Heap Walker - Inspections View

  The heap walker reference view conforms to the basic layout of all heap walker views. Also see the help on key concepts for the entire heap walker.
  The inspections view of the heap walker does not show any information on the current object set. Rather, it displays a number of operations that will analyze the current object set in some way. As a result of any inspection, a new object set will be created.
  All available inspections are shown in a selector on the left side, for better usability some of them are ordered into categories. On the right side, the property panel explains the inspection, offers configuration options for the selected inspection and shows a button to calculate it.

Since inspections can be expensive to calculate for large heaps, the results are cached. In this way, you can go back in the history and look at the results of previously calculated inspections without waiting. Inspections with cached results show a  "Calculated" status in the property panel.

  After an inspection has been calculated, the view change dialog will be shown. By default, the reference view is recommended.

An inspection can partition the calculated object set into groups. Groups are shown in a table at the top of the heap walker. Initially, the first row in the group table is selected. By changing the selection, you change the current object set. For example, the "Duplicate strings" inspection shows the duplicate string values as groups. If you are in the reference view, you can then see the java.lang.String instances with the selected string value below.

Beside the group name column in the group table there are the following sortable columns:

  • Priority
    Each inspection that creates groups decides which groups are most important in the context of the inspection. Since this does not always correspond to a sort order of one of the other columns, the priority column contains a numeric value that enforces that sort order. By default, the group table is sorted by this column.
  • Instance Count
    The number of objects that are contained in the group. If you select the group, the current object set below will have this number of objects.
  • Shallow Size
    The combined shallow size of the objects that are contained in the group. If you select the group, the current object set below will have this shallow size. For an explanation of sizes of object sets, please see the heap walker overview.

You can search in the group table by typing into it or right-clicking it and selecting the Find action from the context menu. The group table can be exported to HTML or CSV, by choosing Export View from its context menu. Note that the group table will not be exported when you export the current heap walker view with the export action in the tool bar.

The group selection is not a separate selection step in the heap walker, but it becomes part of the selection step made by the inspection. You can see the group selection in the selection step pane at the bottom. When you change the group selection, the selection step pane is updated immediately.