Duvidas sobre commit rollback

try{
			
	conn = getConnection();
			
			
	stmt = conn.prepareStatement("insert into endereco (rua,bairro) values(?,?)");
		
			
	stmt.setString(1, end.getRua());
	stmt.setString(2, end.getBairro());		
			
	stmt.execute();

	stmt.close(); // tenho duvidas se coloco isto aqui

	stmt = conn.prepareStatement("insert into filial (razao,fantasia) values(?,?)");
	
        stmt.execute();	
			
	stmt.setString(1, filial.getRazao());
	stmt.setString(2, filial.getFantasia());	
			
	conn.commit();
					
	}catch(Exception e){

                conn.rollback();

		e.printStackTrace();
	}
		
	finally{
		try {
			stmt.close();
			conn.close();
			conn = null;				
			stmt = null;
								
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

commit

public void commit()
            throws SQLException

    Makes all changes made since the previous commit/rollback permanent and releases any database locks currently held by the Connection. This method should be used only when auto-commit mode has been disabled.

    Throws:
        SQLException - if a database access error occurs
    See Also:
        setAutoCommit(boolean)

rollback

public void rollback()
              throws SQLException

    Drops all changes made since the previous commit/rollback and releases any database locks currently held by this Connection. This method should be used only when auto- commit has been disabled.

    Throws:
        SQLException - if a database access error occurs
    See Also:
        setAutoCommit(boolean)