您可以
JAXBElement直接创建一个实例，或者如果您是从XML模式生成的Java模型，请在生成的
ObjectFactory类上使用convience方法。
package org.example.schema;import javax.xml.bind.*;import javax.xml.namespace.QName;public class Demo { public static void main(String[] args) throws Exception { JAXBContext jc = JAXBContext.newInstance("org.example.schema"); Root root = new Root(); QName fooQName = new QName("http://www.example.org/schema", "foo"); JAXBElement<String> fooValue = new JAXBElement<String>(fooQName, String.class, "FOO"); root.setFoo(fooValue); ObjectFactory objectFactory = new ObjectFactory(); JAXBElement<String> barValue = objectFactory.createRootBar("BAR"); root.setBar(barValue); Marshaller marshaller = jc.createMarshaller(); marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true); marshaller.marshal(root, System.out); }}schema.xsd
上面的演示代码基于从以下XML模式生成的Java模型。你会得到一个原因
JAXBElement<String>摆在首位属性是当你有一个既是元素
nillable="true"和
minOccurs="0"。
<?xml version="1.0" encoding="UTF-8"?><schema xmlns="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.example.org/schema" xmlns:tns="http://www.example.org/schema" elementFormDefault="qualified"> <element name="root"> <complexType> <sequence> <element name="foo" type="string" minOccurs="0" nillable="true"/> <element name="bar" type="string" minOccurs="0" nillable="true"/> </sequence> </complexType> </element></schema>
根
以下类是从中生成的，
schema.xsd并且包含与您所问问题类似的属性。
package org.example.schema;import javax.xml.bind.JAXBElement;import javax.xml.bind.annotation.*;@XmlAccessorType(XmlAccessType.FIELD)@XmlType(name = "", propOrder = {"foo","bar"})@XmlRootElement(name = "root")public class Root { @XmlElementRef(name = "foo", namespace = "http://www.example.org/schema", type = JAXBElement.class) protected JAXBElement<String> foo; @XmlElementRef(name = "bar", namespace = "http://www.example.org/schema", type = JAXBElement.class) protected JAXBElement<String> bar; public JAXBElement<String> getFoo() { return foo; } public void setFoo(JAXBElement<String> value) { this.foo = value; } public JAXBElement<String> getBar() { return bar; } public void setBar(JAXBElement<String> value) { this.bar = value; }}对象工厂
以下是生成的
ObjectFactory类，其中包含用于创建实例的便捷方法
JAXBElement。
package org.example.schema;import javax.xml.bind.JAXBElement;import javax.xml.bind.annotation.*;import javax.xml.namespace.QName;@XmlRegistrypublic class ObjectFactory { private final static QName _RootFoo_QNAME = new QName("http://www.example.org/schema", "foo"); private final static QName _RootBar_QNAME = new QName("http://www.example.org/schema", "bar"); public Root createRoot() { return new Root(); } @XmlElementDecl(namespace = "http://www.example.org/schema", name = "foo", scope = Root.class) public JAXBElement<String> createRootFoo(String value) { return new JAXBElement<String>(_RootFoo_QNAME, String.class, Root.class, value); } @XmlElementDecl(namespace = "http://www.example.org/schema", name = "bar", scope = Root.class) public JAXBElement<String> createRootBar(String value) { return new JAXBElement<String>(_RootBar_QNAME, String.class, Root.class, value); }}
