Predictive parser you selected (LL(k)) means you will have to solve left-recursion problems. Algorithm for solving direct and indirect recursions is clearly described on wikipedia:

http://en.wikipedia.org/wiki/Left_recursion

Some info can be found in posts here on StackOverflow:

https://stackoverflow.com/questions/2652060/removing-left-recursion
https://stackoverflow.com/questions/2999755/removing-left-recursion-in-antlr
https://stackoverflow.com/questions/4994036/left-recursion-elimination

In human language (non-scientific 🙂 “left-recursion problem” means you can’t endlessly go into recursion with non-terminal (A -> Ab) again and again. At some time you HAVE TO feed parser algorithm with a terminal to breake a loop.

In BNF this could look like:

Recursion Problem:

NT: NT T
NT: T

One solution:

NT: T NT2
NT2: T NT2
NT2: 

For your grammar this could look like:

DataType:
    PrimitiveDataType ArrayDimensions
 |  ComplexDataType ArrayDimensions

ArrayDimensions:
    [] ArrayDimensions
 |

If your parser generator doesn’t allow empty productions and/or if you want to process array types separately, try something like this:

DataType:
    DataTypeName
 |  ArrayDataType

ArrayDataType:
    DataTypeName ArrayDimensions

DataTypeName:
    PrimitiveDataType
 |  ComplexDataType

ArrayDimensions:
    []
 |  [] ArrayDimensions

The problem is that using a LL(1) parser can lead to left-recursion. You can avoid this by switching to a LR parser or using this grammar to avoid recursion:

DataType:
    PrimitiveDataType ArrayDataType
 |  ComplexDataType ArrayDataType

ArrayDataType:
    [] ArrayDataType
 |  (empty)

If parsing is not part of your project, just search for a parsing library/generator, there are probably many out there.

The key here is simply to use an LR parser rather than LL. There’s a reason why virtually no implementations actually use LL as it’s stated, and it’s because it really can’t recognize many particularly useful grammars.

This problem you are facing looks with something I’ve already faced. In that case, it should be implemented in the Syntatic Analyzer class, and yes, it will generate a tree, it would be indeed recursive.

E.g.: in my case, I had to implement a way that the function would receive a list of arguments, so my grammar rule for arguments list would be something like this:

<ArgLi> ::= <Arg> <ArgLi> |

where:

<Arg> ::= '(' <Type> Identifier ')'

<ArgLi> is called recursivelly

<Type> ::= 'int' | 'real' | 'str'

Identifier = {ID Head}{ID Tail}*

So, to implement that feature, the command has delimiters, so even if it enters a loop, it will check the rule, and determine the action based on the current token I’m looking.

For example, let’s say I want to write this:

( def main [ ( int a1 ) ( str a2 )  ]

...

)

The code my language follows to understand this is:

/**
 * <Def> ::= '(' 'def' Identifier '[' <ArgLi> ']' <CommandLi> ')'
 */
public Node Def() {

    Node node = new Node(NodeIdentifier.DEF);
    if (token.getImage().equals("(")) {
        node.addSon(new Node(NodeIdentifier.TOKEN, token));
        token = readToken();
        if (token.getImage().equals("def")) {
            node.addSon(new Node(NodeIdentifier.TOKEN, token));
            token = readToken();
            if (token._getClass().equals("ID")
                    || token.getImage().equals("main")) {
                node.addSon(new Node(NodeIdentifier.TOKEN, token));
                token = readToken();
                if (token.getImage().equals("[")) {
                    node.addSon(new Node(NodeIdentifier.TOKEN, token));
                    token = readToken();
                    node.addSon(argLi());
                    if (token.getImage().equals("]")) {
                        node.addSon(new Node(NodeIdentifier.TOKEN, token));
                        token = readToken();
                        node.addSon(commandLi());
                        if (token.getImage().equals(")")) {
                            node.addSon(new Node(NodeIdentifier.TOKEN,
                                    token));
                            token = readToken();
                        } else {
                            errors.add("Error: token ')' not recognized. line: "
                                    + token.getLine());
                        }
                    } else {
                        errors.add("Error: token ']' not recognized. line: "
                                + token.getLine());
                    }
                } else {
                    errors.add("Error: token '[' not recognized. line: "
                            + token.getLine());
                }
            } else {
                errors.add("Error: token 'ID' not recognized. line: "
                        + token.getLine());
            }
        } else {
            errors.add("Error: token 'def' not recognized. line: "
                    + token.getLine());
        }
    } else {
        errors.add("Error: token '(' not recognized. line: "
                + token.getLine());
    }
    return node;
}

/**
 * <ArgLi> ::= <Arg> <ArgLi> |
 */
public Node argLi() {

    Node node = new Node(NodeIdentifier.ARGLI);
    if (token.getImage().equals("(")) {
        node.addSon(arg());
        node.addSon(argLi());
    }
    return node;
}

/**
 * <Arg> ::= '(' <Type> Identifier ')'
 */
public Node arg() {
    Node node = new Node(NodeIdentifier.ARG);
    if (token.getImage().equals("(")) {
        node.addSon(new Node(NodeIdentifier.TOKEN, token));
        token = readToken();
        node.addSon(type());
        if (token._getClass().equals("ID")) {
            node.addSon(new Node(NodeIdentifier.TOKEN, token));
            token = readToken();
            if (token.getImage().equals(")")) {
                node.addSon(new Node(NodeIdentifier.TOKEN, token));
                token = readToken();
            } else {
                errors.add("Error: token ')' not recognized. line: "
                        + token.getLine());
            }
        } else {
            errors.add("Error: token 'ID' not recognized. line: "
                    + token.getLine());
        }
    } else {
        errors.add("Error: token '(' not recognized. line: "
                + token.getLine());
    }

    return node;
}

As you can see the methods arg() and argLi() are called recursivelly, and that’s how I’ve implemented it to avoid infinit loops in an efficient way.

I’m pretty sure this technique can help you with your problem.