To use the Hadoop Java API, you must be able to compile the Java sources with the Hadoop library. An easy way is to use a prepared Makefile:

1. Create a directory for the Java sources.
2. Create a Makefile containing

   Makefile

   include /net/projects/hadoop/java/Makefile

When typing make, every Java file is compiled (with the Hadoop library and some extra classes) to a jar file. It is of course possible to compile just selected sources using make file1.jar file2.jar.

Command make clean remove for every Java file its jar file and subdirectory with compiled classes.

Create a directory and a Makefile as described and download WordCount.java. Try compiling it using make.

If you like using VIM, there is a special configuration available for editing Hadoop java files. Just execute

/net/projects/hadoop/vim

instead of vim.

This configuration of VIM

• can run make in current directory by pressing F7 (both in normal and insert mode). The file being edited is automatically saved.