Package org.eclipse.mat.parser.internal

Class SnapshotImpl

java.lang.Object
org.eclipse.mat.parser.internal.SnapshotImpl
All Implemented Interfaces:
ISnapshot
public final class SnapshotImpl extends Object implements ISnapshot
The implementation of the ISnapshot representing the entire heap dump.

  • Method Details

    • readFromFile

      public static SnapshotImpl readFromFile(File file, String prefix, IProgressListener listener) throws SnapshotException, IOException
      Read the snapshot from an already indexed dump.
      Parameters:
      file - the dump file
      prefix - the prefix of the path to find the index files
      listener - to report progress
      Returns:
      the ISnapshot
      Throws:
      SnapshotException - problem reading index files
      IOException - file I/O problem

    • create

      public static SnapshotImpl create(XSnapshotInfo snapshotInfo, String objectReaderUniqueIdentifier, IObjectReader heapObjectReader, HashMapIntObject<ClassImpl> classCache, HashMapIntObject<XGCRootInfo[]> roots, HashMapIntObject<HashMapIntObject<XGCRootInfo[]>> rootsPerThread, BitField arrayObjects, IndexManager indexManager, IProgressListener listener) throws IOException, SnapshotException
      Create the snapshot after a fresh parse.
      Parameters:
      snapshotInfo - the basic data about the snapshot
      objectReaderUniqueIdentifier - the type of the snapshot from the parser
      heapObjectReader - how to read objects from the file
      classCache - all the classes
      roots - all the GC roots
      rootsPerThread - the GC roots per thread
      arrayObjects - which objects are arrays
      indexManager - all the indexes
      listener - to report progress
      Returns:
      the new ISnapshot
      Throws:
      IOException - a file I/O problem
      SnapshotException - another problem

    • getSnapshotInfo

      public XSnapshotInfo getSnapshotInfo()
      Description copied from interface: ISnapshot
      Get info object describing the snapshot.

      Performance: Fast - in memory.

      Specified by:
      getSnapshotInfo in interface ISnapshot
      Returns:
      info object describing the snapshot

    • getGCRoots

      public int[] getGCRoots() throws SnapshotException
      Description copied from interface: ISnapshot
      Get all GC roots.

      A GC root is an object which doesn't need to be referenced to remain in the heap, e.g. all objects created in the thread stack frame.

      Performance: Fast - in memory.

      Specified by:
      getGCRoots in interface ISnapshot
      Returns:
      int[] containing the objectIds of all GC roots
      Throws:
      SnapshotException - should not normally occur

    • getClasses

      public Collection<IClass> getClasses() throws SnapshotException
      Description copied from interface: ISnapshot
      Get all classes.

      The returned class is a snapshot representation of a Java class. It offers means to get to its name, class loader, fields, inheritance relationships and most importantly to all of its objects found in the heap.

      Performance: Fast - in memory.

      Specified by:
      getClasses in interface ISnapshot
      Returns:
      collection of all classes
      Throws:
      SnapshotException - should not normally occur

    • getClassesByName

      public Collection<IClass> getClassesByName(String name, boolean includeSubClasses) throws SnapshotException
      Description copied from interface: ISnapshot
      Get all classes by name.

      This method returns you for one full class name all classes with this name. Usually you will get only one class back, but in the case of multiple class loaders which have loaded a class with the same name twice (or even the same class) you will get multiple snapshot class representations back as only the combination of class and class loader is unique, not the name alone.

      Performance: Fast - in memory.

      Specified by:
      getClassesByName in interface ISnapshot
      Parameters:
      name - name for the class
      includeSubClasses - flag indicating whether or not to include also classes derived from matching classes (the name isn't taken into account for sub classes anymore)
      Returns:
      collection of matching classes - current implementations can return null if there is no class found
      Throws:
      SnapshotException - should not normally occur

    • getClassesByName

      public Collection<IClass> getClassesByName(Pattern namePattern, boolean includeSubClasses) throws SnapshotException
      Description copied from interface: ISnapshot
      Get all classes by name pattern.

