Where is the source code of java written (Java Program Editor)?

Following are the few most popular text-editors where one can write the Java’s source code.

Notepad / Notepad: basically used by the new Java’s programmers or for simple java programs.
Eclipse: This is a very good Java IDE for making Java program, it is open-source and free.
Netbean: This IDE is also very good for Java, it is also open-source and free.
Bluej: This IDE is specially made for Java, it is also open-source and free of cost. This IDE requires JDK (Java Development Kit).

Must Read – Structure for Java Program