# define compiler and compiler flag variables # define a variable for compiler flags (JFLAGS) # define a variable for the compiler (JC) # define a variable for the Java Virtual Machine (JVM) JFLAGS = -g JC = javac JVM = java # # 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 # DSTS (Dependency Suffix Target Suffix) # '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 < tab > before the command line ('rule') # .java.class: $(JC) $(JFLAGS) $*.java # # CLASSES is a macro consisting of N words (one for each java source file) # When a single line is too long, use \ to split lines that then will be # considered as a single line. For example: # NAME = Camilo \ Juan # is understood as # NAME = Camilo Juan CLASSES = \ HelloWorld.java # # MAIN is a variable with the name of the file containing the main method # MAIN = HelloWorld # # the default make target entry # for this example it is the target classes default: classes # Next line is a target dependency line # This target entry uses Suffix Replacement within a macro: # $(macroname:string1=string2) # In the words in the macro named 'macroname' 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) # Next two lines contain a target for running the program # Remember the tab in the second line. # $(JMV) y $(MAIN) are replaced by their values run: $(MAIN).class $(JVM) $(MAIN) # this line is to remove all unneeded files from # the directory when we are finished executing(saves space) # and "cleans up" the directory of unneeded .class files # RM is a predefined macro in make (RM = rm -f) # clean: $(RM) *.class