【发布时间】：2015-03-31 23:43:57
【问题描述】：
我有这个用于操作这个领域车辆的类集合
这是我的问题：我需要将数据保存（通过解析）到 XML 文件。为此，我必须创建一个 XML Schema (XSD)，但在继承和接口方面遇到了困难。
首先，似乎有必要快速解释我的课程：
Vehicle 类是一个抽象类，包含基本属性：
public abstract class Vehicle implements Serializable {
public enum Stato {
DISPONIBILE,
NON_DISPONIBILE
}
private String plate; // targa
private String mark; // Marca, Casa Produttrice
private String model; // Modello
private String trim; // Trim
private float capacity; // capacità di carico
// ... other...
private Stato stato; // Stato del veicolo
private String allestimento;
public Vehicle(){}
public Vehicle(String plate) {
this.plate=plate;
}
// Get&Set methods
// ...
}
现在，例如，汽车：
public class Car extends Vehicle implements DrivingPart {
public Car();
public Car(String plate) {
super(plate);
}
}
...和TrailerTruck：
public class TrailerTruck extends Vehicle {
// TRAILER TRUCK: autocarro
// Driving Part: Car, Van, Truck
// Driven part: Trailer (always)
String plateFront;
String plateTrailer;
DrivingPart drivingVehicle;
Trailer trailerVehicle;
public TrailerTruck(DrivingPart drivingVehicle, Trailer trailerVehicle) {
plateFront=drivingVehicle.getPlate();
plateTrailer=trailerVehicle.getPlate();
setPlate(plateFront+" - "+plateTrailer);
this.drivingVehicle=drivingVehicle;
this.trailerVehicle=trailerVehicle;
}
@Override
public String getAllestimento() {
return drivingVehicle.getAllestimento()
+", "+trailerVehicle.getAllestimento();
}
// ...
}
好的，这个功能很好。我可以轻松地创建对象 Vehicle：
Vehicle car = new Car("AAA1");
car.setMark("Peugeot");
car.setModel("206");
car.setStato(Stato.DISPONIBILE);
//...
Vehicle truck = new Truck("AAA2");
truck.setMark("Scania");
//...
Vehicle trailer = new Trailer("TTT1");
trailer.setMark("Menci");
//...
Vehicle tt1 = new TrailerTruck((Truck) truck, (Trailer) trailer);
//...
插图结束。对不起，如果我已经住了。
编辑
这是我的解决方案尝试。
ShipperXMLSchema.xsd：
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<xs:schema version="1.0" xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="Fleet" type="FleetType"/>
<xs:complexType name="FleetType">
<xs:choice maxOccurs="unbounded">
<xs:element name="Car" type="CarType"/>
<xs:element name="Van" type="VanType"/>
<xs:element name="Truck" type="TruckType"/>
<xs:element name="Trailer" type="TrailerType"/>
<xs:element name="RoadTractor" type="RoadTractorType"/>
<xs:element name="SemiTrailer" type="SemiTrailerType"/>
<xs:element name="TrailerTruck" type="TrailerTruckType"/>
<xs:element name="SemiTrailerTruck" type="SemiTrailerTruckType"/>
</xs:choice>
<xs:attribute name="shipperName" type="xs:string"/>
</xs:complexType>
<xs:complexType name="VehicleType" abstract="true">
<xs:sequence>
<xs:element name="plate" type="xs:string" minOccurs="1" />
<xs:element name="mark" type="xs:string" minOccurs="0" />
<xs:element name="model" type="xs:string" minOccurs="1" />
<xs:element name="trim" type="xs:string" />
<xs:element name="allestimento" type="xs:string" minOccurs="0" />
<xs:element name="stato" type="State"/>
<xs:element name="carryingCapacity" type="xs:float" minOccurs="0" />
<xs:element name="ptt" type="xs:float" minOccurs="0" />
<xs:element name="weight" type="xs:float" minOccurs="0" />
<xs:element name="volume" type="xs:float" minOccurs="0" />
<xs:element name="length" type="xs:float" minOccurs="0" />
<xs:element name="height" type="xs:float" minOccurs="0" />
<xs:element name="width" type="xs:float" minOccurs="0" />
<xs:element name="locazioneAttuale" type="xs:string" minOccurs="0" />
</xs:sequence>
<xs:attribute name="id" type="xs:string"/>
</xs:complexType>
<!-- Definitions: tipi Car, Van, Truck, Trailer, RoadTractor, SemiTrailer -->
<xs:complexType name="CarType">
<xs:complexContent>
<xs:extension base="VehicleType"/>
</xs:complexContent>
</xs:complexType>
<xs:complexType name="VanType">
<xs:complexContent>
<xs:extension base="VehicleType"/>
</xs:complexContent>
</xs:complexType>
<xs:complexType name="TruckType">
<xs:complexContent>
<xs:extension base="VehicleType"/>
</xs:complexContent>
</xs:complexType>
<xs:complexType name="TrailerType">
<xs:complexContent>
<xs:extension base="VehicleType"/>
</xs:complexContent>
</xs:complexType>
<xs:complexType name="RoadTractorType">
<xs:complexContent>
<xs:extension base="VehicleType"/>
</xs:complexContent>
</xs:complexType>
<xs:complexType name="SemiTrailerType">
<xs:complexContent>
<xs:extension base="VehicleType"/>
</xs:complexContent>
</xs:complexType>
<!-- Definizione tipo TrailerTruck (autotreno) -->
<xs:group name="DrivingPart">
<xs:choice>
<xs:element name="Car" type="CarType"/>
<xs:element name="Van" type="VanType"/>
