Examples with ExprParser io.druid.math.expr.antlr.ExprParser used on opensource projects

Example 1 with ExprParser

use of io.druid.math.expr.antlr.ExprParser in project druid by druid-io.

the class Parser method parse.

public static Expr parse(String in, boolean withFlatten) {
    ExprLexer lexer = new ExprLexer(new ANTLRInputStream(in));
    CommonTokenStream tokens = new CommonTokenStream(lexer);
    ExprParser parser = new ExprParser(tokens);
    parser.setBuildParseTree(true);
    ParseTree parseTree = parser.expr();
    ParseTreeWalker walker = new ParseTreeWalker();
    ExprListenerImpl listener = new ExprListenerImpl(parseTree);
    walker.walk(listener, parseTree);
    return withFlatten ? flatten(listener.getAST()) : listener.getAST();
}