原因：java.lang.ClassNotFoundException:com.sun.xml.bind.v2.model.annotation.AnnotationReader

你们可能认为下面的问题很简单，但我不知道我做错了什么。我觉得我添加了必需的依赖项。不是吗

谁能告诉我这里出了什么问题吗

Exception in thread "main" java.lang.NoClassDefFoundError: com/sun/xml/bind/v2/model/annotation/AnnotationReader
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
    at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at java.lang.Class.getDeclaredMethods0(Native Method)
    at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)
    at java.lang.Class.privateGetMethodRecursive(Class.java:3048)
    at java.lang.Class.getMethod0(Class.java:3018)
    at java.lang.Class.getMethod(Class.java:1784)
    at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:242)
    at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:234)
    at javax.xml.bind.ContextFinder.find(ContextFinder.java:441)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:641)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:584)
    at com.misc.common.ReadXMLFileJaxb.main(ReadXMLFileJaxb.java:14)
Caused by: java.lang.ClassNotFoundException: com.sun.xml.bind.v2.model.annotation.AnnotationReader
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 23 more

Book.java

@XmlRootElement
@XmlAccessorType(XmlAccessType.FIELD)
public class Book {
    @XmlAttribute
    private String firstName;
    @XmlElement
    private String lastName;
    @XmlElement
    private String age;


    public String getFirstName() {
        return firstName;
    }
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }
    public String getLastName() {
        return lastName;
    }
    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
    public String getAge() {
        return age;
    }
    public void setAge(String age) {
        this.age = age;
    }
    @Override
    public String toString() {
        return "Book [firstName=" + firstName + ", lastName=" + lastName+ ", age=" + age + "]";
    }
}

@XmlRootElement(name="book")
@XmlAccessorType(XmlAccessType.FIELD)
public class Book {
    private List<Person> person = new ArrayList<Person>();

    public List<Person> getPerson() {
        return person;
    }

    public void setPerson(List<Person> person) {
        this.person = person;
    }
}

ReadXMLFileJaxb.java

public class ReadXMLFileJaxb {
    public static void main(String[] args) {
        File file = new File(ReadXMLFileDOM.class.getClassLoader().getResource("book.xml").getFile());

        try {
            JAXBContext context = JAXBContext.newInstance(Book.class);
            Unmarshaller unmarshaller = context.createUnmarshaller();
            Book book = (Book) unmarshaller.unmarshal(file);
            System.out.println(book.toString());
        } catch (JAXBException e) {
            System.out.println(e.getMessage());
        }
    }
}

public class ReadXMLFileJaxb {
    public static void main(String[] args) {
        File file = new File(ReadXMLFileDOM.class.getClassLoader().getResource("book.xml").getFile());

        try {
            JAXBContext context = JAXBContext.newInstance(Book.class);
            Unmarshaller unmarshaller = context.createUnmarshaller();
            Book book = (Book) unmarshaller.unmarshal(file);
            System.out.println(book.getPerson().size());

            for (int i = 0; i < book.getPerson().size(); i++) {
                System.out.println("------------");
                System.out.println(book.getPerson().get(i).getFirst());
                System.out.println(book.getPerson().get(i).getLast());
                System.out.println(book.getPerson().get(i).getAge());
            }

        } catch (JAXBException e) {
            System.out.println(e.getMessage());
        }
    }
}

mybook.xml

<?xml version="1.0"?>
<book>
    <person>
        <first>Kiran</first>
        <last>Pai</last>
        <age>22</age>
    </person>
    <person>
        <first>Bill</first>
        <last>Gates</last>
        <age>46</age>
    </person>
    <person>
        <first>Steve</first>
        <last>Jobs</last>
        <age>40</age>
    </person>
</book>

基兰
派

pom.xml

<properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <!-- JAXB -->
        <dependency>
            <groupId>com.sun.xml.bind</groupId>
            <artifactId>jaxb-impl</artifactId>
            <version>2.2.11</version>
        </dependency>
        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
            <version>2.2.12</version>
        </dependency>
    </dependencies>


UTF-8
1.8
com.sun.xml.bind
jaxb impl
2.2.11
javax.xml.bind
jaxb api
2.2.12
您似乎在IDE中运行它。出于一些奇怪的原因，尽管JAXB类包含在JRE的rt.jar中

