Interface ClasspathMonitorMBean

All Superinterfaces:
AbstractMonitorMBean, Runnable, Shutdownable
All Known Implementing Classes:
ClasspathMonitor
@Description("Classpath Monitor to be able to inspect the classpath and to find doublets") public interface ClasspathMonitorMBean extends AbstractMonitorMBean
All the methods which might help you to find classpath problems are collected in this JMX interface. Most of the methods returns a String because this can be easily shown in the JConsole.

Originally this interface was part of the PatternTesting project where part of this interface was moved to ResourcepathMonitorMBean with v1.6.4 to make this interface more clearly. And it is no longer Serializable because there is no need for it - all informations can be restored from the classpath.

Author:
oliver

  • Method Details

    • whichClass

      @Description("return the URI if the given class") URI whichClass(String name)
      Looks if the given classname can be found in the classpath.

      To avoid problems like "java.rmi.UnmarshalException: failed to unmarshal class java.lang.Object; nested exception is: java.io.IOException: unknown protocol: zip" no longer a URL but URI is now returned

      Parameters:
      name - of a class e.g. "java.lang.String"
      Returns:
      URI of the given resource (or null if resource was not found)

    • getNoClasses

      @Description("how often the given class is found in the classpath") int getNoClasses(String classname)
      Get the number of different versions of the given class.
      Parameters:
      classname - the name of the class
      Returns:
      how often the classname was found in the classpath

    • isDoublet

      @Description("is the given classname or resource found more than once in the classpath?") boolean isDoublet(Class<?> clazz)
      Is the given class a doublet, e.g. can it be found several times in the classpath? This method is the successor of the old isDoublet method which expects a String as argument.
      Parameters:
      clazz - the class
      Returns:
      true if more than one classname or resource was found in the classpath
      Throws:
      NoSuchElementException - if no classname or resource was found

    • getFirstDoublet

      @Description("returns the first doublet of the given classname or resource") URI getFirstDoublet(Class<?> clazz)
      Returns the first doublet of the given class. This method is the successor of the old isDoublet method which expects a String as argument.
      Parameters:
      clazz - the class
      Returns:
      the first doublet

    • getDoublets

      @Description("returns a sorted array of all found doublets") String[] getDoublets()
      Looks for each loaded class if it is a doublet or not.
      Returns:
      a sorted array with the found doublets

    • getDoubletClasspath

      @Description("returns the classpath where doublets were found") String[] getDoubletClasspath()
      Looks for each found doublet in which classpath it was found.
      Returns:
      the classpath where doublets were found

    • getDoublet

      @Description("returns the n'th doublet of the given classname or resource") URI getDoublet(Class<?> clazz, int n)
      Returns the n'th doublet of the given class. This method is the successor of the old isDoublet method which expects a String as argument.
      Parameters:
      clazz - the clazz
      n - number of wanted doublet
      Returns:
      the n'th doublet URL

    • getLoadedPackages

      @Description("returns an array of all loaded packages") String[] getLoadedPackages()
      Returns the packages which were loaded by the classloader. The loaded packages are returned as string array so that it can be displayed by the 'jconsole'.
      Returns:
      the packages as string array

    • getLoadedClasses

      @Description("returns an array of all loaded classes") String[] getLoadedClasses()
      Returns the classes which were loaded by the classloader. The loaded packages are returned as string array so that it can be displayed by the 'jconsole'.
      Returns:
      the classes as string array

    • isLoaded

      @Description("is the given classname already loaded?") boolean isLoaded(String classname)
      Is the given classname already loaded?.
      Parameters:
      classname - the name of the class
      Returns:
      true if given classname is already loaded

    • getUnusedClasses

      @Description("returns all classes which are not yet loaded") String[] getUnusedClasses()
      Returns the classes which are not yet loaded. These are the classes returned by getClasspathClasses() but not by getLoadedClasses().
      Returns:
      the classes which are not yet loaded

    • getUsedClasspath

      @Description("returns the classpath with the loaded classes") String[] getUsedClasspath()
      Gets the loaded classpath (without the bootclasspath) as URI array.
      Returns:
      the loaded classpath (sorted)

    • getUnusedClasspath

      @Description("returns the classpath which were not yet used") String[] getUnusedClasspath()
      The unused classpath is this path which are not used in past.
      Returns:
      the unused classpath (sorted)

    • getBootClasspath

      @Description("return ths boot classpath") String[] getBootClasspath()
      Gets the boot classpath.
      Returns:
      boot classpath

    • getClasspath

      @Description("returns the complete classpath which is seen by the application") String[] getClasspath()
      Gets the normal classpath which is also available by the system property "java.class.path".
      Returns:
      the classpath as String array

    • getClasspathClasses

      @Description("returns all classes of the classpath") String[] getClasspathClasses()
      Looks in the normal classpath after all classes and returns it as String array.
      Returns:
      all found classes in the classpath

    • getSerialVersionUID

      @Description("returns the servialSerialVersionUID of the given class") Long getSerialVersionUID(String classname) throws IllegalAccessException
      Gets the serial version uid.
      Parameters:
      classname - the name of the class
      Returns:
      the serialVersionUID of the given class (or null if the class does not have one)
      Throws:
      IllegalAccessException - e.g. if there is no SerialVersionUID

    • getManifestEntries

      @Description("return the manifest entries for the given class") String[] getManifestEntries(String classname)
      If a MANIFEST is found for a given class the attributes in this file should be returned as a string array. E.g. for commons-lang-2.3.jar the string array may looks like 
       Manifest-Version: 1.0
 Ant-Version: Apache Ant 1.6.5
 Created-By: 1.3.1_09-85 ("Apple Computer, Inc.")
 Package: org.apache.commons.lang
 Extension-Name: commons-lang
 Specification-Version: 2.3
 Specification-Vendor: Apache Software Foundation
 Specification-Title: Commons Lang
 Implementation-Version: 2.3
 Implementation-Vendor: Apache Software Foundation
 Implementation-Title: Commons Lang
 Implementation-Vendor-Id: org.apache
 X-Compile-Source-JDK: 1.3
 X-Compile-Target-JDK: 1.1
      Parameters:
      classname - the name of the class
      Returns:
      the attribute entries of the Manifest (or emtpy array if no Manifest or no attributes are found)

    • getIncompatibleClasses

      @Description("returns the doublet classes with different byte codes") String[] getIncompatibleClasses()
      Incompatible classes are doublets with different byte codes.
      Returns:
      doublet classes with different byte codes

    • getIncompatibleClasspath

      @Description("returns the classpath where incompatible classes were found") String[] getIncompatibleClasspath()
      Gets the incompatible classpath.
      Returns:
      the classpathes where incompatible classes were found

    • getClassloaderInfo

      @Description("returns some infos about the found classloader") String getClassloaderInfo()
      Returns some information about the classloader. At least the user should be informed if it is a unknown classloader which is not supported or not tested.
      Returns:
      e.g. "unknown classloader xxx - classpath can be wrong"