<xs:element name="Truck" type="TruckType"/>
</xs:choice>
</xs:group>
<xs:complexType name="TrailerTruckType">
<xs:sequence>
<xs:group ref="DrivingPart"/>
<xs:element name="Trailer" type="TrailerType" minOccurs="1" maxOccurs="1"/>
</xs:sequence>
</xs:complexType>
<!-- Definition: SemiTrailerTruck -->
<xs:complexType name="SemiTrailerTruckType" >
<xs:sequence>
<xs:element name="RoadTractor" type="RoadTractorType" minOccurs="1" maxOccurs="1"/>
<xs:element name="SemiTrailer" type="SemiTrailerType" minOccurs="1" maxOccurs="1"/>
</xs:sequence>
</xs:complexType>
<!-- Others... -->
<xs:simpleType name="State">
<xs:restriction base="xs:string">
<xs:enumeration value="DISPONIBILE"/>
<xs:enumeration value="NON_DISPONIBILE"/>
</xs:restriction>
</xs:simpleType>
</xs:schema>
如果托运人有车队。
Shipper1.xml：
<?xml version="1.0" encoding="UTF-8"?>
<Fleet shipperName="Shipper1"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="VehicleXMLSchema.xsd">
<Car id="c1">
<plate>AAA</plate>
<mark>Peugeot</mark>
<model>206</model>
<trim></trim>
<allestimento></allestimento>
<stato>DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>2</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Bari</locazioneAttuale>
</Car>
<Car>
<plate>BBB</plate>
<mark>Peugeot</mark>
<model>206</model>
<trim></trim>
<allestimento></allestimento>
<stato>DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>2</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Bari</locazioneAttuale>
</Car>
<Van>
<plate>CCC</plate>
<mark>Volvo</mark>
<model></model>
<trim></trim>
<allestimento>frigorifero</allestimento>
<stato>DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>3</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Barletta</locazioneAttuale>
</Van>
<Truck id="1">
<plate>DDD</plate>
<mark>Scania</mark>
<model></model>
<trim></trim>
<allestimento>Frigo</allestimento>
<stato>DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>5</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Andria</locazioneAttuale>
</Truck>
<Trailer id="t1">
<plate>EEE</plate>
<mark>Scania</mark>
<model></model>
<trim></trim>
<allestimento>Frigo</allestimento>
<stato>NON_DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>5</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Andria</locazioneAttuale>
</Trailer>
<RoadTractor>
<plate>FFF</plate>
<mark>Scania</mark>
<model></model>
<trim></trim>
<allestimento>Frigo</allestimento>
<stato>NON_DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>5</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Andria</locazioneAttuale>
</RoadTractor>
<SemiTrailer>
<plate>GGG</plate>
<mark>Scania</mark>
<model></model>
<trim></trim>
<allestimento>Frigo</allestimento>
<stato>NON_DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>5</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Andria</locazioneAttuale>
</SemiTrailer>
<TrailerTruck>
<Car id="c1">
<plate>AAA</plate>
<mark>Peugeot</mark>
<model>206</model>
<trim></trim>
<allestimento></allestimento>
<stato>DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>2</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Bari</locazioneAttuale>
</Car>
<Trailer>
<plate>EEE</plate>
<mark>Scania</mark>
<model></model>
<trim></trim>
<allestimento>Frigo</allestimento>
<stato>NON_DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>5</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Andria</locazioneAttuale>
</Trailer>
</TrailerTruck>
<SemiTrailerTruck>
<RoadTractor>
<plate>STT1</plate>
<mark>Scania</mark>
<model></model>
<trim></trim>
<allestimento>Frigo</allestimento>
<stato>NON_DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>5</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Andria</locazioneAttuale>
</RoadTractor>
<SemiTrailer>
<plate>ST2</plate>
<mark>Scania</mark>
<model></model>
<trim></trim>
<allestimento>Frigo</allestimento>
<stato>NON_DISPONIBILE</stato>
<carryingCapacity>0.0</carryingCapacity>
<ptt>5</ptt>
<weight>0.0</weight>
<volume>0.0</volume>
<length>0.0</length>
<height>0.0</height>
<width>0.0</width>
<locazioneAttuale>Andria</locazioneAttuale>
</SemiTrailer>
</SemiTrailerTruck>
</Fleet>
通过这个实现，我可以在 Java 中操作 Car、Van、Truck、Trailer、RoadTractor 和 SemiTrailer 类......但不能操作复杂的 TrailerTruck 和 SemiTrailerTruck 类。 我需要一个包含继承和接口的不同 XSD。但我不知道怎么做。
【问题讨论】：
-
你试过using Google吗？
-
@BoristheSpider 我试过了，但我发现了问题。为什么要重新发明轮子？无论如何，我用解决方案编辑了我的问题，但还是不行。
-
你似乎有一个硬编码的
String type而不是 XML 继承，就像我给你的链接一样。您需要按照链接中的说明使用xs:extension。 XML 中没有“接口”的概念，因为它是数据描述符而不是行为 - 但您应该能够轻松地为每个具体类型定义一个类型并让 JAXB 处理它。 -
你看我的编辑...你会改变什么？
-
看起来好多了，有什么问题？
标签： java xml inheritance xsd xml-parsing