How to generate class files form src java files in android? -

i trying build android project command line.i want convert .java file in src folder class files.i want generate class files in other location in /classes folder.please tell me how ?

i amusing follwing command error package r not exist

d:\androidtest\src\com\example\project>javac -d d:\androidtest\bin\cla sses -classpath c:\users\admin\android-sdks\platforms\android-19\android.jar;d:\ androidtest\gen\com\example\project\r.java *.java 

give following command while compiling program

javac -d c:\folder_path\classes

for more details refer java documentation @ following link http://docs.oracle.com/javase/7/docs/technotes/tools/windows/javac.html