Question

我们在产品中使用GWT和mojo gwt-maven-plugin 2.4来编译GWT代码。但是我们观察到当我们运行mvn install时，即使没有对GWT代码进行代码更改，gwt maven插件也会运行排列。

在这个问题上挣扎了很长一段时间之后，我们可以通过简单的设置使用2个maven项目重现它：

第一个项目（MyGwtMavenSampleSource）：包含GWT代码以及gwt模块xml文件
第二个项目（MavenBuilderMod）：包含MyGwtMavenSampleSource作为maven依赖项并将构建战争文件。

以下是两个项目的poms：

第一个项目：MyGwtMavenSampleSource

<?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/maven-v4_0_0.xsd">
  <!-- POM file generated with GWT webAppCreator -->
  <modelVersion>4.0.0</modelVersion>
  <groupId>GWTMavenPlugin</groupId>
  <artifactId>MyGwtMavenSampleSource</artifactId>
  <packaging>jar</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>GWT Maven Archetype</name>

  <properties>
    <!-- Convenience property to set the GWT version -->
    <gwtVersion>2.4.0</gwtVersion>
    <!-- GWT needs at least java 1.5 -->
    <webappDirectory>${project.build.directory}/${project.build.finalName}</webappDirectory>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>
  <dependencies>
    <dependency>
      <groupId>com.google.gwt</groupId>
      <artifactId>gwt-servlet</artifactId>
      <version>${gwtVersion}</version>
      <scope>runtime</scope>
    </dependency>
    <dependency>
      <groupId>com.google.gwt</groupId>
      <artifactId>gwt-user</artifactId>
      <version>${gwtVersion}</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.7</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>javax.validation</groupId>
      <artifactId>validation-api</artifactId>
      <version>1.0.0.GA</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>javax.validation</groupId>
      <artifactId>validation-api</artifactId>
      <version>1.0.0.GA</version>
      <classifier>sources</classifier>
      <scope>test</scope>
    </dependency>
  </dependencies>
  <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.*</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.*</include>
                </includes>
            </resource>
        </resources>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

第二个项目：MavenBuilderMod

<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>GWTMavenPlugin</groupId>
  <artifactId>MavenBuilderMod</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <properties>
    <!-- Convenience property to set the GWT version -->
    <gwtVersion>2.4.0</gwtVersion>
    <!-- GWT needs at least java 1.5 -->
    <webappDirectory>${project.build.directory}/${project.build.finalName}</webappDirectory>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>
  <dependencies>
    <dependency>
      <groupId>com.google.gwt</groupId>
      <artifactId>gwt-servlet</artifactId>
      <version>${gwtVersion}</version>
      <scope>runtime</scope>
    </dependency>
    <dependency>
      <groupId>com.google.gwt</groupId>
      <artifactId>gwt-user</artifactId>
      <version>${gwtVersion}</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.7</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>javax.validation</groupId>
      <artifactId>validation-api</artifactId>
      <version>1.0.0.GA</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>javax.validation</groupId>
      <artifactId>validation-api</artifactId>
      <version>1.0.0.GA</version>
      <classifier>sources</classifier>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>GWTMavenPlugin</groupId>
      <artifactId>MyGwtMavenSampleSource</artifactId>
      <version>0.0.1-SNAPSHOT</version>
      <scope>compile</scope>
    </dependency>
  </dependencies>
  <build>
    <outputDirectory>${webappDirectory}/WEB-INF/classes</outputDirectory>
    <plugins>
         <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-dependency-plugin</artifactId>
            <version>2.8</version>
            <executions>
              <execution>
                <id>src-dependencies</id>
                <phase>package</phase>
                <goals>
                  <goal>unpack-dependencies</goal>
                </goals>
                <configuration>
                  <classifier>sources</classifier>
                  <failOnMissingClassifierArtifact>false</failOnMissingClassifierArtifact>
                  <outputDirectory>${project.build.directory}/sources</outputDirectory>
                </configuration>
              </execution>
            </executions>
        </plugin>
      <!-- GWT Maven Plugin -->
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>gwt-maven-plugin</artifactId>
        <version>2.4.0</version>
        <executions>
          <execution>
            <goals>
              <goal>compile</goal>
            </goals>
          </execution>
        </executions>
        <!-- Plugin configuration. There are many available options, see 
          gwt-maven-plugin documentation at codehaus.org -->
        <configuration>
          <runTarget>MyGwtMavenSampleSource.html</runTarget>
          <hostedWebapp>${webappDirectory}</hostedWebapp>
          <modules>
            <module>com.ca.gwt.maven.sample.MyGwtMavenSampleSource</module>
        </modules>
        </configuration>
      </plugin>

      <!-- Copy static web files before executing gwt:run -->
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-war-plugin</artifactId>
        <version>2.1.1</version>
        <executions>
          <execution>
            <phase>compile</phase>
          </execution>
        </executions>
        <configuration>
          <webappDirectory>${webappDirectory}</webappDirectory>
        </configuration>
      </plugin>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>2.3.2</version>
        <configuration>
          <source>1.5</source>
          <target>1.5</target>
        </configuration>
      </plugin>
    </plugins>
  </build>
</project>

所以，问题是，我们怎样才能使gwt-maven-plugin /编译器仅在代码更改时运行排列。

注意：如果gwt模块xml文件放在包含gwt-maven-plugin的同一maven模块中，这可以按预期工作（即仅在代码更改时运行排列）

Answer 1

根本问题是Maven对增量构建的破坏支持，以及可能在gwt-maven-plugin中破坏增量构建支持（特别是如果你仍然使用超过2年的版本！）。

gwt-maven-plugin以某种方式看到gwt.xml文件已经改变（跟踪你的第一个模块的构建，理想情况下，如果没有改变它应该真的是无操作;重新复制资源和/或重建JAR可能足以向下触发问题），特别是它比它生成的nocache.js文件更新。

我认为更好的设置是在第一个模块中运行gwt-maven-plugin并将所有内容打包到ZIP或WAR中，然后将其用作WAR覆盖。遗憾的是，运行DevMode有点困难，但是it's workable。

即使没有变化，gwt-maven-plugin也会运行排列

1 个答案: