Class Loader


  • public class Loader
    extends Object
    The Loader class provides utility methods for the actual launchers to help launching the framework.
    • Constructor Summary

      Constructors 
      Constructor Description
      Loader​(File launchpadHome)
      Creates a loader instance to load from the given launchpad home folder.
    • Constructor Detail

      • Loader

        public Loader​(File launchpadHome)
        Creates a loader instance to load from the given launchpad home folder. Besides ensuring the existence of the launchpad home folder, the constructor also removes all but the most recent launcher JAR files from the Sling home folder (thus cleaning up from previous upgrades).
        Parameters:
        launchpadHome - The launchpad home folder. This must not be null or an empty string.
        Throws:
        IllegalArgumentException - If the launchpadHome argument is null or an empty string or if the launchpad home folder exists but is not a directory or if the Sling home folder cannot be created.
    • Method Detail

      • loadLauncher

        public Object loadLauncher​(String launcherClassName)
        Creates an URLClassLoader from a _launcher JAR_ file in the given launchpadHome directory and loads and returns the launcher class identified by the launcherClassName.
        Parameters:
        launcherClassName - The fully qualified name of a class implementing the Launcher interface. This class must have a public constructor taking no arguments.
        Returns:
        the Launcher instance loaded from the newly created classloader
        Throws:
        NullPointerException - if launcherClassName is null
        IllegalArgumentException - if the launcherClassName cannot be instantiated. The cause of the failure is contained as the cause of the exception.
      • cleanupVM

        public void cleanupVM()
        Tries to remove as many traces of class loaded by the framework from the Java VM as possible. Most notably the following traces are removed:
        • JavaBeans property caches
        • Close the Launcher Jar File (if opened by the platform)

        This method must be called when the notifier is called.

      • installLauncherJar

        public boolean installLauncherJar​(URL launcherJar)
                                   throws IOException
        Copies the contents of the launcher JAR as indicated by the URL to the sling home directory. If the existing file is is a more recent bundle version than the supplied launcher JAR file, it is is not replaced.
        Parameters:
        launcherJar - The URL to the launcher JAR
        Returns:
        true if the launcher JAR file has been installed or updated, false otherwise.
        Throws:
        IOException - If an error occurrs transferring the contents
      • spool

        public static void spool​(InputStream ins,
                                 File destFile)
                          throws IOException
        Spools the contents of the input stream to the given file replacing the contents of the file with the contents of the input stream. When this method returns, the input stream is guaranteed to be closed.
        Parameters:
        ins - The input stream to spool
        destFile - The file to spool the input stream contents to
        Throws:
        IOException - If an error occurrs reading or writing the input stream contents.
      • info

        protected void info​(String msg)
        Meant to be overridden to display or log info
        Parameters:
        msg - The message to display or log