title: make file for Java/Linux
body: <p>I have the following makefile after running it once I make some changes to the makefile and now when I run it I get a "make: Nothing to be done for `default'."  How can I force it to rebuild?  I execute "make" and also "make clean" and I still get the error message when I type "make".</p>
  
  <p>Also, how do I get the log4.properties file which is in the src directory to be copied over to the target directory (in the make file and on the command line: javac -classpath src:lib/log4j-1.2.16.jar src/*.java -d bin)?  </p>
  
  <pre>
  #
  # define compiler and compiler flag variables
  #
  
  JFLAGS = -g -cp .:src:lib/log4j-1.2.16.jar
  JC = javac
  
  
  #
  # Clear any default targets for building .class files from .java files; we 
  # will provide our own target entry to do this in this makefile.
  # make has a set of default targets for different suffixes (like .c.o) 
  # Currently, clearing the default for .java.class is not necessary since 
  # make does not have a definition for this target, but later versions of 
  # make may, so it doesn't hurt to make sure that we clear any default 
  # definitions for these
  #
  
  .SUFFIXES: .java .class
  
  
  #
  # Here is our target entry for creating .class files from .java files 
  # This is a target entry that uses the suffix rule syntax:
  #   DSTS:
  #       rule
  #  'TS' is the suffix of the target file, 'DS' is the suffix of the dependency 
  #  file, and 'rule'  is the rule for building a target  
  # '$*' is a built-in macro that gets the basename of the current target 
  # Remember that there must be a  before the command line ('rule') 
  #
  
  .java.class:
      $(JC) $(JFLAGS) $*.java
  
  
  #
  # CLASSES is a macro consisting of 4 words (one for each java source file)
  #
  
  CLASSES = \
      src/MatrixDriver.java \
      src/ConcreteMatrix.java \
      src/Matrix.java \
      src/Submatrix.java 
  
  
  #
  # the default make target entry
  #
  
  default: classes
  
  
  #
  # This target entry uses Suffix Replacement within a macro: 
  # $(name:string1=string2)
  #   In the words in the macro named 'name' replace 'string1' with 'string2'
  # Below we are replacing the suffix .java of all words in the macro CLASSES 
  # with the .class suffix
  #
  
  classes: $(CLASSES:.java=.class)
  
  
  #
  # RM is a predefined macro in make (RM = rm -f)
  #
  
  clean: FORCE
      $(RM) *.class
  
  FORCE:
  
  </pre>