      This method returns you all classes with a name matching the regular expression pattern.

      Performance: Fast - in memory, but needs iteration over all classes.

      Specified by:
      getClassesByName in interface ISnapshot
      Parameters:
      namePattern - name pattern for the class (regular expression)
      includeSubClasses - flag indicating whether or not to include also classes derived from matching classes (the name isn't taken into account for subclasses anymore)
      Returns:
      collection of matching classes
      Throws:
      SnapshotException - should not normally occur

    • getHistogram

      public Histogram getHistogram(IProgressListener listener) throws SnapshotException
      Description copied from interface: ISnapshot
      Get histogram for the whole snapshot.

      This histogram lists all classes and class loaders and how many objects of the classes exist in the snapshot along with the memory consumption.

      Performance: Fast - in memory.

      Specified by:
      getHistogram in interface ISnapshot
      Parameters:
      listener - progress listener informing about the current state of execution
      Returns:
      histogram
      Throws:
      SnapshotException - if there is a problem retrieving the information such as because of a damaged index.

    • getHistogram

      public Histogram getHistogram(int[] objectIds, IProgressListener progressMonitor) throws SnapshotException
      Description copied from interface: ISnapshot
      Get histogram for some specific objects - usually the result of other calls to the snapshot.

      This histogram lists all classes and class loaders and how many objects of the classes exist among the given objects along with the memory consumption.

      Performance: Fast to medium - on index (object id -> class id); depending on the number of objects.

      Specified by:
      getHistogram in interface ISnapshot
      Parameters:
      objectIds - object ids for which the histogram should be computed
      progressMonitor - progress listener informing about the current state of execution
      Returns:
      histogram - current implementations can return null if the listener is cancelled
      Throws:
      SnapshotException - if there is a problem retrieving the information such as because of a damaged index.

    • getInboundRefererIds

      public int[] getInboundRefererIds(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get all objects referencing the given object.

      This is the inverse of ISnapshot.getOutboundReferentIds(int).

      Performance: Relatively fast - single index operation.

      Specified by:
      getInboundRefererIds in interface ISnapshot
      Parameters:
      objectId - object which is referenced
      Returns:
      objects referencing the given object
      Throws:
      SnapshotException - should not normally occur

    • getOutboundReferentIds

      public int[] getOutboundReferentIds(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get all objects referenced by the given object.

      This shows the keep-alive relationship between objects and includes:

      • a reference from an object to its type (class)
      • reference fields in objects
      • references in object arrays
      • a references from a class to its class loader
      • a reference from a class to its superclass
      • static reference fields in class objects
      • classes loaded by a class loader

      This is the inverse of ISnapshot.getInboundRefererIds(int).

      Performance: Relatively fast - single index operation.

      Specified by:
      getOutboundReferentIds in interface ISnapshot
      Parameters:
      objectId - object which is referencing
      Returns:
      objects referenced by the given object
      Throws:
      SnapshotException - should not normally occur

    • getInboundRefererIds

      public int[] getInboundRefererIds(int[] objectIds, IProgressListener progressMonitor) throws SnapshotException
      Description copied from interface: ISnapshot
      Get all objects referencing the given objects.

      Hint: This method is handy if you want to learn which classes reference a class. Therefore you would call this method with all objects of your class of interest and get a histogram out of the result.

      This is the inverse of ISnapshot.getOutboundReferentIds(int[], IProgressListener).

      Performance: Fast to slow - on index; depending on the number of objects and the references.

      Specified by:
      getInboundRefererIds in interface ISnapshot
      Parameters:
      objectIds - objects which are referenced
      progressMonitor - progress listener informing about the current state of execution
      Returns:
      objects referencing the given objects - current implementations can return null if the operation is cancelled
      Throws:
      SnapshotException - should not normally occur

    • getOutboundReferentIds

      public int[] getOutboundReferentIds(int[] objectIds, IProgressListener progressMonitor) throws SnapshotException
      Description copied from interface: ISnapshot
      Get all objects referenced by the given objects.

