Maven Compiler Version from Command Line

Maven 2 default compiler version was 1.3, then for latest releases the default is 1.5. Maven 3 allows to set the compiler just in the parent pom.

Here is how to specify from command line the maven property that will set which compiler to use

$ mvn clean install -Dmaven.compiler.source=1.6 -Dmaven.compiler.target=1.6

This comes in handy especially to avoid errors like:

annotations are not supported in -source 1.3
(use -source 5 or higher to enable annotations)
    @Override public void initialize() {

Of course you can always edit the pom files as below but that would probably not be a good practice when you are not the owner of the project and the team maintaining it is using a different maven/compiler version than yours.

<plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-compiler-plugin</artifactId>
      <version>2.3.2</version>
      <configuration>
        <source>1.6</source> 
        <target>1.6</target>
      </configuration>
    </plugin>