public static boolean check_cmd(String line) {
// must have the length of 3 or 4
String line_test = line;
String[] line_arr = line.split("\\s+");
int line_length = line_arr.length;
if (line_length != 3 && line_length != 4) {
// it's a bad instruction!
BadInstructionObject bad_inst = new BadInstructionObject();
// set InstructionObject as "bad"
inst_obj.set_type("bad");
// feed to BadInstrution to ReferenceManager
ref_mgr.badInst(bad_inst);
// print state
printState();
return false;
}
// must have read or write in the first command
if ((!line_arr[0].toLowerCase().equals("read"))
&& (!line_arr[0].toLowerCase().equals("write"))) {
// it's a bad instruction!
BadInstructionObject bad_inst = new BadInstructionObject();
inst_obj.set_type("bad");
// feed to ReferenceManager
ref_mgr.badInst(bad_inst);
// print state
printState();
return false;
}
// format = string string string int, where int is optional
try {
Integer.parseInt(line_arr[1]);
// it's a bad instruction!
BadInstructionObject bad_inst = new BadInstructionObject();
inst_obj.set_type("bad");
// feed to Reference Manager
ref_mgr.badInst(bad_inst);
// print state
printState();
return false;
} catch (Exception e) {
// it is not an int! good! do nothing
}
try {
Integer.parseInt(line_arr[2]);
// it's a bad instruction!
BadInstructionObject bad_inst = new BadInstructionObject();
inst_obj.set_type("bad");
// feed to Reference Manager
ref_mgr.badInst(bad_inst);
// print state
printState();
return false;
} catch (Exception e) {
// it is not an int! good! do nothing
}
if (line_arr.length == 4) {
if (!line_arr[0].toLowerCase().equals("write")) {
// it's a "read" command with 4 length. INVALID!
// it's a bad instruction!
BadInstructionObject bad_inst = new BadInstructionObject();
inst_obj.set_type("bad");
// feed to Reference Manager
ref_mgr.badInst(bad_inst);
// print state
printState();
return false;
}
try {
cmd_value = Integer.parseInt(line_arr[3]);
// it is an int! good! do nothing!
// save!
main_cmd = line_arr[0] + "s";
} catch (Exception e) {
// last command is NOT int
// it's a bad instruction!
BadInstructionObject bad_inst = new BadInstructionObject();
inst_obj.set_type("bad");
// feed to Reference Manager
ref_mgr.badInst(bad_inst);
// print state
printState();
return false;
}
} else {
if (!line_arr[0].toLowerCase().equals("read")) {
// it's a "read" command with 4 length. INVALID!
// it's a bad instruction!
BadInstructionObject bad_inst = new BadInstructionObject();
inst_obj.set_type("bad");
// feed to Reference Manager
ref_mgr.badInst(bad_inst);
// print state
printState();
return false;
}
main_cmd = line_arr[0] + "s";
}
// save global for later use
subject_name = line_arr[1];
object_name = line_arr[2];
cmd_length = line_arr.length;
return true;
}
public static void main(String[] args) {
// create subjects with security label and inform
ref_mgr.createSubj("Lyle", 2);
ref_mgr.createSubj("Hal", 1);
// create objects with security label and inform
ref_mgr.createObj("Lobj", 2);
ref_mgr.createObj("Hobj", 1);
// read command line ########################################################
try {
File aFile = new File(args[0]);
Scanner sc = new Scanner(aFile);
System.out.println("Reading from file: " + args[0] + "\n");
while (sc.hasNextLine()) {
// case-insensitive, lower the case!
String line = sc.nextLine().toLowerCase();
// check for illegal commands
if (check_cmd(line)) {
if (cmd_length == 3) {
System.out.println(subject_name + " " + main_cmd + " " + object_name);
} else {
System.out.println(
subject_name + " " + main_cmd + " value " + cmd_value + " to " + object_name);
}
Scanner scLine = new Scanner(line);
// parse command
inst_obj.set_type(scLine.next());
inst_obj.set_subj(scLine.next());
inst_obj.set_obj(scLine.next());
// exeception-prone (takes last cmd if there is one)
try {
inst_obj.set_value(scLine.next());
} catch (NoSuchElementException e) {
// System.out.println("Error message: " + e.getMessage());
// e.printStackTrace();
}
scLine.close();
// feed to ReferenceManager
try {
ref_mgr.validate(inst_obj);
} catch (Exception e) {
System.out.println(e.getMessage());
}
// print state
printState();
}
}
sc.close();
} catch (IOException e) {
e.getMessage();
e.printStackTrace();
}
// done with read command line #############################################
// execute commands
// print states
}