      Hint: This method is handy if you want to learn which classes are referenced by a class. Therefore you would call this method with all objects of your class of interest and get a histogram out of the result. This is the inverse of ISnapshot.getInboundRefererIds(int[], IProgressListener).

      Performance: Fast to slow - on index; depending on the number of objects and the references.

      Specified by:
      getOutboundReferentIds in interface ISnapshot
      Parameters:
      objectIds - objects which are referencing
      progressMonitor - progress listener informing about the current state of execution
      Returns:
      objects referenced by the given objects - current implementations can return null if the operation is cancelled
      Throws:
      SnapshotException - should not normally occur

    • getPathsFromGCRoots

      public IPathsFromGCRootsComputer getPathsFromGCRoots(int objectId, Map<IClass,Set<String>> excludeList) throws SnapshotException
      Description copied from interface: ISnapshot
      Get interactive computer for paths from GC roots to the given object.

      Hint: This method is handy if you want to learn which objects are responsible for the given object to remain in memory. Since the snapshot implementation artificially creates references from the object to its class and from the class to its class loader you can even see why a class or class loaders remains in memory, i.e. which other objects hold references to objects of the class or class loader of interest.

      Performance: Fast to slow - on index; depending on the number and length of GC root paths.

      Specified by:
      getPathsFromGCRoots in interface ISnapshot
      Parameters:
      objectId - object for which the GC root paths should be determined
      excludeList - a map specifying paths through which objects have to be avoided and not reported. Each entry in the map has the IClass as a key, and a Set<String> set, specifying which fields exactly from this key class have to be avoided. If for a key IClass the value (Set<String>) null is specified, then paths through any of the fields will be avoided
      Returns:
      interactive computer for paths from GC roots to the given object
      Throws:
      SnapshotException - if a problem occurs creating the paths computer

    • getMultiplePathsFromGCRoots

      public IMultiplePathsFromGCRootsComputer getMultiplePathsFromGCRoots(int[] objectIds, Map<IClass,Set<String>> excludeList) throws SnapshotException
      Description copied from interface: ISnapshot
      Returns an IMultiplePathsFromGCRootsComputer object, which can be used to calculate the shortest path from the GC roots to each of objects in the specified object set.
      Specified by:
      getMultiplePathsFromGCRoots in interface ISnapshot
      Parameters:
      objectIds - the IDs of the objects for which a shortest path has to be calculated
      excludeList - a map specifying paths through which objects have to be avoided and not reported. Each entry in the map has the IClass as a key, and a Set<String> set, specifying which fields exactly from this key class have to be avoided. If for a key IClass the value (Set<String>) null is specified, then paths through any of the fields will be avoided
      Returns:
      IMultiplePathsFromGCRootsComputer The object which can be used to carry out the actual computation and
      Throws:
      SnapshotException - if a problem occurs creating the paths computer

    • getRetainedSet

      public int[] getRetainedSet(int[] objectIds, IProgressListener progressMonitor) throws SnapshotException
      Description copied from interface: ISnapshot
      Get retained set of objects for the given objects (including the given objects).

      The retained set includes the given objects and all objects which are lifetime-dependent on them, i.e. which would be garbage collected if the references to the given objects would be lost and the objects garbage collected.

      Performance: Usually extremely slow - on index; depending on the number of objects and the references (deep).

      Specified by:
      getRetainedSet in interface ISnapshot
      Parameters:
      objectIds - objects on which the retained set should be determined
      progressMonitor - progress listener informing about the current state of execution
      Returns:
      retained set of objects for the given objects
      Throws:
      SnapshotException - if a problem occurs, for example if the operation was interrupted

    • getRetainedSet

      public int[] getRetainedSet(int[] objectIds, String[] fieldNames, IProgressListener listener) throws SnapshotException
      Description copied from interface: ISnapshot
      Get retained set of objects for the given fields at the given objects (excluding the given objects).

