Java解析XML之 Digester的一个小例子

XML文档

<? xml version="1.0" encoding="UTF-8" ?>
<! DOCTYPE po SYSTEM "src/sample.dtd" >
< po  id ="po121"  submitted ="2001-10-05"
    xmlns ="http://www.youkuaiyun.com" >
     < billTo  id ="addr-1" >
         < company > The Redzero Cop. </ company >
         < street > Jianguo Road 1ST </ street >
         < street > Building 1 </ street >
         < city > Haidian </ city >
         < state > Beijing </ state >
         < postalCode > 100071 </ postalCode >
     </ billTo >
     < shipTo  href ="addr-1" />
     < order >
         < item  sku ="o318-BP"  quantity ="5" >
             < description > J2EE programmic </ description >
         </ item >
         < item  sku ="o947-TI"  quantity ="12" >
             < description > Java WEB Service </ description >
         </ item >
         < item  sku ="o008-PR"  quantity ="133" >
             < description > C++ develop </ description >
         </ item >
     </ order >
</ po >

 Java对象树定义

// 根节点，表示一个订单Po
public   class  Po
... {
    private String id;
    private String submitted;
    private BillTo billTo;
    private ShipTo shipTo;
    private Order order;
    public BillTo getBillTo()
    ...{
        return billTo;
    }
    public void setBillTo(BillTo billTo)
    ...{
        this.billTo = billTo;
    }
    public Order getOrder()
    ...{
        return order;
    }
    public void setOrder(Order order)
    ...{
        this.order = order;
    }
    public ShipTo getShipTo()
    ...{
        return shipTo;
    }
    public void setShipTo(ShipTo shipTo)
    ...{
        this.shipTo = shipTo;
    }
    public String getId()
    ...{
        return id;
    }
    public void setId(String id)
    ...{
        this.id = id;
    }
    public String getSubmitted()
    ...{
        return submitted;
    }
    public void setSubmitted(String submitted)
    ...{
        this.submitted = submitted;
    }    
}
// Po的子节点，标识送货地址，对应<po><billTo>
public   class  BillTo  extends  Address
... {
    private String id;

    public String getId()
    ...{
        return id;
    }

    public void setId(String id)
    ...{
        this.id = id;
    }    
}

public   class  ShipTo  extends  Address
... {
    private String href;

    public String getHref()
    ...{
        return href;
    }

    public void setHref(String href)
    ...{
        this.href = href;
    }
    
}
public   class  Address
... {
    private String company;
    private String city;
    private String state;
    private String postalCode;
    private ArrayList streets  = new ArrayList();
    
    public void addStreet(String street)...{
        this.streets.add(street);
    }
    public String getCity()
    ...{
        return city;
    }
    public void setCity(String city)
    ...{
        this.city = city;
    }
    public String getCompany()
    ...{
        return company;
    }
    public void setCompany(String company)
    ...{
        this.company = company;
    }
    public String getPostalCode()
    ...{
        return postalCode;
    }
    public void setPostalCode(String postalCode)
    ...{
        this.postalCode = postalCode;
    }
    public String getState()
    ...{
        return state;
    }
    public void setState(String state)
    ...{
        this.state = state;
    }