Maven Guava 缺少方法 Sets.symmetricDifference

Question

我有一个很奇怪的问题。我将以下依赖项添加到我的 pom.xml

<dependency>
    <groupId>com.google.guava</groupId>
    <artifactId>guava</artifactId>
    <version>31.0.1-jre</version>
</dependency>

当我尝试调用时编写以下代码：

import com.google.common.collect.Sets;

Sets.symmetricDifference(currentSet, referencedSet);

我的编译器说：无法在 'Sets'

中解析方法 'symmetricDifference'

但是我知道这个方法存在，我什至在google的repository

中找到了它

有谁知道为什么会发生这种情况？我也尝试了不同的番石榴版本，但似乎没有任何帮助。

编辑执行 mvn install 时的错误信息：

[ERROR] COMPILATION ERROR : 
[INFO] -------------------------------------------------------------
[ERROR] /C:/somePath/backend/src/main/java/someOtherPath/service/DataVerificationServiceImpl.java:[58,76] cannot find symbol
  symbol:   method symmetricDifference(java.util.Set<org.springframework.data.util.Pair<java.time.ZonedDateTime,java.time.ZonedDateTime>>,java.util.Set<org.springframework.data.util.Pair<java.time.ZonedDateTime,java.time.ZonedDateTime>>)
  location: class com.google.common.collect.Sets

编辑 2：

满pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.4.5</version>
    </parent>
    <artifactId>my_project</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>My project</name>
    <description>My Project Description</description>
    <properties>
        <java.version>11</java.version>
        <keycloak.version>15.0.0</keycloak.version>
    </properties>
    <dependencies>

        <!-- Spring boot -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.keycloak</groupId>
            <artifactId>keycloak-spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-boot-starter</artifactId>
            <version>3.0.0</version>
        </dependency>

        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct-processor</artifactId>
            <version>1.4.2.Final</version>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct</artifactId>
            <version>1.4.2.Final</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok-mapstruct-binding</artifactId>
            <version>0.2.0</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.20</version>
        </dependency>

        <dependency>
            <groupId>org.mariadb.jdbc</groupId>
            <artifactId>mariadb-java-client</artifactId>
            <version>2.7.3</version>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>5.5.7.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-jpamodelgen</artifactId>
            <version>5.5.7.Final</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.8.1</version>
        </dependency>

        <dependency>
            <groupId>org.springdoc</groupId>
            <artifactId>springdoc-openapi-maven-plugin</artifactId>
            <version>1.3</version>
        </dependency>

        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>31.0.1-jre</version>
        </dependency>
    </dependencies>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.keycloak.bom</groupId>
                <artifactId>keycloak-adapter-bom</artifactId>
                <version>${keycloak.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <build>
        <finalName>application</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <layers>
                        <enabled>true</enabled>
                    </layers>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springdoc</groupId>
                <artifactId>springdoc-openapi-maven-plugin</artifactId>
                <version>1.2</version>
                <configuration>
                    <apiDocsUrl>http://localhost:8080/v3/api-docs</apiDocsUrl>
                    <outputFileName>swagger.json</outputFileName>
                    <outputDir>srcrces</outputDir>
                    <skip>false</skip>
                </configuration>
                <executions>
                    <execution>
                        <id>integration-test</id>
                        <goals>
                            <goal>generate</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <configuration>
                    <source>11</source>
                    <target>11</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

Answer 1

库的导入和使用是正确的。版本里还有你要的方法，我刚查了

这表明编译器无法在类路径中找到相关的 jar。

你能运行 mvn install 如果它报告任何错误将它们添加到原始 post 并在这里添加评论以通知我。

编辑:

“找不到符号”错误主要出现在我们尝试使用程序中未定义或未声明的变量时。

当我们的代码编译时，编译器需要验证我们拥有的所有标识符。错误“找不到符号”意味着我们指的是编译器不知道的东西。

事实证明，在你的情况下，这是一个依赖版本冲突，可以像这样检测和解决 https://pretagteam.com/question/conflicting-library-version-in-a-java-maven-project

Maven Guava 缺少方法 Sets.symmetricDifference

Maven Guava missing method Sets.symmetricDifference

java

maven

guava