java - Maven 在@XmlAccessorType 上抛出编译错误 "Cannot find symbol"，但我可以找到它

Question

为什么我的 mvn clean install 命令告诉我它找不到符号，而它提示的类似乎显然可用？

我正在构建一个库来处理对 REST API (HP ALM) 的调用。它返回 xml，因此我必须解析结果。

该库已基本完成并可以运行，但现在我想在更大的 gui 应用程序中对其进行测试，因此我需要构建 .jar 并将其安装到我的本地 maven 存储库中。在库的开发过程中没有(相关的)错误。

这是我在运行 mvn clean install 时遇到的错误

[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building rest-qc 1.0
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ rest-qc ---
[INFO] Deleting C:\Data\workspaces\MRPB\workspace\rest-qc\target
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ rest-qc ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] Copying 0 resource
[INFO]
[INFO] --- maven-compiler-plugin:2.3.2:compile (default-compile) @ rest-qc ---
[WARNING] File encoding has not been set, using platform encoding Cp1252, i.e. build is platform dependent!
[INFO] Compiling 27 source files to C:\Data\workspaces\MRPB\workspace\rest-qc\target\classes
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR :
[INFO] -------------------------------------------------------------
[ERROR] \Data\workspaces\MRPB\workspace\rest-qc\src\main\java\infrastructure\Entity.java:[172,2] error: cannot find symbol
[ERROR] \Data\workspaces\MRPB\workspace\rest-qc\src\main\java\infrastructure\Entity.java:[173,2] error: cannot find symbol
[INFO] 2 errors
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.400 s
[INFO] Finished at: 2016-08-26T10:32:32+02:00
[INFO] Final Memory: 10M/123M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.3.2:compile (default-compile) on project rest-qc: Compilation failure: Compilati
on failure:
[ERROR] \Data\workspaces\MRPB\workspace\rest-qc\src\main\java\infrastructure\Entity.java:[172,2] error: cannot find symbol
[ERROR] \Data\workspaces\MRPB\workspace\rest-qc\src\main\java\infrastructure\Entity.java:[173,2] error: cannot find symbol
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException

现在，我了解到编译器插件 2.3.2 可能存在错误，因此我尝试了多个其他版本的插件。这是 3.1 的响应:

[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building rest-qc 1.0
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ rest-qc ---
[INFO] Deleting C:\Data\workspaces\MRPB\workspace\rest-qc\target
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ rest-qc ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] Copying 0 resource
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ rest-qc ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding Cp1252, i.e. build is platform dependent!
[INFO] Compiling 27 source files to C:\Data\workspaces\MRPB\workspace\rest-qc\target\classes
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR :
[INFO] -------------------------------------------------------------
[ERROR] /C:/Data/workspaces/MRPB/workspace/rest-qc/src/main/java/infrastructure/Entity.java:[172,10] cannot find symbol
  symbol:   class XmlAccessorType
  location: class infrastructure.Entity
[ERROR] /C:/Data/workspaces/MRPB/workspace/rest-qc/src/main/java/infrastructure/Entity.java:[173,10] cannot find symbol
  symbol:   class XmlType
  location: class infrastructure.Entity
[INFO] 2 errors
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.668 s
[INFO] Finished at: 2016-08-26T10:32:14+02:00
[INFO] Final Memory: 13M/163M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project rest-qc: Compilation failure: Compilation
 failure:
[ERROR] /C:/Data/workspaces/MRPB/workspace/rest-qc/src/main/java/infrastructure/Entity.java:[172,10] cannot find symbol
[ERROR] symbol:   class XmlAccessorType
[ERROR] location: class infrastructure.Entity
[ERROR] /C:/Data/workspaces/MRPB/workspace/rest-qc/src/main/java/infrastructure/Entity.java:[173,10] cannot find symbol
[ERROR] symbol:   class XmlType
[ERROR] location: class infrastructure.Entity
[ERROR] -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException

它们都给出了几乎相同的错误。 3.1 与 2.3.2 具有相同的行号，但字符索引从 2->10 变化。此外，3.1 具体说明了导致错误的类。 Entity 类是一个标准的生成类，用于解释 REST 调用的结果。所有结果对象都将采用实体格式。

