@SuppressWarnings("null")
	public final DFAState getPrecedenceStartState(int precedence) {
		if (!isPrecedenceDfa()) {
			throw new IllegalStateException("Only precedence DFAs may contain a precedence start state.");
		}

		// s0.edges is never null for a precedence DFA
		if (precedence < 0 || precedence >= s0.edges.length) {
			return null;
		}

		return s0.edges[precedence];
	}
Get the start state for a specific precedence value.

@param precedence The current precedence.
@return The start state corresponding to the specified precedence, or
{@code null} if no start state exists for the specified precedence.

@throws IllegalStateException if this is not a precedence DFA.
@see #isPrecedenceDfa()
runtime/Java/src/org/antlr/v4/runtime/dfa/DFA.java