Maven archetype - Velocity error because of a colon

问题:

I am having trouble creating a Maven archetype because of the presence of a colon character (':') in one of the resources. I have a Spring XML that includes that symbol:

<property name="maxSize" value="${ws.client.pool.maxSize:5}"/> 

When launching the archetype I get this error:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-archetype-plugin:2.2:generate  (default-cli) on project standalone-pom:  org.apache.maven.archetype.exception.ArchetypeGenerationFailure: Error merging velocity templates:  Encountered ":5}\"/>\n\t</bean>\n\t\n\t<bean id=\"fooServiceClient\" class=\"org.springframework.aop.framework.ProxyFactoryBean\">\n\t    <property name=\"targetSource\" ref=\"fooServiceClientPoolTargetSource\"/>\n\t</bean>\n\n</beans>\n"  at line 15, column 69 of archetype-resources/src/main/resources/spring/library.ws-client.xml [ERROR] Was expecting one of: [ERROR] "}" ... [ERROR] <DOT> ... [ERROR] "(" ... [ERROR] -> [Help 1] [ERROR]  

I tried configuring a escape character in the archetype's pom:

    <pluginManagement>         <plugins>             <plugin>                 <artifactId>maven-archetype-plugin</artifactId>                 <version>2.0</version>             </plugin>             <!-- Resources configuration -->             <plugin>                 <groupId>org.apache.maven.plugins</groupId>                 <artifactId>maven-resources-plugin</artifactId>                 <version>2.5</version>                 <configuration>                     <encoding>UTF-8</encoding>                     <escapeString>\</escapeString>                 </configuration>             </plugin>         </plugins>     </pluginManagement> 

However it still doesn't work. In this case:

<property name="maxSize" value="${ws.client.pool.maxSize\:5}"/> 

the error is as follows:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-archetype-plugin:2.2:generate  (default-cli) on project standalone-pom: org.apache.maven.archetype.exception.ArchetypeGenerationFailure:  Error merging velocity templates:  Encountered "\\" at line 15, column 69 of archetype-resources/src/main/resources/spring/library.ws-client.xml [ERROR] Was expecting one of: [ERROR] "}" ... [ERROR] <DOT> ... [ERROR] "(" ... [ERROR] -> [Help 1] [ERROR]  

Any idea on how to escape that colon?

回答1:

Had the same error with the following Spring injection code for an optional property:

@Value("${hostname:}") private String hostName; 

The solution:

#set( $dollar = '$' ) @Value("${dollar}{hostname:}") private String hostName; 

The crucial step is to wrap the reference to your $ constant in {curly braces}

回答2:

I worked out a solution based on a Velocity variable ($maxSize):

#set( $maxSize = '${ws.client.pool.maxSize:5}' )  <bean id="fooServiceClientPoolTargetSource" class="org.springframework.aop.target.CommonsPoolTargetSource">     <property name="targetBeanName" value="fooServiceClientTarget"/>     <property name="maxSize" value="$maxSize"/> 

文章来源: Maven archetype - Velocity error because of a colon