java.lang.OutOfMemoryError

[nickyeng]

I keep getting this error:

java.lang.OutOfMemoryError: Java heap space
 

what possible reason that cause this error ?

My boss dont want increase java memory, so i had to change my code.

My code have sql statement and my database table has 60000 rows(record) and keep increasing.

I call this to retrieve data from table:

double total = Billing.getTotalAmount(String str);
 

so in that Billing class has a method called getTotalAmount which doing the sql statement and sum the amount for certain column amount and return it.

Still, it can't runs and give same error.

Any idea ?

thanks in advance
from
Nick

[r035198x]

I keep getting this error:

java.lang.OutOfMemoryError: Java heap space
 

what possible reason that cause this error ?

My boss dont want increase java memory, so i had to change my code.

My code have sql statement and my database table has 60000 rows(record) and keep increasing.

I call this to retrieve data from table:

double total = Billing.getTotalAmount(String str);
 

so in that Billing class has a method called getTotalAmount which doing the sql statement and sum the amount for certain column amount and return it.

Still, it can't runs and give same error.

Any idea ?

thanks in advance
from
Nick

You may need to post the getTotalAmount method ...

[nickyeng]

I didn't do like this until my boss ask me to give better solution to that OutOfMemoryError....

so this is the changed code after OutOfMemoryError, but still, it gets the same Error.

this is the code :

double total = 0;
Connection conn = DbConnectionManager.getConnection();
        try{
            PreparedStatement st = conn.prepareStatement("select sum(amount) from billing where no like \'"+no+"%\' and  billing_date like \""+String.valueOf(year)+"%\" ");
            ResultSet rs = st.executeQuery();
            while(rs.next())
                total = rs.getDouble(1);
 
            rs.close();
            st.close();
 
                        return total;
        }finally
        {
            DbConnectionManager.release(conn);
        }
 
 
 

[r035198x]

I didn't do like this until my boss ask me to give better solution to that OutOfMemoryError....

so this is the changed code after OutOfMemoryError, but still, it gets the same Error.

this is the code :

double total = 0;
Connection conn = DbConnectionManager.getConnection();
        try{
            PreparedStatement st = conn.prepareStatement("select sum(amount) from billing where no like \'"+no+"%\' and  billing_date like \""+String.valueOf(year)+"%\" ");
            ResultSet rs = st.executeQuery();
            while(rs.next())
                total = rs.getDouble(1);
 
            rs.close();
            st.close();
 
                        return total;
        }finally
        {
            DbConnectionManager.release(conn);
        }
 
 
 

And approximately how many records do you have in that table?
You don't need a while there you can replace that with an if as in

if(rs.next()) {
      total = rs.getDouble(1); 
}
 

[nickyeng]

And approximately how many records do you have in that table?
You don't need a while there you can replace that with an if as in

if(rs.next()) {
      total = rs.getDouble(1); 
}
 

60000 records and keep increasing.

[r035198x]

60000 records and keep increasing.

You did put printlns before and after the sql is executed to make sure that it's the querying that taking up all the memory?
Perhaps you should increase the heap size then (See the JVM thread in this forum).
Isn't there a way of optimizing your query?

[nickyeng]

You did put printlns before and after the sql is executed to make sure that it's the querying that taking up all the memory?
Perhaps you should increase the heap size then (See the JVM thread in this forum).
Isn't there a way of optimizing your query?

i was using the for loop in my JSP to loops Billing object that returns by a method which is simple query like :

select count(*) from table1 where name = 'nick' and year = 'year';
 

that Billing object consist of all(60000+) records, and then loops it and total up the amount.

This BOLD part was the original code i've done.

So i package up project as war file, and run in my server, it gives me OutOfMemoryError: java heap space.

So, boss ask me to change my code so that let it be more simpler and take lesser memory because he dont want increase the java memory(jvm thing).

In the end, i came up with the code i posted in the 1st post.

now, i still getting the same error.
haiz.