      The retained set includes the objects referenced by the fields on the given objects and all objects which are lifetime-dependent on them, i.e. which would be garbage collected if the references at the given fields at the given objects would be nulled.

      Performance: Usually extremely slow - on index; depending on the number of objects and the references (deep).

      Specified by:
      getRetainedSet in interface ISnapshot
      Parameters:
      objectIds - objects on which the retained set should be determined
      fieldNames - the names of the fields which could retain the objects
      listener - progress listener informing about the current state of execution
      Returns:
      retained set of objects for the given objects
      Throws:
      SnapshotException - if there was a problem, such as on cancellation

    • getRetainedSet

      public int[] getRetainedSet(int[] objectIds, ExcludedReferencesDescriptor[] excludedReferences, IProgressListener progressMonitor) throws SnapshotException
      Description copied from interface: ISnapshot
      Get retained set of objects for the given fields at the given objects (excluding the given objects).

      The retained set includes the objects referenced by the fields on the given objects and all objects which are lifetime-dependent on them, i.e. which would be garbage collected if the references at the given fields at the given objects would be nulled.

      Performance: Usually extremely slow - on index; depending on the number of objects and the references (deep).

      Specified by:
      getRetainedSet in interface ISnapshot
      Parameters:
      objectIds - objects on which the retained set should be determined
      excludedReferences - references which should not be followed
      progressMonitor - progress listener informing about the current state of execution
      Returns:
      retained set of objects for the given objects
      Throws:
      SnapshotException - if there was a problem, such as on cancellation

    • getMinRetainedSize

      public long getMinRetainedSize(int[] objectIds, IProgressListener progressMonitor) throws UnsupportedOperationException, SnapshotException
      Description copied from interface: ISnapshot
      Calculate the minimum retained size for the given objects. Works much faster than getting the min. retained set by getMinRetainedSet() and calculating the size of the min. retained set.
      Specified by:
      getMinRetainedSize in interface ISnapshot
      Parameters:
      objectIds - objects on which the minimum retained set should be determined
      progressMonitor - progress listener informing about the current state of execution
      Returns:
      the minimum retained set of objects for the given objects
      Throws:
      SnapshotException - if there was a problem, such as on cancellation
      UnsupportedOperationException

    • getMinRetainedSet

      public int[] getMinRetainedSet(int[] objectIds, IProgressListener progressMonitor) throws UnsupportedOperationException, SnapshotException
      Description copied from interface: ISnapshot
      Calculate the minimum retained set of objects for the given objects (including the given objects).

      The minimum retained set includes the given objects and the union of the retained sets for each of the given objects (see getRetainedSet() for an explanation of a retained set). The union of the retained sets of the single objects is potentially smaller than the retained set of all of them, because some objects which are shared between two of the given objects may not appear in the retained set of any of the single objects, but will appear in the retained set if we take them as a whole. Because of it's faster performance the method is suitable to "mine" for a potentially big retained set (e.g. execute this method for all class loaders and see for potentially big ones). One can use the getRetainedSet() method afterwards to get the correct retained set.

      Performance: Usually fast - for smaller sets this method is much faster than getRetainedSet

      Specified by:
      getMinRetainedSet in interface ISnapshot
      Parameters:
      objectIds - objects on which the minimum retained set should be determined
      progressMonitor - progress listener informing about the current state of execution
      Returns:
      the minimum retained set of objects for the given objects
      Throws:
      SnapshotException - if there was a problem, such as on cancellation
      UnsupportedOperationException

