Invoking Maven for the goals: [org.apache.maven.plugins:maven-javadoc-plugin:2.7:javadoc] with no properties

M2_HOME=/usr/local/Cellar/maven/3.3.9/libexec
MAVEN_OPTS=  -Xmx512m
JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.7.0_65.jdk/Contents/Home/jre
JAVA_OPTS=null

[INFO] Scanning for projects...
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[INFO] Building ANTLR 4 Maven plugin 4.5.2
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] >>> maven-javadoc-plugin:2.7:javadoc (default-cli) > generate-sources @ antlr4-maven-plugin >>>
[INFO] 
[INFO] --- maven-enforcer-plugin:1.2:enforce (enforce-maven) @ antlr4-maven-plugin ---
[INFO] 
[INFO] --- maven-plugin-plugin:3.3:helpmojo (help-goal) @ antlr4-maven-plugin ---
[INFO] Using 'UTF-8' encoding to read mojo metadata.
[INFO] Applying mojo extractor for language: java-annotations
[INFO] Mojo extractor for language: java-annotations found 0 mojo descriptors.
[INFO] Applying mojo extractor for language: java
[INFO] Mojo extractor for language: java found 0 mojo descriptors.
[INFO] Applying mojo extractor for language: bsh
[INFO] Mojo extractor for language: bsh found 0 mojo descriptors.
[INFO] 
[INFO] <<< maven-javadoc-plugin:2.7:javadoc (default-cli) < generate-sources @ antlr4-maven-plugin <<<
[INFO] 
[INFO] --- maven-javadoc-plugin:2.7:javadoc (default-cli) @ antlr4-maven-plugin ---
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.009 s
[INFO] Finished at: 2016-01-29T15:30:46-08:00
[INFO] Final Memory: 18M/491M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-javadoc-plugin:2.7:javadoc (default-cli) on project antlr4-maven-plugin: An error has occurred in JavaDocs report generation:Unable to find javadoc command: The javadoc executable '/Library/Java/JavaVirtualMachines/jdk1.7.0_65.jdk/Contents/Home/jre/bin/javadoc' doesn't exist or is not a file. Verify the JAVA_HOME environment variable. -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
