AspectJ在Maven项目中,不工作/编织

Question

我正在尝试让AspectJ编织在一个简单的Maven项目中工作,并且不确定它出错的地方:当我使用"mvn exec:java"运行代码时,我看不到预期的输出.

我确信代码工作正常,因为我在STS中尝试了相同的工作,它工作正常.我只想让AspectJ在Maven项目中工作.

任何有关如何调试此类问题的提示将不胜感激.

<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.aop</groupId>
<artifactId>aop1</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>

<name>aop1</name>
<url>http://maven.apache.org</url>

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>

<dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>3.8.1</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjrt</artifactId>
        <version>1.7.3</version> <!-- specify your version -->
    </dependency>
</dependencies>

<build>
    <pluginManagement>
        <plugins>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>aspectj-maven-plugin</artifactId>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                        </goals>
                        <configuration>
                            <source>1.7</source>
                            <target>1.7</target>
                        </configuration>
                    </execution>
                </executions>
                <configuration>
                    <outxml>true</outxml>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>exec-maven-plugin</artifactId>
                <version>1.1</version>
                <configuration>
                    <mainClass>com.aop.aop1.App</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </pluginManagement>
</build>

Aspect文件与代码位于同一文件夹中:

    package com.aop.aop1;


public aspect aspect {

    pointcut secureAccess()
        : execution(* *.foo(..));

    before() : secureAccess() {
        System.out.println("BEHOLD the power of AOP !!!");
    }
}

Java文件:

package com.aop.aop1;
public class App 
{
    public static void main( String[] args )
    {
        System.out.println( "Hello World!" );
        foo();
    }
    public static void foo() {
        System.out.println(" IN FOO.");
    }
}

Answer 1

您的配置存在几个问题:

• 方面应Aspect使用大写"A" 命名,而不是aspect保留关键字.
• POM缺少结束</project>标记.
• POM有一个<pluginManagement>部分,但没有单独的<plugins>部分,即您为插件提供默认值,但实际上并未声明您要使用它们.因此,要么您没有使用独立<plugins>部分,<pluginManagement>要么在附加<plugins>部分重新声明插件.
• 的aspectj-maven-plugin需求<version>.你忘了指定一个.
• 该aspectj-maven-plugin还需要一个<complianceLevel>配置.
• 您使用编译时编织,因此您不需要<outxml>设置.它只需要加载时间编织.
• 该aspectjrt依赖于订单需要至少版本1.7.4要与所使用的版本不兼容AspectJ的Maven的插件,以编译源默认1.6.

除此之外,如果您没有任何令人信服的理由使用旧版本,我建议使用较新版本的Maven插件和依赖项,如JUnit和exec-maven-plugin.我还建议使用最新的AspectJ版本1.8.2,并指定在aspectj-maven-plugin内部使用它.

工作pom.xml中最小的变化:

<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.aop</groupId>
    <artifactId>aop1</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>aop1</name>
    <url>http://maven.apache.org</url>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</artifactId>
            <version>1.7.4</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>aspectj-maven-plugin</artifactId>
                <version>1.6</version>
                <configuration>
                    <complianceLevel>1.7</complianceLevel>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>compile</goal>
                        </goals>
                        <configuration>
                            <source>1.7</source>
                            <target>1.7</target>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>exec-maven-plugin</artifactId>
                <version>1.1</version>
                <configuration>
                    <mainClass>com.aop.aop1.App</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

工作的pom.xml与修改建议:

<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.aop</groupId>
    <artifactId>aop1</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <name>AOP Sample</name>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <aspectj.version>1.8.2</aspectj.version>
        <java.source-target.version>1.7</java.source-target.version>
    </properties>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>${java.source-target.version}</source>
                    <target>${java.source-target.version}</target>
                    <!-- IMPORTANT -->
                    <useIncrementalCompilation>false</useIncrementalCompilation>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>aspectj-maven-plugin</artifactId>
                <version>1.6</version>
                <configuration>
                    <showWeaveInfo>true</showWeaveInfo>
                    <source>${java.source-target.version}</source>
                    <target>${java.source-target.version}</target>
                    <Xlint>ignore</Xlint>
                    <complianceLevel>${java.source-target.version}</complianceLevel>
                    <encoding>UTF-8</encoding>
                    <verbose>true</verbose>
                </configuration>
                <executions>
                    <execution>
                        <!-- IMPORTANT -->
                        <phase>process-sources</phase>
                        <goals>
                            <goal>compile</goal>
                            <goal>test-compile</goal>
                        </goals>
                    </execution>
                </executions>
                <dependencies>
                    <dependency>
                        <groupId>org.aspectj</groupId>
                        <artifactId>aspectjtools</artifactId>
                        <version>${aspectj.version}</version>
                    </dependency>
                </dependencies>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>exec-maven-plugin</artifactId>
                <version>1.3</version>
                <configuration>
                    <mainClass>com.aop.aop1.App</mainClass>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.dstovall</groupId>
                <artifactId>onejar-maven-plugin</artifactId>
                <version>1.4.4</version>
                <executions>
                    <execution>
                        <configuration>
                            <onejarVersion>0.96</onejarVersion>
                            <mainClass>com.aop.aop1.App</mainClass>
                            <attachToBuild>true</attachToBuild>
                        </configuration>
                        <goals>
                            <goal>one-jar</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

    <pluginRepositories>
        <pluginRepository>
            <id>OneJAR googlecode.com</id>
            <url>http://onejar-maven-plugin.googlecode.com/svn/mavenrepo</url>
        </pluginRepository>
    </pluginRepositories>

    <dependencies>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjrt</artifactId>
            <version>${aspectj.version}</version>
            <!--<scope>runtime</scope>-->
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
</project>

顺便说一句,onejar-maven-plugin只是一个好东西,我喜欢用它来构建一个独立的超级JAR(又名胖JAR),其中包含运行软件所需的一切,即你的类/方面加上AspectJ运行时.你可以用它来运行程序

java -jar aop1-0.0.1-SNAPSHOT.one-jar.jar

输出应该类似于mvn exec:java没有Maven的东西:

Hello World!
BEHOLD the power of AOP !!!
IN FOO.