    • getTopAncestorsInDominatorTree

      public int[] getTopAncestorsInDominatorTree(int[] objectIds, IProgressListener listener) throws SnapshotException
      Description copied from interface: ISnapshot
      Get the top-ancestors in the dominator tree from the supplied objectIds. The result will be a list of objects (int[]), such that no object from the return list is parent of another object in the returned list. I.e. from a list of objects this method will return only the ones which are independent on one another. It is then correct to sum the retained sizes of the returned objects.
      Specified by:
      getTopAncestorsInDominatorTree in interface ISnapshot
      Parameters:
      objectIds - the objects for which the top-ancestors in the Dominator tree have to be found
      listener - progress listener informing about the current state of execution
      Returns:
      int[] the objects which not in a parent/child relation in the dominator tree
      Throws:
      SnapshotException - if the dominator tree has not been calculated

    • calculateDominatorTree

      public void calculateDominatorTree(IProgressListener listener) throws SnapshotException, IProgressListener.OperationCanceledException
      Calculates the dominator tree after a parse
      Parameters:
      listener - to report progress
      Throws:
      SnapshotException - if a problem occurred
      IProgressListener.OperationCanceledException - if the calculation was cancelled by user via the listener

    • getImmediateDominatedIds

      public int[] getImmediateDominatedIds(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get objects the given object directly dominates, i.e. the objects which are life-time dependent on the given object (not recursively, so just the directly dependent objects), i.e. the objects which would get collected as garbage if the given object would be gone from the heap.
      Specified by:
      getImmediateDominatedIds in interface ISnapshot
      Parameters:
      objectId - object for which the directly dominated objects should be returned
      Returns:
      objects the given object directly dominates
      Throws:
      SnapshotException - if the dominator tree has not been calculated

    • getImmediateDominatorId

      public int getImmediateDominatorId(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get object which directly dominates the given object, i.e. the object which controls the life-time of the given object (not recursively, so just the directly controlling object), i.e. the object which would cause the given object to be collected as garbage if it would be gone from the heap.
      Specified by:
      getImmediateDominatorId in interface ISnapshot
      Parameters:
      objectId - object for which the directly dominated objects should be returned
      Returns:
      Object id of the dominator. -1 if the object is dominated by the root of the dominator tree.
      Throws:
      SnapshotException - if the dominator tree has not been calculated

    • getDominatorsOf

      public DominatorsSummary getDominatorsOf(int[] objectIds, Pattern excludePattern, IProgressListener progressListener) throws SnapshotException
      Description copied from interface: ISnapshot
      Get a summary of the dominators for all the given objects. The summary can be viewed on grouped by classes or class loaders

      If an exclude pattern is provided, instead of returning the immediate dominator right away, its class name will be checked against the exclude pattern. If it matches the pattern, the dominator of this dominator will be taken and checked, and so on ... until a dominator not matching the pattern is found or the dominator tree root is reached.

      Specified by:
      getDominatorsOf in interface ISnapshot
      Parameters:
      objectIds - the objects for which we want the dominator summary (e.g. all objects of a given class)
      excludePattern - An exclude pattern. Domminators whose class name matches the pattern will be omitted and their dominator will be taken
      progressListener - progress listener informing about the current state of execution
      Returns:
      DominatorsSummary the returned DominatorSummary contains the summary of the dominators grouped by classes or class loaders
      Throws:
      SnapshotException - if the dominator tree has not been calculated

    • getObject

      public IObject getObject(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get object abstracting the real Java Object from the heap dump identified by the given id.

      Performance: Relatively fast - single index operation.

      Specified by:
      getObject in interface ISnapshot
      Parameters:
      objectId - id of object you want a convenient object abstraction for
      Returns:
      object abstracting the real Java Object from the heap dump identified by the given id
      Throws:
      SnapshotException - if there is a problem, such as perhaps an invalid objectId

    • getGCRootInfo

      public GCRootInfo[] getGCRootInfo(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get the GC root info for an object. If the provided object is not a GC root, then null will be returned; otherwise, a GCRootInfo[]. An object can be a GC root for more than one reason and the returned array will contain one instance of GCRootInfo for each of the reasons (e.g. one GCRootInfo for every thread where an object is a java local variable)

      Performance: Fast - in memory.

