sql java中使用rs游标选择返回问题

public boolean Check_reg_name(String name){
try{
try{
Class.forName("com.mysql.jdbc.Driver");
}
catch(java.lang.ClassNotFoundException e){
System.out.println("ClassNotFoundException:");
System.out.println(e.getMessage());
}
con = DriverManager.getConnection(url);
stmt = con.createStatement();
rs = stmt.executeQuery(" Select * From userinfo Where username='"+name+"'");
con.close();
}
catch(SQLException ex){
ex.printStackTrace();
if(ex!=null){
System.out.println("数据库异常被捕获");
System.out.println(ex.getSQLState());
System.out.println(ex.getMessage());
System.out.println(ex.getErrorCode());
}
}
if(rs==null){
return(true);
}
else{
return(false);
}
}
这是我本来写的程序 但是有错误 本程

public boolean Check_reg_name(String name){
try{
try{
Class.forName("com.mysql.jdbc.Driver");
}
catch(java.lang.ClassNotFoundException e){
System.out.println("ClassNotFoundException:");
System.out.println(e.getMessage());
}
con = DriverManager.getConnection(url);
stmt = con.createStatement();
rs = stmt.executeQuery(" Select * From userinfo Where username='"+name+"'");
if(!rs.next()){
rs.close();
con.close();
return false
}
rs.close();
con.close();
return true;
}

catch(SQLException ex){
ex.printStackTrace();
if(ex!=null){
System.out.println("数据库异常被捕获");
System.out.println(ex.getSQLState());
System.out.println(ex.getMessage());
System.out.println(ex.getErrorCode());
}
}