java - 在 AspectJ 示例项目中出现错误

Question

我是aspectJ的新手。我在 Aspect 类中遇到编译错误。运行项目时，出现编译错误。请帮我。放置下面得到的代码片段和错误：

项目结构：

MannersAspect.java

package main.java.testaop;

public aspect MannersAspect {
    pointcut callSayMessage() :
        call(public static void HelloWorld.say*(..));
    before() : callSayMessage() {
        System.out.println("Good day!");
    }
    after() : callSayMessage() {
        System.out.println("Thank you!");
    }
}

HelloWorld.java

package main.java.testaop;

public class HelloWorld {
    public static void say(String message) {
        System.out.println(message);
    }
    public static void sayToPerson(String message, String name) {
        System.out.println(name + ", " + message);
    }
}

pom.xml

<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>com.test</groupId>
    <artifactId>testaop</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>
    <name>testaop</name>

    <dependencies>                            
        <dependency>       
            <groupId>org.aspectj</groupId>    
            <artifactId>aspectjrt</artifactId>
            <version>1.8.4</version>          
        </dependency>                         
    </dependencies> 

    <build>
        <pluginManagement>
            <plugins>
                <!--This plugin's configuration is used to store Eclipse m2e settings only. It has no influence on the Maven build itself.-->
                <plugin>
                    <groupId>org.eclipse.m2e</groupId>
                    <artifactId>lifecycle-mapping</artifactId>
                    <version>1.0.0</version>
                    <configuration>
                        <lifecycleMappingMetadata>
                            <pluginExecutions>
                                <pluginExecution>
                                    <pluginExecutionFilter>
                                        <groupId>org.apache.maven.plugins</groupId>
                                        <artifactId>maven-compiler-plugin</artifactId>
                                        <versionRange>[2.5.1,)</versionRange>
                                        <goals><goal>compile</goal></goals>
                                    </pluginExecutionFilter>
                                    <action><ignore></ignore></action>
                                </pluginExecution>
                                <pluginExecution>
                                    <pluginExecutionFilter>
                                        <groupId>org.codehaus.mojo</groupId>
                                        <artifactId>aspectj-maven-plugin</artifactId>
                                        <versionRange>[1.7,)</versionRange>
                                        <goals><goal>compile</goal></goals>
                                    </pluginExecutionFilter>
                                    <action><ignore></ignore></action>
                                </pluginExecution>
                            </pluginExecutions>
                        </lifecycleMappingMetadata>
                    </configuration>
                </plugin>
            </plugins>
        </pluginManagement>

        <plugins>
            <plugin>                                                 
                <groupId>org.codehaus.mojo</groupId>            
                <artifactId>aspectj-maven-plugin</artifactId>        
                <executions>                                         
                    <execution>                                      
                        <goals><goal>compile</goal></goals>                                     
                        <configuration>                              
                            <source>1.5</source>                     
                            <target>1.5</target>                     
                        </configuration>                             
                    </execution>                                     
                </executions>                                        
            </plugin>
            <plugin>                                                 
                <groupId>org.codehaus.mojo</groupId>         
                <artifactId>exec-maven-plugin</artifactId>           
                <executions>                                         
                    <execution><goals><goal>java</goal></goals></execution>                                     
                </executions>                                        
                <configuration>                                      
                    <mainClass>main.java.testaop.HelloWorld</mainClass>            
                </configuration>                                     
            </plugin>
        </plugins>
    </build>
</project>

错误：

[ERROR] COMPILATION ERROR : 
[ERROR] D:\workspacedummy\testaop\src\main\java\testaop\MannersAspect.java:[3,7] error: class, interface, or enum expected
[ERROR] D:\workspacedummy\testaop\src\main\java\testaop\MannersAspect.java:[4,51] error: class, interface, or enum expected
[ERROR] D:\workspacedummy\testaop\src\main\java\testaop\MannersAspect.java:[4,72] error: malformed floating point literal
[ERROR] D:\workspacedummy\testaop\src\main\java\testaop\MannersAspect.java:[5,4] error: class, interface, or enum expected
[ERROR] D:\workspacedummy\testaop\src\main\java\testaop\MannersAspect.java:[7,4] error: class, interface, or enum expected
[ERROR] D:\workspacedummy\testaop\src\main\java\testaop\MannersAspect.java:[10,4] error: class, interface, or enum expected
[INFO] 6 errors 
[INFO] BUILD FAILURE
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.5.1:compile (default-compile) on project testaop: Compilation failure: Compilation failure:

Answer 1

您已经通过“New”->“Class”（因此是“.java”扩展名）在 Eclipse 中创建了方面，但您应该通过“New”->“Aspect”创建它（然后它将获得一个“.aj”延期）。

PS：您确实在 Eclipse 中安装了 AJDT（AspectJ 开发工具），不是吗？;-)

PPS：您的 Maven POM 也包含一些问题，例如对AspectJ Runtime 1.8.4的运行时依赖，但旧版本 1.5 中的AspectJ Maven 插件使用AspectJ Tools 1.7.3。当前插件版本 1.7 使用AspectJ Tools 1.8.2，如果需要，可以通过插件依赖配置升级到 1.8.4。