Raw javascript mongodb queries using db.eval() in java

currently I'm working on a project in JAVA, and I need to run the Javascript Mongo queries through JAVA, and I figured I can do something like that using db.eval() in java. Problem is I have the following Javascript query for Mongo, and I have no idea how can I pass the whole Script to the db.eval() method. Any idea ? please let me know. thank you

    var red = function(doc, out) {
    out.count_order++;
    out.sum_qty += doc.quantity;
    out.sum_base_price += doc.extendedprice;
    out.sum_disc_price += doc.extendedprice * (1 - doc.discount);
    out.sum_charge += doc.extendedprice * (1 - doc.discount) * (1 + doc.tax);
    out.avg_disc += doc.discount 
    };
    var avg = function(out) {
    out.avg_qty = out.sum_qty / out.count_order;
    out.avg_price = out.sum_base_price / out.count_order;
    out.avg_disc = out.avg_disc / out.count_order 
    };
    db.deals.group( {
    key : { RETURNFLAG : true, LINESTATUS : true},
    cond : { "SHIPDATE" : {$lte: new Date(1998, 8, 1)}},
    initial: { count_order : 0, sum_qty : 0, sum_base_price : 0, sum_disc_price : 0,
    sum_charge : 0, avg_disc : 0},
    reduce : red,
    finalize : avg
    });