小编sha*_*ira的帖子

ERD(实体关系图)和EERD(增强实体关系图)之间有什么区别？

大家好我有这个代码,但不知道为什么它不起作用!

//in database class 

String query = "SELECT group_name FROM customer ORDER BY group_name"; 
java.sql.PreparedStatement stm = connection.prepareStatement(query); 

rs = stm.executeQuery(query); 

while (rs.next()) { 
String x = rs.getString("group_name"); 
System.out.println(x); 
} 

rs.close(); 
} 


//combo box action 


int group = jcombobox.getSelectedIndex(); 

rg_domain rg = new rg_domain(); 
rg.setGroup(group); 
rg.setPhone_number(phone_no); 

dbconnection db = new dbconnection(); 

db.broadcastmsgservice_sms(rg); 
} 


//domain class 
 private String group;
public void setGroup(String group) { 
this.group = group; 
} 
public String getGroup() { 
return group; 
} 

有人可以帮我吗...