Simply GWT 2.3 and Maven2(3) project in Eclipse Indigo

Question

When I try to create Maven project with this parameters: Archetype Group Id - org.codehaus.mojo; Archetype Artifact Id - gwt-maven-plugin; Archetype Version - 2.3.0-1. I get some strange errors:

• Plugin execution not covered by lifecycle configuration: org.codehaus.mojo:gwt-maven-plugin:2.3.0-1:generateAsync (execution: default, phase: generate-sources)

• Plugin execution not covered by lifecycle configuration: org.codehaus.mojo:gwt-maven-plugin:2.3.0-1:i18n (execution: default, phase: generate-sources)

• Plugin execution not covered by lifecycle configuration: org.apache.maven.plugins:maven-war-plugin:2.1.1:exploded (execution: default, phase: compile)

And some warnings as:

• Implementation of project facet jst.web could not be found. Functionality will be limited.

• Implementation of project facet wst.jsdt.web could not be found. Functionality will be limited.

This is my pom.xml:

<?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>net.test1</groupId>
  <artifactId>TestWebApp</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>GWT Maven Archetype</name>

  <properties>
    <!-- Convenience property to set the GWT version -->
    <gwtVersion>2.3.0</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>
    <!-- Generate compiled stuff in the folder used for developing mode -->
    <outputDirectory>${webappDirectory}/WEB-INF/classes</outputDirectory>

    <plugins>

      <!-- GWT Maven Plugin -->
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>gwt-maven-plugin</artifactId>
        <version>2.3.0-1</version>
        <executions>
          <execution>
            <goals>
              <goal>compile</goal>
              <goal>test</goal>
              <goal>i18n</goal>
              <goal>generateAsync</goal>
            </goals>
          </execution>
        </executions>
        <!-- Plugin configuration. There are many available options, see 
          gwt-maven-plugin documentation at codehaus.org -->
        <configuration>
          <runTarget>TestWebApp.html</runTarget>
          <hostedWebapp>${webappDirectory}</hostedWebapp>
          <i18nMessagesBundle>net.test1.TestWebApp.client.Messages</i18nMessagesBundle>
        </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>
            <goals>
              <goal>exploded</goal>
            </goals>
          </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>

And so on. What is this? I have tried all possible manuals on the Internet, and everywhere the same. I tried to create project manualy without eclipse and the same. I think, the problem is that manuals in the Internet was writing for old version of Eclipse, Maven, GWT. How can I beat it? How can I just create simple project with GWT 2.3, Maven2 plugin and Eclipse Indigo without errors end warnings?

Answer 1

This is known behavior, discussed on the eclipse wiki. See here: http://wiki.eclipse.org/M2E_plugin_execution_not_covered.

Don't just comment out the problematic sections of your pom, you really do need them. For instance The generated comment for that maven-war-plugin in the pom is "Copy static web files before executing gwt:run" This turns out to be true. If you comment out that plugin and "mvn clean gwt:run", static files will not be copied to the target folder and be unavailable to hosted mode.

Fortunately the workaround is easy. If you open up the pom in Eclipse, look in the Overview section, and click the error message at the top, it will give you some quick fix options. Such as "Permanently mark goal exploded in pom.xml as ignored." This will add some m2e configuration to your pom so it is no longer flagged as an error, and everything will work as before. The newly generated section in your pom is what is described in the link above as the "ignore" option.

Hope this helps.