Is Eclipse a Java compiler?
No, Eclipse has its own Java compiler. The compiler itself is included in the org.eclipse.jdt.core plugin. Eclipse won’t use any user installed JDK. Instead it uses its own JDT core to compile Java program due to the following primary reason:
The primary reason is that JDT core has the ability of incremental compilation, which means that it incrementally compiles changes in your code (this is also why Eclipse does not need a compilation button because it automatically compiles when changes are detected). But Oracle’s JDK does not support incremental compilation.