      Specified by:
      getGCRootInfo in interface ISnapshot
      Parameters:
      objectId - id of object you want the GC root info for
      Returns:
      null if this object is no GC root or GCRootInfo[] if it is
      Throws:
      SnapshotException - on an unexpected problem

    • getClassOf

      public IClass getClassOf(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get object abstracting the real Java Class this object was an instance of in the heap dump identified by the given id.

      Performance: Relatively fast - single index operation.

      Specified by:
      getClassOf in interface ISnapshot
      Parameters:
      objectId - id of object you want the convenient class abstraction for
      Returns:
      object abstracting the real Java Class this object was an instance of in the heap dump identified by the given id
      Throws:
      SnapshotException - if there is an unexpected problem

    • mapIdToAddress

      public long mapIdToAddress(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Map object id (snapshot internal identity assigned during parsing) to object address (memory address where the object was stored).

      Performance: Fast - in memory.

      Specified by:
      mapIdToAddress in interface ISnapshot
      Parameters:
      objectId - id of object you want the address for
      Returns:
      object address address of object with that id
      Throws:
      SnapshotException - shouldn't normally happen as often a RuntimeException would be thrown if the object ID is invalid.

    • getHeapSize

      public long getHeapSize(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get heap size for just the given object. new long[Integer.MAX_VALUE] is bigger than Integer.MAX_VALUE bytes, so this method now returns a long

      Performance: Usually fast - in memory for non-array objects and single index operation for array objects.

      Specified by:
      getHeapSize in interface ISnapshot
      Parameters:
      objectId - id of object for which you want the heap size for
      Returns:
      heap size for the given object.
      Throws:
      SnapshotException - on an unexpected problem

    • getHeapSize

      public long getHeapSize(int[] objectIds) throws UnsupportedOperationException, SnapshotException
      Description copied from interface: ISnapshot
      Get the total shallow heap size for a set of objects.

      Performance: Relatively fast - using this method to calculate the total size of a set of objects is much faster than iterating over the ids and calling getHeapSize for each single object

      Specified by:
      getHeapSize in interface ISnapshot
      Parameters:
      objectIds - ids of the objects for which you want the heap size for
      Returns:
      total heap size for the given object set
      Throws:
      SnapshotException - on an unexpected problem
      UnsupportedOperationException

    • calculateMinRetainedHeapSizeForClasses

      public void calculateMinRetainedHeapSizeForClasses(IProgressListener listener) throws SnapshotException
      Calculate for each class an approximation for the retained size of all instances of that class.
      Parameters:
      listener - for reporting progress
      Throws:
      SnapshotException - if there is a problem

    • getRetainedHeapSize

      public long getRetainedHeapSize(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get retained heap size for the given object.

      The retained heap size is the memory which would be freed if all references to the given object would be released. It is extracted from the dominator tree and isn't available if the dominator tree isn't available itself.

      Performance: Relatively fast - single index operation.

      Specified by:
      getRetainedHeapSize in interface ISnapshot
      Parameters:
      objectId - id of object for which you want the retained heap size for
      Returns:
      retained heap size for the given object or 0 if no dominator tree was calculated
      Throws:
      SnapshotException - on an unexpected problem

    • isArray

      public boolean isArray(int objectId)
      Description copied from interface: ISnapshot
      Returns true if the object by this id is an array.

      Performance: Very fast.

      Specified by:
      isArray in interface ISnapshot
      Parameters:
      objectId - id of object to test for being an array (and so an IArray).
      Returns:
      true if it is an array

    • isClass

      public boolean isClass(int objectId)
      Description copied from interface: ISnapshot
      Returns true if the object by this id is a class.

      Performance: Very fast.

