ANTLR4 Exrpression evaluator error

I wanted to try this sample code out but i cannot get it to run because i am having compiling errors. I also added an image of my eclipse.

which whos where the errors are.

Here is the Grammar:

grammar Expr;
eval
: expr EOF
;
expr
: expr '*' expr #mult_expr
| expr '/' expr #div_expr
| expr '+' expr #add_expr
| expr '-' expr #min_expr
| '(' expr ')' #par_expr
| NUMBER #num_expr
| IDENTIFIER #id_expr
;
MULT : '*';
DIV : '/';
ADD : '+';
MIN : '-';
OPAR : '(';
CPAR : ')';
NUMBER
: [0-9]+ ('.' [0-9]*)?
| '.' [0-9]+
;
IDENTIFIER
: [a-zA-Z_] [a-zA-Z_0-9]*
;
SPACES
: [ \t\n\r]+ -> skip
;

Here is the EvalVisitor.Java class i am having problems with, its says: The method visit(ExprParser.ExprContext) is undefined for the type EvalVisitor.

package nl.bigo.antlr4template;
import org.antlr.v4.runtime.misc.NotNull;
import java.util.Map;
public class EvalVisitor extends ExprBaseVisitor<Double> {
    private final Map<String, Double> variables;
    public EvalVisitor(Map<String, Double> variables) {
        this.variables = variables;
    }
    public Double visitMin_expr(@NotNull ExprParser.Min_exprContext ctx) {
        return this.visit(ctx.expr(0)) - this.visit(ctx.expr(1));
    }
    public Double visitId_expr(@NotNull ExprParser.Id_exprContext ctx) {
        String id = ctx.IDENTIFIER().getText();
        Double value = variables.get(id);
        if (value == null) {
            throw new RuntimeException("unknown variable: " + id);
        }
        return value;
    }
    public Double visitDiv_expr(@NotNull ExprParser.Div_exprContext ctx) {
        return this.visit(ctx.expr(0)) / this.visit(ctx.expr(1));
    }

    public Double visitMult_expr(@NotNull ExprParser.Mult_exprContext ctx) {
        return this.visit(ctx.expr(0)) * this.visit(ctx.expr(1));
    }

    public Double visitEval(@NotNull ExprParser.EvalContext ctx) {
        return super.visit(ctx.expr());
    }

    public Double visitNum_expr(@NotNull ExprParser.Num_exprContext ctx) {
        return Double.valueOf(ctx.NUMBER().getText());
    }

    public Double visitPar_expr(@NotNull ExprParser.Par_exprContext ctx) {
        return super.visit(ctx.expr());
    }

    public Double visitAdd_expr(@NotNull ExprParser.Add_exprContext ctx) {
        return this.visit(ctx.expr(0)) + this.visit(ctx.expr(1));
    }
}


    grammar Expr;
parse : definition+;
definition  : VARIABLE '='  expression ';' ;
expression
 : expression expression                   # Application
 | '(' expression ')'                      # Bracket
 | expression INFIX_OP expression          # Infix
 | PREFIX_OP '(' expression ')'            # Prefix
 | '{' (expression (',' expression)*)? '}' # Set
 | '(' expression ',' expression ')'       # Pair
 | NUMBER                                  # Number
 | VARIABLE                                # Variable
 | <assoc=right> expression '=' expression # Equality
;
INFIX_OP : 'in' | 'U' | 'I' | '\\';
PREFIX_OP : [@][a-z-]+;
VARIABLE : [x][0-9]+ ;
NUMBER : [0-9]+ ;
WS : [ \t\r\n]+ -> skip ; // skip spaces, tabs, newlines
LINE_COMMENT : '#' ~[\r\n]* -> skip;