how to make a executable jar pick the properties file during time time using maven

Question

Hi i am using maven buil to create an executable jar, i have few properties file. if i place the properties file in

src/main/resources 

maven packages them inside the jar itself. I dont want this to happen, instead i want to place the properties file in a folder called conf and i want these properties file to be avalable to the jar during runtime.

The reason why this is because in future the user can have the flexibility to chnage a few property values like port number etc without.

i have pasted the pom.xml below

<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>com.hp.nfv</groupId>
<artifactId>DescriptorA</artifactId>
<version>1.0.0</version>
  <name>DescriptorA/name>
  <dependencies>
   <dependency>
     <groupId>log4j</groupId>
     <artifactId>log4j</artifactId>
     <version>1.2.16</version>
    </dependency>
    <dependency>        
     <groupId>commons-cli</groupId>
     <artifactId>commons-cli</artifactId>
     <version>1.2</version>
   </dependency>
</dependencies>

<plugin>

    <groupId>org.apache.maven.plugins</groupId>

    <artifactId>maven-compiler-plugin</artifactId>

    <version>3.1</version>

    <configuration>

      <source>1.7</source>

      <target>1.7</target>

   </configuration>

 </plugin>

<plugin>
 <groupId>org.apache.maven.plugins</groupId>
 <artifactId>maven-dependency-plugin</artifactId>
 <executions>
<execution>
  <id>copy-dependencies</id>
  <phase>prepare-package</phase>
  <goals>
    <goal>copy-dependencies</goal>
  </goals>
  <configuration>
    <outputDirectory>${project.build.directory}/lib</outputDirectory>
    <overWriteReleases>false</overWriteReleases>
    <overWriteSnapshots>false</overWriteSnapshots>
    <overWriteIfNewer>true</overWriteIfNewer>
  </configuration>
</execution>
</executions>
</plugin>

<plugin>
 <groupId>org.apache.maven.plugins</groupId>
 <artifactId>maven-jar-plugin</artifactId>
 <version>2.3</version>
 <configuration>
  <excludes>
   <exclude>**/*.properties</exclude>
  </excludes>                    
 <archive>
  <manifest>
    <addClasspath>true</addClasspath>
    <classpathPrefix>lib/</classpathPrefix>
    <mainClass>com.abc.Descripto</mainClass>
  </manifest>
  <manifestEntries>
    <Class-Path>conf/</Class-Path>
  </manifestEntries>
 </archive>
 </configuration>
</plugin>

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-resources-plugin</artifactId>
  <version>2.3</version>
  <executions>
    <execution>
    <id>copy-resources</id>
    <phase>install</phase>
    <goals>
      <goal>copy-resources</goal>
     </goals>
    <configuration>
      <outputDirectory>${basedir}/target/conf</outputDirectory>
    <resources>
      <resource>
        <directory>src/main/resources</directory>
        <includes>
          <include>**/*.properties</include>
        </includes>
      </resource>
     </resources>
    </configuration>
   </execution>
  </executions>
 </plugin>

 </plugins>
</build>


</project>

the property file i am using is 'utility.properties' which is present in the src/main/resources

i am using this in the java code as below

ResourceBundle locationUtilityProp = ResourceBundle.getBundle("utility", locale);

but when i execute the above pom.xml file, i get a jar file , which on running gives the below error

java.util.MissingResourceException: Can't find bundle for base name utility

when I un jarred the jar file, i found no .properties files in it.

I am completely new to maven so please can anyone help me make this jar pick the properties file from a directory structure other than src/main/resources at run time.

Answer 1

I got this requirement working , and below i have answered in detail so that it can help someone else someday

package structure: you need to place .properties files inside src/main/resources when doing a maven build

src
 |-main/java/com.abc/.java classes
 |-main/resources/error.properties 

after maven generates a jar file, then create a folder called config and copy all .properties files inside it. and place your jar file in same directory as your config folder as below

example
 |-config
   -error.properties
 |-jar file generated by maven

code to fetch the resources files

static Locale locale = new Locale("en", "US");
 static ResourceBundle locationUtilityProp =ResourceBundle.getBundle("error", locale);

pom.xml to create an executable jar file

first tell maven not to include any of properties files present inside src/main/resources

<build>


<resources>
  <resource>
    <directory>src/main/resources</directory>
    <excludes>
      <exclude>**/*.properties</exclude>
    </excludes>  
  </resource>

</resources>      

now include maven compiler plugin

<plugins>
<plugin>

    <groupId>org.apache.maven.plugins</groupId>

    <artifactId>maven-compiler-plugin</artifactId>

    <version>3.1</version>

    <configuration>

      <source>1.7</source>

      <target>1.7</target>

   </configuration>
  </plugin>
 </plugins>
</build>

now include the maven assembly plugin to create an executable jar.

in the mention the folder name where you want maven to pick the resource files( in my case error.properties)

<plugin>
  <artifactId>maven-assembly-plugin</artifactId>
  <configuration>
    <archive>
      <manifest>
        <mainClass>com.abc.hello</mainClass>
      </manifest>
     <manifestEntries>
            <Class-Path>config/</Class-Path>
        </manifestEntries>
    </archive>
    <descriptorRefs>
      <descriptorRef>jar-with-dependencies</descriptorRef>
    </descriptorRefs>
  </configuration>
   <executions>
              <execution>
                <id>make-assembly</id>
                                    <!-- bind to the packaging phase -->
                <phase>package</phase> 
                <goals>
                    <goal>single</goal>
                </goals>
              </execution>
            </executions>
</plugin>