JDK tools.jar as maven dependency

Question

I would like to put JDK tools.jar as compile dependency. I found some examples that indicate to use the systemPath property like the following:

<dependency>
  <groupId>com.sun</groupId>
  <artifactId>tools</artifactId>
  <scope>system</scope>
  <systemPath>${java.home}/../lib/tools.jar</systemPath>
</dependency>

The problem is that the path is not correct for Mac Os X (however it is correct for Windows and Linux). For it, the correct path is ${java.home}/../Classes/classes.jar .

I am looking for a way in order to define a maven property such that if system is detected as Mac Os X, value is set to ${java.home}/../Classes/classes.jar , otherwise it is set to ${java.home}/../lib/tools.jar (like it is possible to do with ANT). Does someone has an idea ?

Answer 1

That's what profiles are for, extract the path to a property, setup profiles for windows, OSX, etc, and define the property values appropriately.

Here's the doc page that discussing profiles for OSes: Maven Local Settings Model

It should endup looking something like this:

  <profiles>
    <profile>
      <id>windows_profile</id>
      <activation>
        <os>
          <family>Windows</family>
        </os>
      </activation>
      <properties>
        <toolsjar>${java.home}/../lib/tools.jar</toolsjar>
      </properties>
    </profile>
    <profile>
      <id>osx_profile</id>
      <activation>
        <os>
          <family>mac</family>
        </os>
      </activation>
      <properties>
        <toolsjar>${java.home}/../Classes/classes.jar</toolsjar>
      </properties>
    </profile>
  </profiles>

Answer 2

Thank you for introducing me maven profiles.

I have used profile as mentioned above and by activating a profile based on the presence of the desired file :

<profiles>
    <profile>
        <id>default-profile</id>
        <activation>
            <activeByDefault>true</activeByDefault>
            <file>
                <exists>${java.home}/../lib/tools.jar</exists>
            </file>
        </activation>
        <properties>
            <toolsjar>${java.home}/../lib/tools.jar</toolsjar>
        </properties>
    </profile>
    <profile>
        <id>mac-profile</id>
        <activation>
            <activeByDefault>false</activeByDefault>
            <file>
                <exists>${java.home}/../Classes/classes.jar</exists>
            </file>
        </activation>
        <properties>
            <toolsjar>${java.home}/../Classes/classes.jar</toolsjar>
        </properties>
    </profile>
</profiles>

I posted this answer to highlight a mistake in the previous post : the property section can only be used in activation section in order to activate a profile based on the existence of the specified property. In order to define a property, the properties section must be used like above.

Answer 3

Hi I know you guys are all smart, but it caused me couple of days to figure out the answer is not complete - both the profile and the dependency is necessary. I hope no one will waste time on this again. Please see my complete code below:

<profiles>
    <profile>
        <id>osx_profile</id>
        <activation>
            <activeByDefault>false</activeByDefault>
            <os>
                <family>mac</family>
            </os>
        </activation>
        <properties>
            <toolsjar>${java.home}/../Classes/classes.jar</toolsjar>
        </properties>
        <dependencies>
            <dependency>
                <groupId>com.sun</groupId>
                <artifactId>tools</artifactId>
                <version>1.6.0</version>
                <scope>system</scope>
                <systemPath>${toolsjar}</systemPath>
            </dependency>
        </dependencies>
    </profile>
</profiles>

Answer 4

Somehow, the eclipse in windows fails to pick up {java.home}. So, I had to set JAVA_HOME instead of java.home. JAVA_HOME was set in Run->Run Configurations->Environment. This worked for me with standard JDK(not Apple JDK).

<profiles>
        <profile>
            <id>windows-profile</id>
            <activation>
                <activeByDefault>true</activeByDefault>
                <file>
                    <exists>${JAVA_HOME}/lib/tools.jar</exists>
                </file>
            </activation>
            <properties>
                <toolsjar>${JAVA_HOME}/lib/tools.jar</toolsjar>
            </properties>
        </profile>
        <profile>
            <id>mac-profile</id>
            <activation>
                <activeByDefault>false</activeByDefault>
                <file>
                    <exists>${java.home}/../lib/tools.jar</exists>
                </file>
            </activation>
            <properties>
                <toolsjar>${java.home}/../lib/tools.jar</toolsjar>
            </properties>
        </profile>
    </profiles>


    <dependencies>
        <dependency>
                <groupId>jdk.tools</groupId>
                <artifactId>jdk.tools</artifactId>
                <version>jdk1.8.0</version>
                <scope>system</scope>
                <systemPath>${toolsjar}</systemPath>
            </dependency>
        </dependencies>

Answer 5

I found a solution in Q: Declare maven dependency on tools.jar to work on JDK 9

As the actual maven wizardry is quite elaborate, surprising to newcomers and a subject of future improvements, it is better not co copy-paste it around. Hence this module exists so you do not have to know or care about the details. ~~ https://github.com/olivergondza/maven-jdk-tools-wrapper

<dependency>
  <groupId>com.github.olivergondza</groupId>
  <artifactId>maven-jdk-tools-wrapper</artifactId>
  <version>0.1</version>
</dependency>

Answer 6

The comment of Edward is correct.

You need the profile AND you need the dependency outside of the profiles block. The profile just determines which value ${toolsjar} is gonna get.

<dependencies>
    <dependency>
        <groupId>jdk.tools</groupId>
        <artifactId>jdk.tools</artifactId>
        <version>jdk1.8.0</version>
        <scope>system</scope>
        <systemPath>${toolsjar}</systemPath>
    </dependency>
</dependencies>

Answer 7

Proper instructions for beginners

First Add this profile to Pom.xml file above tag or somewhere else in it.

<profiles>
    <profile>
        <id>default-profile</id>
        <activation>
            <activeByDefault>true</activeByDefault>
            <file>
                <exists>${java.home}/../lib/tools.jar</exists>
            </file>
        </activation>
        <properties>
            <toolsjar>${java.home}/../lib/tools.jar</toolsjar>
        </properties>
    </profile>
    <profile>
        <id>mac-profile</id>
        <activation>
            <activeByDefault>false</activeByDefault>
            <file>
                <exists>${java.home}/../Classes/classes.jar</exists>
            </file>
        </activation>
        <properties>
            <toolsjar>${java.home}/../Classes/classes.jar</toolsjar>
        </properties>
    </profile>
</profiles>

then Correct JRE path

Goto :

Windows > Preferecnes > Installed JREs

selected intalled JRE and double click on it or from right menu click edit and then make sure JRE Home path is inside JDK something like:

C:\\Program Files\\Java\\jdk1.8.0_181\\jre

if you have installed JRE seperatly then eclipse would have picked standalone JRE like:

C:\\Program Files\\Java\\jre1.8.0_181\\

so change it to JRE which come with JDK:

C:\\Program Files\\Java\\jdk1.8.0_181\\jre

Answer 8

my solution:

1. put the Sun's tools.jar to the $JAVA_HOME/lib
2. make a symlink in the $JAVA_HOME/.. named lib where target will be $JAVA_HOME/lib