➜  lib jar tvf rt.jar| grep AnnotationReader
  4199 Fri Jan 29 15:35:18 PST 2016 com/sun/xml/internal/bind/v2/model/annotation/AbstractInlineAnnotationReaderImpl.class
  3140 Fri Jan 29 15:35:14 PST 2016 com/sun/xml/internal/bind/v2/model/annotation/AnnotationReader.class
   442 Fri Jan 29 15:35:14 PST 2016 com/sun/xml/internal/bind/v2/model/annotation/RuntimeAnnotationReader.class
  9846 Fri Jan 29 15:35:22 PST 2016 com/sun/xml/internal/bind/v2/model/annotation/RuntimeInlineAnnotationReader.class
  1217 Fri Jan 29 15:35:26 PST 2016 com/sun/xml/internal/ws/model/ReflectAnnotationReader$1.class
  1332 Fri Jan 29 15:35:26 PST 2016 com/sun/xml/internal/ws/model/ReflectAnnotationReader$2.class
  1278 Fri Jan 29 15:35:26 PST 2016 com/sun/xml/internal/ws/model/ReflectAnnotationReader$3.class
  1166 Fri Jan 29 15:35:26 PST 2016 com/sun/xml/internal/ws/model/ReflectAnnotationReader$4.class
  3563 Fri Jan 29 15:35:26 PST 2016 com/sun/xml/internal/ws/model/ReflectAnnotationReader.class

它们在运行时不适用于您的应用程序

但是，如果我以这种方式运行应用程序：

➜  target java -cp ./classes com.misc.common.ReadXMLFileJaxb
Book [firstName=null, lastName=Blo, age=33]

i、 e.从使用标准Maven结构的命令行，它看起来确实在运行

我认为您的book.xml有些错误。它包含一个嵌入的
person
元素，而Book.java不包含。您可能需要修复此问题。
根据链接：，您只需使用以下maven依赖项：

<dependency>
    <groupId>com.sun.xml.bind</groupId>
    <artifactId>jaxb-impl</artifactId>
    <version>2.2.11</version>
</dependency>

<dependency>
    <groupId>com.sun.xml.bind</groupId>
    <artifactId>jaxb-core</artifactId>
    <version>2.2.11</version>
</dependency>

Book.java

@XmlRootElement
@XmlAccessorType(XmlAccessType.FIELD)
public class Book {
    @XmlAttribute
    private String firstName;
    @XmlElement
    private String lastName;
    @XmlElement
    private String age;


    public String getFirstName() {
        return firstName;
    }
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }
    public String getLastName() {
        return lastName;
    }
    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
    public String getAge() {
        return age;
    }
    public void setAge(String age) {
        this.age = age;
    }
    @Override
    public String toString() {
        return "Book [firstName=" + firstName + ", lastName=" + lastName+ ", age=" + age + "]";
    }
}

@XmlRootElement(name="book")
@XmlAccessorType(XmlAccessType.FIELD)
public class Book {
    private List<Person> person = new ArrayList<Person>();

    public List<Person> getPerson() {
        return person;
    }

    public void setPerson(List<Person> person) {
        this.person = person;
    }
}

虽然这个问题已经很老了，但仍然有答案。根本原因是com.sun.xml.bind现在已经过时。jaxb是jaxb API的最新参考实现。使用以下JAXB RI maven依赖项可以解决这个问题

    <dependency>
        <groupId>org.glassfish.jaxb</groupId>
        <artifactId>jaxb-runtime</artifactId>
        <version>2.2.11</version>
    </dependency>


org.glassfish.jaxb
jaxb运行时
2.2.11
我发现最好的解决方案是使用maven-jaxb2-plugin，那么您需要的唯一依赖性就是：

    <!-- https://mvnrepository.com/artifact/org.jvnet.jaxb2.maven2/maven-jaxb2-plugin -->
    <dependency>
        <groupId>org.jvnet.jaxb2.maven2</groupId>
        <artifactId>maven-jaxb2-plugin</artifactId>
        <version>0.14.0</version>
    </dependency>


org.jvnet.jaxb2.maven2
maven-jaxb2-plugin
0.14.0
通过在pom中添加这两个依赖项来解决此错误

    <dependency>
        <groupId>com.sun.xml.bind</groupId>
        <artifactId>jaxb-impl</artifactId>
        <version>2.2.11</version>
    </dependency>
    <dependency>
        <groupId>com.sun.xml.bind</groupId>
        <artifactId>jaxb-core</artifactId>
        <version>2.2.11</version>
    </dependency>


com.sun.xml.bind
jaxb impl
2.2.11
com.sun.xml.bind
jaxb内核
2.2.11
我认为情况就是这样，我添加了它，但仍然存在问题i必须切换到运行时和核心的2.3.0工件来修复问题i实际上对我有效：
com.sun.activation javax.activation 1.2.0 org.glassfish.jaxb jaxb runtime 2.3.0
@Ignaciolucatero只有您的组合有效，谢谢！！！（java10，spring boot 2.0.x）不需要
jaxb核心
和
jaxb impl
，
jaxb核心
自动添加
jaxb impl
。仅供参考：jaxb核心不再是com.sun.xml.bind的一部分。我得到了同样的错误，并使用com.sun.xml.bind中的jaxb xjc版本2.1.7进行了修复。我尝试了上述所有解决方案，但最后只有这个解决方案对我来说运行良好。