a link to the Java site containing that code for download and installation.
Most people dislike Java because of the frequent updates. If you want Java to stop searching for updates and bugging you to install them all of the time, then turn off the update feature. It's located in the MSCONFIG STARTUP area --> Start -->type "msconfig" --> Select the Startup Tab --> Uncheck the box for Java autoupdate feature. Click on OK and then restart your computer. The Java will on longer prompt you to update.
As a programming language, I'm told that Java is clean and fast. It really shouldn't slow your computer down since it's not running until you chance upon a routine that requires it. If that happens, you're going to need it anyhow.
As browsers advance, they are becoming less and less dependent on Java and perform most tasks with the code written directly for the browser. To answer your question about safety, I'd say the Java program itself is completely safe. In fact, many security features are actually written in Java language. But there is always the potential of someone creating a pop-up that looks like the real Java update message in an attempt to infect your computer with a virus or malware. To prevent this, if you see a prompt (pop-up) for a Java Update ignore it, log onto your preferred Browser and go to Java.com and download the latest version. There is no need to delete the older version as since Java is designed to run multiple versions simultaneously. When you restart your computer the prompt should disappear.