作为引用，这是我的 pom.xml。我已经手动检查了 jaxb-bind 依赖项 jar 以检查相关注释类是否在库中。确实如此。

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>sdc.qualitycenter</groupId>
    <artifactId>rest-qc</artifactId>
    <version>1.0</version>
    <dependencies>
        <dependency>
            <groupId>com.sun.jersey</groupId>
            <artifactId>jersey-bundle</artifactId>
            <version>1.19.1</version>
        </dependency>
        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
            <version>2.1</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>2.2.4</version>
        </dependency>
        <dependency>
            <groupId>joda-time</groupId>
            <artifactId>joda-time</artifactId>
            <version>2.9.4</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.4</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>1.7</source>
                    <target>1.7</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

最后但同样重要的是，实体类(我手动添加了一个 toString 方法)

package infrastructure;

/*

This file was generated by the JavaTM Architecture for XML Binding(JAXB)
Reference Implementation, vhudson-jaxb-ri-2.1-456
See http://www.oracle.com/technetwork/articles/javase/index-140168.html
Any modifications to this file will be lost upon recompilation of the source schema.


This example of an automatically generated class is an example of how one can
generate classes from XSDs via xjc to match jaxb standards.
XSD is a format for describing a class structure
(note: the CLASS not an INSTANCE of the class).
From an XSD one can generate a class java source file.
When compiling this source file, one can "marshal" an actual object instance
from the XML describing the object (this time we are talking about an instance,
not a class).

this process has many advantages, and is a form of serialization that is not
language dependent.
This is the recommended way of working with entities, though we do suggest you
customize your entity class with simpler accessors.


 */

import infrastructure.Entity.Fields.Field;

import javax.xml.bind.annotation.*;

import java.util.ArrayList;
import java.util.List;

/**
 * Java class for anonymous complex type.
 *
 * The following schema fragment specifies the expected content contained within this class.
 *
 * <complexType>
 *   <complexContent>
 *     <restriction base="{http://www.w3.org/2001/XMLSchema}anyType">
 *       <sequence>
 *         <element name="Fields">
 *           <complexType>
 *             <complexContent>
 *               <restriction base=
 *                  "{http://www.w3.org/2001/XMLSchema}anyType">
 *                 <sequence>
 *                   <element name="Field" maxOccurs="unbounded">
 *                     <complexType>
 *                       <complexContent>
 *                         <restriction base=
 *                            "{http://www.w3.org/2001/XMLSchema}anyType">
 *                           <sequence>
 *                             <element name="Value"
 *                               type="{http://www.w3.org/2001/XMLSchema}string"
 *                               maxOccurs="unbounded"/>
 *                           </sequence>
 *                           <attribute name="Name" use="required"
 *                             type="{http://www.w3.org/2001/XMLSchema}string" />
 *                         </restriction>
 *                       </complexContent>
 *                     </complexType>
 *                   </element>
 *                 </sequence>
 *               </restriction>
 *             </complexContent>
 *           </complexType>
 *         </element>
 *       </sequence>
 *       <attribute name="Type" use="required"
 *           type="{http://www.w3.org/2001/XMLSchema}string" />
 *     </restriction>
 *   </complexContent>
 * </complexType>
 *
 *
 */
@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(name = "", propOrder = { "fields" })
@XmlRootElement(name = "Entity")
public class Entity {

    @XmlElement(name = "Fields", required = true)
    protected Entity.Fields fields;
    @XmlAttribute(name = "Type", required = true)
    protected String type;


    public Entity(Entity entity) {
        type = entity.getType();
        fields = new Entity.Fields(entity.getFields());
    }

    public Entity() {}

    /**
     * Gets the value of the fields property.
     *
     * @return possible object is {@link Entity.Fields }
     *
     */
    public Entity.Fields getFields() {
        return fields;
    }

    /**
     * Sets the value of the fields property.
     *
     * @param value
     *            allowed object is {@link Entity.Fields }
     *
     */
    public void setFields(Entity.Fields value) {
        this.fields = value;
    }

    /**
     * Gets the value of the type property.
     *
     * @return possible object is {@link String }
     *
     */
    public String getType() {
        return type;
    }

    /**
     * Sets the value of the type property.
     *
     * @param value
     *            allowed object is {@link String }
     *
     */
    public void setType(String value) {
        this.type = value;
    }

