What is the difference between javac and the Eclipse compiler?

What is the difference between javac and the Eclipse compiler?


Eclipse's built-in compiler is based on IBM's Jikes java compiler.
(Note that Eclipse also started its life at IBM).
It is completely independent of Sun's Java compiler in the JDK;

Another difference is that the Eclipse Compiler allows for incremental builds from within the Eclipse IDE, i.e. all code is compiled as soon as you finish typing.
The fact that Eclipse comes with its own compiler is also apparent because you can write, compile, and run Java code in Eclipse without even installing the Java SDK.
Few examples where ECJ is preferred over javac - Apache Tomcat uses ECJ to compile JSPs, IntelliJ IDEA has support ECJ, as of GCJ 4.3, GCJ integrates with ECJ, Liferay Builds with ECJ


An incremental Java compiler. Implemented as an Eclipse builder, it is based on technology evolved from VisualAge for Java compiler. In particular, it allows to run and debug code which still contains unresolved errors.
http://stackoverflow.com/questions/3061654/what-is-the-difference-between-javac-and-the-eclipse-compiler