Class MadkitClassLoader

java.lang.Object
java.lang.ClassLoader
java.security.SecureClassLoader
java.net.URLClassLoader
madkit.kernel.MadkitClassLoader
All Implemented Interfaces:
Closeable, AutoCloseable
public final class MadkitClassLoader extends URLClassLoader
The MadkitClassLoader is the class loader used by MaDKit. It enables some specific features such as class hot reloading, jar loading, etc.
Since:
MaDKit 4.0

  • Method Details

    • getLoader

      public static MadkitClassLoader getLoader()
      Returns the last class loader, thus having all the loaded jars on the classpath.
      Returns:
      the last class loader.

    • loadClass

      public Class<?> loadClass(String name) throws ClassNotFoundException
      Overrides:
      loadClass in class ClassLoader
      Throws:
      ClassNotFoundException

    • reloadClass

      public static void reloadClass(String name) throws ClassNotFoundException
      Schedule the reloading of the byte code of a class for its next loading. So new instances, created using Class.newInstance() on a class object obtained with loadClass(String), will reflect compilation changes during run time. In fact, using loadClass(String) on the current MDK class loader obtained with getLoader() returns the class object corresponding to the last compilation of the java code available on the class path. Especially, this may return a different version than Class.forName(String) because Class.forName(String) uses the ClassLoader of the caller's current class which could be different than the current one (i.e. the one obtained getLoader()) if several reloads have been done. Especially, Agent.launchAgent(String, int) always uses the newest version of an agent class.
      Parameters:
      name - The fully qualified class name of the class
      Throws:
      ClassNotFoundException - if the class cannot be found on the class path

    • loadJarsFromDirectory

      public static boolean loadJarsFromDirectory(String directoryPath)
      Loads all jar files from a directory
      Parameters:
      directoryPath - directory's path
      Returns:
      true if at least one new jar has been loaded

    • getClassPackageName

      public static String getClassPackageName(String classFullName)
      Returns the package name for this class name. E.g. java.lang.Object as input gives java.lang as output.
      Parameters:
      classFullName - the full name of a class
      Returns:
      the package name or null if no package is defined

    • getClassSimpleName

      public static String getClassSimpleName(String classFullName)
      Returns the simple name for a full class name. E.g. java.lang.Object as input gives Object as output.
      Parameters:
      classFullName - the full name of a class
      Returns:
      the simple name of a class name

    • loadUrl

      public static boolean loadUrl(URL url)
      Adds a directory or a jar file to the class path.
      Parameters:
      url - the resource to add
      Returns:
      true if this url was not already loaded

    • getAllAgentClasses

      public static Set<String> getAllAgentClasses()
      Returns the names of all the available agent classes
      Returns:
      All the agent classes available on the class path

    • getMDKFiles

      public static Set<String> getMDKFiles()
      Returns the names of all the mdk properties files available
      Returns:
      All the mdk files available on the class path

    • getXMLConfigurations

      public static Set<String> getXMLConfigurations()
      Returns the names of all the xml configuration files available
      Returns:
      All the xml configuration file available on the class path

    • getAgentsWithMain

      public static Set<String> getAgentsWithMain()
      Returns:
      all the agent classes having a main method.

    • getAgentInstance

      public static <T extends Agent> T getAgentInstance(String agentClass)
      Returns an instance of a class from its name using the current class loader.
      Type Parameters:
      T - the type of the agent
      Parameters:
      agentClass - the name of the class
      Returns:
      an instance of the class or null if the class cannot be found.

    • findJavaExecutable

      public static String findJavaExecutable(String executable)
      Find a JDK/JRE program
      Parameters:
      executable - the name of the Java program to look for. E.g. "jarsigner", without file extension.
      Returns:
      the path to the executable or null if not found.

    • main

      public static void main(String[] args) throws IOException
      This is only used by ant scripts for building MDK jar files. This will create a file in java.io.tmpdir named agents.classes containing the agent classes which are on the class path and other information
      Parameters:
      args - the command line arguments
      Throws:
      FileNotFoundException - if the file is not found
      IOException - if the file cannot be written

    • toString

      public String toString()
      Overrides:
      toString in class Object