      Specified by:
      isClass in interface ISnapshot
      Parameters:
      objectId - id of object to test for being a class (and so an IClass).
      Returns:
      true if it is a class

    • isGCRoot

      public boolean isGCRoot(int objectId)
      Description copied from interface: ISnapshot
      Returns true if the object by this id is a garbage collection root.

      Performance: Very fast.

      Specified by:
      isGCRoot in interface ISnapshot
      Parameters:
      objectId - id of object to test for being a GC root
      Returns:
      true if it is a GC root

    • mapAddressToId

      public int mapAddressToId(long objectAddress) throws SnapshotException
      Description copied from interface: ISnapshot
      Map object address (memory address where the object was stored) to object id (snapshot internal identity assigned during parsing).

      Performance: Fast - binary search in memory.

      Specified by:
      mapAddressToId in interface ISnapshot
      Parameters:
      objectAddress - address of object you want the id for
      Returns:
      object id
      Throws:
      SnapshotException - if the object address is not found.

    • dispose

      public void dispose()
      Description copied from interface: ISnapshot
      Dispose the whole snapshot.

      Please call this method prior to dropping the last reference to the snapshot as this method ensures the proper return of all resources (e.g. main memory, file and socket handles...). After calling this method the snapshot can't be used anymore.

      Specified by:
      dispose in interface ISnapshot

    • resolveClassHierarchy

      public List<IClass> resolveClassHierarchy(int classIndex)
      Finds the class and all its superclasses.
      Parameters:
      classIndex - the class ID
      Returns:
      all the classes

    • isClassLoader

      public boolean isClassLoader(int objectId)
      performance improved check if the object is a class loader
      Specified by:
      isClassLoader in interface ISnapshot
      Parameters:
      objectId - id of object to test for being a class loader (and so an IClassLoader).
      Returns:
      true if it is a class

    • getClassLoaderLabel

      public String getClassLoaderLabel(int objectId)
      Finds the name associated with a class loader.
      Parameters:
      objectId - the class loader
      Returns:
      the name

    • setClassLoaderLabel

      public void setClassLoaderLabel(int objectId, String label)
      Associates a class loader with a name
      Parameters:
      objectId - the class loader
      label - the name

    • getIndexManager

      public IndexManager getIndexManager()
      Gets all the indexes for the snapshot.
      Returns:
      the manager of the indexes

    • getHeapObjectReader

      public IObjectReader getHeapObjectReader()
      Gets the reader for the particular snapshot type to read individual objects.
      Returns:
      the reader

    • getRetainedSizeCache

      public RetainedSizeCache getRetainedSizeCache()
      The cache to speed the finding of the retained size for each object.
      Returns:
      the cache

    • getRootsPerThread

      public HashMapIntObject<HashMapIntObject<XGCRootInfo[]>> getRootsPerThread()
      Gets the roots per thread from the variables on the stack frames.
      Returns:
      a map between the thread ID and the GC root information

    • getSnapshotAddons

      public <A> A getSnapshotAddons(Class<A> addon) throws SnapshotException
      Get additional JVM information, if available.

      A known type is UnreachableObjectsHistogram. Extra information can be obtained from an implementation of IObjectReader.getAddon(Class).

      Specified by:
      getSnapshotAddons in interface ISnapshot
      Type Parameters:
      A - the type of the result
      Parameters:
      addon - the type of the data. For example, UnreachableObjectsHistogram.class
      Returns:
      the extra data
      Throws:
      SnapshotException - if there is a problem retrieving the information

    • getThreadStack

      public IThreadStack getThreadStack(int objectId) throws SnapshotException
      Description copied from interface: ISnapshot
      Get a the stack trace information for a given thread object, if thread stack information is available in this snapshot.

      Specified by:
      getThreadStack in interface ISnapshot
      Parameters:
      objectId - the object ID of the thread
      Returns:
      IThreadStack - an object representing the call stack of the thread. Returns null if no info is available for the object, or no stack info is available at all
      Throws:
      SnapshotException - if there is a problem retrieving the information