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在Maven Build中，我使用字节代码生成库（Byte Buddy）动态生成一些Java类型。自然，这些类文件没有相应的源文件。这种方式只会产生几个班级。该项目的大部分代码将成为Java源代码。理想情况下，Java源代码将以静态方式引用生成的类型，而不是使用反射或运行时代码生成，这意味着类需要位于javac的编译类路径上。我是否可以在相同Maven项目的编译类路径上获得生成的类，即不需要单独的Maven项目和工件来保存包含源代码的Maven项目所引用的生成的字节码？我可以在同一个Maven项目中动态生成和引用源文件中的类吗？
更新：我已经试图把生成的类直接进入target/classes即project.build.outputDirectory，早在Maven构建生命周期，但似乎不是在类路径上。生成的类型无法通过 Maven编译器插件或 IDE解决。我也尝试使用Build Helper Maven Plugin在target下添加一个额外的资源目录，其中包含生成的类，然后将其自动复制到target/classes。这种配置表现出同样的问题。
更新：我已经创建了一个完整的公共回购在GitHub上：https://github.com/mches/so-42376851
这里是Maven的POM，因为我想有一个参考的字节码增强类静态类项目：
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>demo</groupId>
<artifactId>demo</artifactId>
<version>1.0-SNAPSHOT</version>
<relativePath>../pom.xml</relativePath>
</parent>
<artifactId>demo-enhanced</artifactId>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<phase>generate-resources</phase>
<goals>
<goal>unpack</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>demo</groupId>
<artifactId>demo-original</artifactId>
<version>${project.version}</version>
<overWrite>true</overWrite>
<outputDirectory>${project.build.outputDirectory}</outputDirectory>
<includes>**/*.class</includes>
<excludes>META-INF/</excludes>
</artifactItem>
</artifactItems>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>net.bytebuddy</groupId>
<artifactId>byte-buddy-maven-plugin</artifactId>
<executions>
<execution>
<phase>process-resources</phase>
<goals>
<goal>transform</goal>
</goals>
<configuration>
<initialization>
<entryPoint>net.bytebuddy.test.SimpleEntryPoint</entryPoint>
<groupId>demo</groupId>
<artifactId>demo-transformer</artifactId>
</initialization>
<transformations>
<transformation>
<plugin>net.bytebuddy.test.SimplePlugin</plugin>
<groupId>demo</groupId>
<artifactId>demo-transformer</artifactId>
</transformation>
</transformations>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
这里是父POM：
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>demo</groupId>
<artifactId>demo</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>pom</packaging>
<modules>
<module>demo-original</module>
<module>demo-transformer</module>
<module>demo-enhanced</module>
</modules>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
<byte-buddy.version>1.6.9</byte-buddy.version>
</properties>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>net.bytebuddy</groupId>
<artifactId>byte-buddy</artifactId>
<version>${byte-buddy.version}</version>
</dependency>
<dependency>
<groupId>demo</groupId>
<artifactId>demo-original</artifactId>
<version>${project.version}</version>
</dependency>
<dependency>
<groupId>demo</groupId>
<artifactId>demo-transformer</artifactId>
<version>${project.version}</version>
</dependency>
<dependency>
<groupId>demo</groupId>
<artifactId>demo-enhanced</artifactId>
<version>${project.version}</version>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>net.bytebuddy</groupId>
<artifactId>byte-buddy-maven-plugin</artifactId>
<version>${byte-buddy.version}</version>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
富/ Bar.java（原始源） ：
package foo;
public class Bar {
}
净/ bytebuddy /测试/ SimplePlugin.java（字节代码增强剂）：
package net.bytebuddy.test;
import net.bytebuddy.build.Plugin;
import net.bytebuddy.description.modifier.Visibility;
import net.bytebuddy.description.type.TypeDescription;
import net.bytebuddy.dynamic.DynamicType;
import net.bytebuddy.implementation.FieldAccessor;
public class SimplePlugin implements Plugin {
@Override
public boolean matches(TypeDescription target) {
return target.getName().equals("foo.Bar");
}
@Override
public DynamicType.Builder<?> apply(DynamicType.Builder<?> builder, TypeDescription typeDescription) {
if (typeDescription.getTypeName().equals("foo.Bar")) {
builder = builder.defineField("qux", String.class, Visibility.PRIVATE)
.defineMethod("getQux", String.class, Visibility.PUBLIC)
.intercept(FieldAccessor.ofField("qux"))
.defineMethod("setQux", void.class, Visibility.PUBLIC)
.withParameter(String.class)
.intercept(FieldAccessor.ofField("qux"));
}
return builder;
}
}
富/ Baz.java（静态源文件引用动态型）：
package foo;
public class Baz {
private Bar bar = new Bar();
public String getQuux() {
return bar.getQux();
}
public void setQuux(String quux) {
bar.setQux(quux);
}
}
更新： Maven似乎理解一个结构涉及整合模块与增强字节码和静态类源代码，一个以及每个模块的独立模块，但IDE，IntelliJ和Eclipse无法理解Maven的结构类路径。
也许你可以看看jax-b的源代码：xjc它不会simil关于生成源代码阶段的东西 – HRgiger