fix makefile

makefile

@@ -1,4 +1,4 @@
-.PHONY: all
+.PHONY: all clean permissions
 
 # Define the target executable
 TARGET = JavaCrypt.jar
@@ -10,7 +10,7 @@ SRC_DIR = javacrypt
 SRC_FILES = $(wildcard $(SRC_DIR)/*.java)
 
 # Define the compiler and flags
-JAVAC = /usr/lib/jvm/default-java/bin/javac
+JAVAC = /usr/bin/javac
 JAR = jar
 JAVAC_FLAGS = -Xlint:unchecked
 
@@ -23,7 +23,14 @@ $(TARGET): $(SRC_FILES)
 	@$(JAVAC) $(JAVAC_FLAGS) $(SRC_FILES)
 	@echo "Creating the JAR archive..."
 	@$(JAR) cfm $(TARGET) manifest.mf $(SRC_DIR)/*.class
+
+# Rule to clean up the build artifacts
+clean:
 	@echo "Cleaning up..."
 	@rm -rf $(TARGET) $(SRC_DIR)/*.class
 	@echo "Done!"
 
+# Rule to set execution permissions for the JAR archive
+permissions:
+	@echo "Setting execution permissions for the JAR archive..."
+	@chmod +x $(TARGET)