    /**
     * Java class for anonymous complex type.
     *
     * The following schema fragment specifies the expected content contained within this class.
     *
     * <complexType>
     *   <complexContent>
     *     <restriction base="{http://www.w3.org/2001/XMLSchema}anyType">
     *       <sequence>
     *         <element name="Field" maxOccurs="unbounded">
     *           <complexType>
     *             <complexContent>
     *               <restriction base=
     *                  "{http://www.w3.org/2001/XMLSchema}anyType">
     *                 <sequence>
     *                   <element name="Value"
     *                     type="{http://www.w3.org/2001/XMLSchema}string"
     *                       maxOccurs="unbounded"/>
     *                 </sequence>
     *                 <attribute name="Name" use="required"
     *                   type="{http://www.w3.org/2001/XMLSchema}string" />
     *               </restriction>
     *             </complexContent>
     *           </complexType>
     *         </element>
     *       </sequence>
     *     </restriction>
     *   </complexContent>
     * </complexType>
     *
     *
     */
    @XmlAccessorType(XmlAccessType.FIELD)
    @XmlType(name = "", propOrder = { "field" })
    public static class Fields {

        @XmlElement(name = "Field", required = true)
        protected List<Field> field;


        public Fields(Fields fields) {
            field = new ArrayList<Field>(fields.getField());
        }


        public Fields() {}

        /**
         * Gets the value of the field property.
         *

         * This accessor method returns a reference to the live list, not a snapshot.
         * Therefore any  modification you make to the returned list will be present
         * inside the JAXB object.
         * This is why there is no set method for the field property.
         *
         * For example, to add a new item, do as follows:
         *
         *  getField().add(newItem); 
         *
         * Objects of the following type(s) are allowed in the list {@link Entity.Fields.Field }
         *
         *
         */
        public List<Field> getField() {
            if (field == null) {
                field = new ArrayList<Field>();
            }
            return this.field;
        }

        /**
         * Java class for anonymous complex type.
         *
         * The following schema fragment specifies the expected content contained
         * within this class.
         *
         * <complexType>
         *   <complexContent>
         *     <restriction base="{http://www.w3.org/2001/XMLSchema}anyType">
         *       <sequence>
         *         <element name="Value"
         *            type="{http://www.w3.org/2001/XMLSchema}string"
         *            maxOccurs="unbounded"/>
         *       </sequence>
         *       <attribute name="Name" use="required"
         *          type="{http://www.w3.org/2001/XMLSchema}string" />
         *     </restriction>
         *   </complexContent>
         * </complexType>
         *
         */
        @XmlAccessorType(XmlAccessType.FIELD)
        @XmlType(name = "", propOrder = { "value" })
        public static class Field {

            @XmlElement(name = "Value", required = true)
            protected List<String> value;
            @XmlAttribute(name = "Name", required = true)
            protected String name;

            /**
             * Gets the value of the value property.
             *
             * This accessor method returns a reference to the live list, not a snapshot.
             * Therefore, any modification you make to the returned list will be present
             * inside the JAXB object. This is why there is no set method
             * for the value property.
             *
             * For example, to add a new item, do as follows:
             *
             * getValue().add(newItem);
             *

             * Objects of the following type(s) are allowed in the list {@link String }
             *
             *
             */
            public List<String> getValue() {
                if (value == null) {
                    value = new ArrayList<String>();
                }
                return this.value;
            }

            /**
             * Gets the value of the name property.
             *
             * @return possible object is {@link String }
             *
             */
            public String getName() {
                return name;
            }

            /**
             * Sets the value of the name property.
             *
             * @param value
             *            allowed object is {@link String }
             *
             */
            public void setName(String value) {
                this.name = value;
            }

        }

    }

    public String toString(){
        StringBuilder sb = new StringBuilder();
        sb.append("############## NEW ENTITY ################\n");
        List<Field> fields = this.getFields().getField();
        for (Field field : fields) {
            sb.append(field.getName() + " : " + field.getValue()+"\n");
        }
        return sb.toString();
    }
}

Answer 1

我假设你定义为依赖的版本

<dependency>
  <groupId>javax.xml.bind</groupId>
  <artifactId>jaxb-api</artifactId>
  <version>2.1</version>
</dependency>

太老了。所以我建议使用 newer version like

<dependency>
    <groupId>javax.xml.bind</groupId>
    <artifactId>jaxb-api</artifactId>
    <version>2.2.12</version>
</dependency>