Objectives.
1. Support multiline comments.
2. Support additional tokens (reserved words, operators, and separators).
3. Support long and double literals.
In this project, you will only be updating the hand-crafted scanner, which means that the only program files you will be modifying under $j/j–/src/jminusminus are TokenInfo.java and Scanner.java.
Run the following command inside the $j directory to compile the j– compiler with your changes.
$ ant clean com pile jar
Run the following command to compile (just scan for now) a j– program P.java using the j– compiler.
$ sh $j /j – -/ bin /j – – -t P . java
which only scans P.java and prints the tokens in the program along with the line number where each token appears.
Problem 1. (Multiline Comment ) Add support for multiline comment, where all the text from the ASCII characters /* to the ASCII characters */ is ignored.
$ $j /j - -/ bin /j - - -t tests / M ultiL ineC om m ent . java
5 : public = public
5 : class = class
5 : < IDENTIFIER > = M ultiL ineC om m ent 5 : { = {
9 : public = public
9 : static = static
9 : void = void
9 : < IDENTIFIER > = main
9 : ( = (
9 : < IDENTIFIER > = S tring
9 : [ = [
9 : ] = ]
9 : < IDENTIFIER > = args
9 : ) = )
9 : { = {
13 : } = }
14 : } = }
15 : < EOF > = < EOF >
Problem 2. (Reserved Words) Add support for the following reserved words.
|
break |
case |
catch |
|
continue |
default |
do |
|
double |
final |
finally |
|
for |
im plem ents |
interface |
|
long |
sw itch |
throw |
|
throw s |
try |
$ $j /j - -/ bin /j - - -t tests / R eserved W ords . java 1 : break = break 1 : case = case 1 : catch = catch 2 : continue = continue 2 : default = default 2 : do = do 3 : double = double 3 : final = final 3 : finally = finally 4 : for = for 4 : im plem ents = im plem ents 4 : interface = interface
Problem 3. (Operators) Add support for the following operators.
|
? |
~ |
!= |
/ |
/= |
|
-= |
— |
*= |
|
|
|
>> |
> >= |
> > > |
> > >= |
>= |
|
<< |
< <= |
< |
^ |
^= |
|
| |
|= |
|| |
& |
&= |
$ $j /j - -/ bin /j - - -t tests / O perators . java 1 : ? = ? 1 : ~ = ~ 1 : != = != 1 : / = / 1 : /= = /= 2 : -= = -= 2 : -- = -- 2 : *= = *= 2 : = 2 : = = = 3 : >> = >> 3 : > >= = > >= 3 : > > > = > > > 3 : > > >= = > > >= 3 : >= = >= 4 : << = << 4 : < <= = < <= 4 : < = < 4 : ^ = ^ 4 : ^= = ^= 5 : | = | 5 : |= = |= 5 : || = || 5 : & = & 5 : &= = &= 6 : < EOF > = < EOF >
Problem 4. (Separators) Add support for the separator : (colon).
$ $j /j - -/ bin /j - - -t tests / S eparators . java 1 : ; = ;
2 : : = :
3 : , = ,
4 : . = .
5 : [ = [
5 : { = {
5 : ( = (
5 : ) = )
5 : } = }
5 : ] = ]
6 : < EOF > = < EOF >
Problem 5. (Literals) Add support for (just decimal for now) long and double literals.
< int_literal > = 0 | (1 -9) {0 -9} // decim al
< long_literal > = < int_literal > ( l | L )
< digits > = (0 -9) {0 -9}
< exponent > = ( e | E ) [(+ | -)] < digits >
< suffix > = d | D
< double_literal > = < digits > . [< digits >] [< exponent >] [< suffix >]
| . < digits > [< exponent >] [< suffix >]
| < digits > < exponent > [< suffix >]
| < digits > [< exponent >] < suffix >
$ $j /j - -/ bin /j - - -t tests / L iterals . java 1 : < IN T _LIT E R A L > = 0 1 : < IN T _LIT E R A L > = 2 1 : < IN T _LIT E R A L > = 372 2 : < L O N G _L IT E R A L > = 1996 l 2 : < L O N G _L IT E R A L > = 777 L 2 : < D O U B L E _L IT E R A L > = .3 D 3 : < D O U B L E _L IT E R A L > = 3.14 3 : < D O U B L E _L IT E R A L > = 6.022137 e +23 3 : < D O U B L E _L IT E R A L > = 1e -9 d 4 : < EOF > = < EOF >
Files to Submit
1. j–.tar.gz (j– source tree as a single gzip file)
2. report.txt (project report)
$ cd $j /j -- $ ant clean $ cd .. $ tar - cvf j - -. tar j - -/* $ gzip j - -. tar
