XMLDecoder >> java.lang.IllegalArgumentException: 不支持的元素
XMLDecoder >> java.lang.IllegalArgumentException: Unsupported element
收到此错误
java.lang.IllegalArgumentException: Unsupported element: net
来自这个例子xml 文件
<?xml version="1.0" encoding="UTF-8"?>
<net>
<node label="A">
...
</node>
<node label="B">
...
</node>
<node label="C">
...
</node>
</net>
这些 java 代码行
...
FileInputStream file = new FileInputStream("example.xml");
XMLDecoder decoder = new XMLDecoder(file);
Object decodedResistors = (Object) decoder.readObject();
file.close();
...
不要使用 java.beans.XMLDecoder
反序列化自定义 XML
负载。它不是为此而设计的。阅读文章 Long Term Persistence of JavaBeans Components: XML Schema。它包含一些示例 XML
有效负载,可以通过 XMLDecoder
:
反序列化
<?xml version="1.0" encoding="UTF-8" ?>
<java version="1.4.0" class="java.beans.XMLDecoder">
<void id="myController" property="owner"/>
<object class="javax.swing.JButton">
<void method="addActionListener">
<object class="java.beans.EventHandler" method="create">
<class>java.awt.event.ActionListener</class>
<object idref="myController"/>
<string>doIt</string>
</object>
</void>
</object>
</java>
如果您需要反序列化自定义 XML
,请使用 JAXB
或 Jackson XML
。您需要创建一个带有 JAXB
注释的 POJO
模型:
@XmlRootElement(name = "net")
@XmlAccessorType(XmlAccessType.FIELD)
class Net {
@XmlElement(name = "node")
private List<Node> nodes;
// getters, setters, toString
}
@XmlAccessorType(XmlAccessType.FIELD)
class Node {
@XmlAttribute
private String label;
// getters, setters, toString
}
用法示例:
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import java.io.File;
import java.util.List;
public class JaxbApp {
public static void main(String[] args) throws Exception {
File xmlFile = new File("./resource/test.xml").getAbsoluteFile();
JAXBContext jaxbContext = JAXBContext.newInstance(Net.class);
Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
Object net = unmarshaller.unmarshal(xmlFile);
System.out.println(net);
}
}
打印:
Net{nodes=[Node{label='A'}, Node{label='B'}, Node{label='C'}]}
另请参阅:
收到此错误
java.lang.IllegalArgumentException: Unsupported element: net
来自这个例子xml 文件
<?xml version="1.0" encoding="UTF-8"?>
<net>
<node label="A">
...
</node>
<node label="B">
...
</node>
<node label="C">
...
</node>
</net>
这些 java 代码行
...
FileInputStream file = new FileInputStream("example.xml");
XMLDecoder decoder = new XMLDecoder(file);
Object decodedResistors = (Object) decoder.readObject();
file.close();
...
不要使用 java.beans.XMLDecoder
反序列化自定义 XML
负载。它不是为此而设计的。阅读文章 Long Term Persistence of JavaBeans Components: XML Schema。它包含一些示例 XML
有效负载,可以通过 XMLDecoder
:
<?xml version="1.0" encoding="UTF-8" ?>
<java version="1.4.0" class="java.beans.XMLDecoder">
<void id="myController" property="owner"/>
<object class="javax.swing.JButton">
<void method="addActionListener">
<object class="java.beans.EventHandler" method="create">
<class>java.awt.event.ActionListener</class>
<object idref="myController"/>
<string>doIt</string>
</object>
</void>
</object>
</java>
如果您需要反序列化自定义 XML
,请使用 JAXB
或 Jackson XML
。您需要创建一个带有 JAXB
注释的 POJO
模型:
@XmlRootElement(name = "net")
@XmlAccessorType(XmlAccessType.FIELD)
class Net {
@XmlElement(name = "node")
private List<Node> nodes;
// getters, setters, toString
}
@XmlAccessorType(XmlAccessType.FIELD)
class Node {
@XmlAttribute
private String label;
// getters, setters, toString
}
用法示例:
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import java.io.File;
import java.util.List;
public class JaxbApp {
public static void main(String[] args) throws Exception {
File xmlFile = new File("./resource/test.xml").getAbsoluteFile();
JAXBContext jaxbContext = JAXBContext.newInstance(Net.class);
Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
Object net = unmarshaller.unmarshal(xmlFile);
System.out.println(net);
}
}
打印:
Net{nodes=[Node{label='A'}, Node{label='B'}, Node{label='C'}]}
另请参阅: