刚学完jdbc:现在做个小项目练习一下项目:旅馆定房系统项目分析: 业务逻辑:Roombiz(房间的添加,删除,修改,查找)
数据:Room(房间的数据,如,唯一id号,房间号)问题:我在oracle数据库中建立room房间表,把id设置为主键,并且自动生成,保证唯一就行了,可是老师还用很很多其他的方法来创建id,为什么呢?Room类:
package linshi.hbs.entity;public class Room
{
private int id; private String no; private String type; private String description; public String getDescription()
{
return description;
} public void setDescription(String description)
{
this.description = description;
} public int getId()
{
return id;
} public void setId(int id)
{
this.id = id;
} public String getNo()
{
return no;
} public void setNo(String no)
{
this.no = no;
} public String getType()
{
return type;
} public void setType(String type)
{
this.type = type;
}}Roombiz类: 注意就看添加方法
package linshi.hbs.biz;import java.util.Collection;import linshi.hbs.entity.Room;
import linshi.hbs.util.IdGenerator;
import linshi.hbs.util.IdGeneratorFactory;public class RoomBiz
{
public void add(Room room) throws Exception
{
IdGenerator generator = IdGeneratorFactory.getIdGenerator();
generator.setProperty("sequence", "room_seq");
room.setId(generator.nextId());
}
public void modify(Room room) throws Exception
{
}
public void remove(Room room) throws Exception
{
}
public Collection find(Room room) throws Exception
{
return null;
}
public Room findById(int id) throws Exception
{
return null;
}
}
数据:Room(房间的数据,如,唯一id号,房间号)问题:我在oracle数据库中建立room房间表,把id设置为主键,并且自动生成,保证唯一就行了,可是老师还用很很多其他的方法来创建id,为什么呢?Room类:
package linshi.hbs.entity;public class Room
{
private int id; private String no; private String type; private String description; public String getDescription()
{
return description;
} public void setDescription(String description)
{
this.description = description;
} public int getId()
{
return id;
} public void setId(int id)
{
this.id = id;
} public String getNo()
{
return no;
} public void setNo(String no)
{
this.no = no;
} public String getType()
{
return type;
} public void setType(String type)
{
this.type = type;
}}Roombiz类: 注意就看添加方法
package linshi.hbs.biz;import java.util.Collection;import linshi.hbs.entity.Room;
import linshi.hbs.util.IdGenerator;
import linshi.hbs.util.IdGeneratorFactory;public class RoomBiz
{
public void add(Room room) throws Exception
{
IdGenerator generator = IdGeneratorFactory.getIdGenerator();
generator.setProperty("sequence", "room_seq");
room.setId(generator.nextId());
}
public void modify(Room room) throws Exception
{
}
public void remove(Room room) throws Exception
{
}
public Collection find(Room room) throws Exception
{
return null;
}
public Room findById(int id) throws Exception
{
return null;
}
}
解决方案 »
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