无法从 Ant 构建运行 groovyc.xml

Question

我正试图从Ant build.xml文件内部运行groovyc。这是我的项目目录结构：

myapp/
    src/main/java
        <Some Java sources>
    src/main/groovy
        DemoController
    lib/main
        groovy-all-2.2.2.jar
        servlet-2.4.jar
    gen
        bin
        dist

这是我的compile目标：

<?xml version="1.0"?>
<project name="myapp" default="compile" basedir=".">
    <path id="groovy-path">
        <fileset dir="lib/main" includes="groovy-all-2.2.2.jar" />
    </path>
    <taskdef name="groovyc"
        classname="org.codehaus.groovy.ant.Groovyc"
        classpathref="groovy-path" />
    <!-- Other targets omitted for brevity... -->
    <target name="compile" depends="init">
        <echo message="Compiling Java sources..." />
        <javac destdir="gen/bin" includeantruntime="false">
            <src path="src/main/java" />
            <src path="lib/main" />
        </javac>
        <echo message="Compiling Groovy sources..." />
        <groovyc destdir="gen/bin">
            <src path="src/main/java" />
            <src path="src/main/groovy" />
            <src path="lib/main" />
        </groovyc>
    </target>
</project>

在我的代码中，在src/main/groovy下，我有一个名为DemoController:的Groovy类

package com.ar.myapp.controllers
import javax.servlet.http.HttpServlet
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
class DemoController extends HttpServlet {
    @Override
    void doGet(HttpServletRequest request, HttpServletResponse response) {
        String resp = "Hello, Groovy!";
        response.getWriter().write(resp);
    }
}

在Eclipse中（我安装了Groovy插件，并为所有这些代码创建了一个Groovy项目），我没有看到任何编译器错误或危险信号。但是当我运行Ant compile目标时，我会得到以下异常：

compile:
    [echo] Compiling Java sources...
    [javac] Compiling 1 source file to /home/myuser/sandbox/eclipse/workspace/myapp/gen/bin
    [echo] Compiling Groovy sources...
    [groovyc] Compiling 1 source file to /home/myuser/sandbox/eclipse/workspace/myapp/gen/bin
    [groovyc] org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed:
    [groovyc] /home/myuser/sandbox/eclipse/workspace/myapp/src/main/groovy/com/myapp/controllers/DemoController.groovy: 3: unable to resolve class javax.servlet.http.HttpServlet
    [groovyc]  @ line 3, column 1.
    [groovyc]    import javax.servlet.http.HttpServlet
    [groovyc]    ^
    [groovyc] 
    [groovyc] /home/myuser/sandbox/eclipse/workspace/myapp/src/main/groovy/com/myapp/controllers/DemoController.groovy: 4: unable to resolve class javax.servlet.http.HttpServletRequest
    [groovyc]  @ line 4, column 1.
    [groovyc]    import javax.servlet.http.HttpServletRequest;
    [groovyc]    ^
    [groovyc] 
    [groovyc] /home/myuser/sandbox/eclipse/workspace/myapp/src/main/groovy/com/myapp/controllers/DemoController.groovy: 5: unable to resolve class javax.servlet.http.HttpServletResponse
    [groovyc]  @ line 5, column 1.
    [groovyc]    import javax.servlet.http.HttpServletResponse;
    [groovyc]    ^
    [groovyc] 
    [groovyc] 3 errors

当我打开lib/main/servlet-2.4.jar时，我确实看到了Http*类打包在它们应该位于的位置（在javax.servlet.http下）。如果我没有将lib/main/servlet-2.4.jar添加到groovyc的路径中，我会理解这个错误，但这没有意义。这是怎么回事？

Answer 1

您需要将classpath属性添加到groovyc任务中。

  <groovyc destdir="gen/bin">
    <src path="src/main/groovy" />
    <classpath>
      <path location="gen/bin"/>
      <fileset dir="lib/main">
          <include name="*.jar" />
      </fileset>
    </classpath>
  </groovyc>

请注意，原始的build.xml在javac和groovyc任务中都包含Java源代码。您可以1）将javac目标（即gen/bin）添加到groovyc任务的类路径中，而不是引用源代码；或者2）在groovyc中一起编译java和groovy源代码，并完全删除javac步骤。

选项2：删除"javac"任务，并将groovy任务与java+groovy源代码结合使用：

  <groovyc destdir="gen/bin">
    <src path="src/main/java" />
    <src path="src/main/groovy" />
    <classpath>
      <fileset dir="lib/main">
          <include name="*.jar" />
      </fileset>
    </classpath>
  </groovyc>