Question

I am getting a “No matching ctor found” error while trying to populate a Java class from Clojure.

I want to populate this class from Clojure.

import java.util.Date;

public class Account {
    Account() { acct_num = 0; 
                trans_type = 'U';
                trans_amt = 0.00;
                cur_bal = 0.00;
                last_update = null;
               }

    public int acct_num = 0;
    public char trans_type;
    public double trans_amt = 0.00;
    public double cur_bal = 0.00;
    public Date last_update;
}

I can import the class:

ba2-app=> (ns ba2-app (:import Account))
Account

but when I go to populate it, I get this error:

ba2-app=> (:use java.util.Date)
nil
ba2-app=> (Account. 1000 \C 100.00 0.00 (java.util.Date. "12/21/2011"))
java.lang.IllegalArgumentException: No matching ctor found for class Account (NO_SOURCE_FILE:9)

I followed these suggestions to get the Java class built in with my Clojure code. The suggestions which were very helpful, because I can now build the Java class.

Any pointers or suggestions would be helpful. I know the class members should be private, but this is to test out a larger project.

Answer 1

Make the constructor public with the public access modifier. Also your constructor doesn’t accept any args, but just sets a bunch of members to some values. So you can now actually only call it like: (Account.) (if it were public).

When you want to use a constructor like this: (Account. 1000 \C 100.00 0.00 (java.util.Date. "12/21/2011")) you’ll have to add a constructor that accepts these types of arguments:

    public Account(int a, char c, double d1, double d2, Date date) { 
      acct_num = a; 
      trans_type = c;
      trans_amt = d1;
      cur_bal = d2;
      last_update = date;
    }