Random sentence generator

[BrAD19924]

Im new to java and i have a program but i have no idea what to do. It needs to be a recursive program to generate random sentences from a given BNF grammar. the user should be able to enter the name of the input file on command line: ex. java Sentences bnf.txt. It should look like this when done.
Enter number of sentences: (a number)
Here are the sentences:
....
.....


can some one help

[BrAD19924]

and the bnf file looks like
<s>::= <np> <vp>
<np>::= <dp> <adjp> <n>|<pn>
<dp>::= the|a
<adjp>::= <adj>| <adj> <adjp>
<adj>::= big|fat|green...
<n>::=dog|cat...
<pn>::=John|MArry...
<vp>::=<tv> <np>|<iv>
<tv>::= hit|honored...
<iv>::=died|collapsed....

Im new to java and i have a program but i have no idea what to do. It needs to be a recursive program to generate random sentences from a given BNF grammar. the user should be able to enter the name of the input file on command line: ex. java Sentences bnf.txt. It should look like this when done.
Enter number of sentences: (a number)
Here are the sentences:
....
.....


can some one help

[ozzyman]

you can start off with this helpful tutorial

Scanning (The Java™ Tutorials > Essential Classes > Basic I/O)

[BrAD19924]

i no how to use scanner already thanks for the suggestion i just dont no how to read in that txt file make it into an array and then give it random number s then put what it comess up with all together to make a sentence

[Green_Ghoul]

A hashmap would be a good start

[ozzyman]

regex might be helpful
String Literals (The Java™ Tutorials > Essential Classes > Regular Expressions)

also String.replaceAll(String regex, String replacementString)

[BrAD19924]

im just not going to attempt it seems way over my head, but it would be cool to see actually work