Package com.luciad.format.database

Class TLcdDatabaseReadOnlyModel

java.lang.Object
com.luciad.model.ALcdModel
com.luciad.format.database.TLcdDatabaseReadOnlyModel
All Implemented Interfaces:
ILcd2DBoundsIndexedModel, ILcd2DBoundsInteractable, ILcdModel, ILcdBounded, ILcdDisposable, Serializable, AutoCloseable
public class TLcdDatabaseReadOnlyModel extends ALcdModel implements ILcd2DBoundsIndexedModel
This class presents the contents of a database table containing geometries, as an ILcd2DBoundsIndexedModel. The elements in the model can be retrieved sequentially or based on a query. It it a read-only model, so elements cannot be added, changed, or deleted.

The model elements are ILcdShape objects. Typical database models contain the following elements: ILcdPoint, ILcdPolypoint, ILcdPolyline, ILcdPolygon, ILcdComplexPolygon, ILcdArc, ILcdBounds, ILcdCircle, and ILcdShapeList.

The elements are retrieved from the database as they are needed. The entire database will therefor not be loaded when the user is only working on a small part of it. The connection to the database has to remain available while the model is being accessed.

The database is best not changed by other database users, as the TLcdDatabaseModel will not be aware of these changes. The database may become inconsistent if the same geometry is altered by different users at the same time. If the database is changed by another user anyway, calling the clearCaches() method will clear the object's caches, so that it will be synchronized with the database.

See Also:

  • Constructor Details

    • TLcdDatabaseReadOnlyModel

      public TLcdDatabaseReadOnlyModel()
      Constructs an empty TLcdDatabaseModel.

  • Method Details

    • setClassTraceOn

      public static void setClassTraceOn(boolean aClassTraceOn)
      Deprecated.
      This method has been deprecated. It is recommended to use the standard Java logging framework directly.
      Enables tracing for all instances of this class. If the argument is true then all log messages are recorded, otherwise only the informative, warning and error messages are recorded.
      Parameters:
      aClassTraceOn - if true then all log messages are recorded, otherwise only the informative, warning and error messages are recorded.

    • isTraceOn

      public boolean isTraceOn()
      Deprecated.
      This method has been deprecated. It is recommended to use the standard Java logging framework directly.
      Returns true if tracing is enabled for this class.
      Overrides:
      isTraceOn in class ALcdModel
      Returns:
      true if tracing is enabled for this class, false otherwise.

    • setModelDescriptor

      public void setModelDescriptor(ILcdModelDescriptor aModelDescriptor)
      Description copied from class: ALcdModel
      Sets the model descriptor providing meta information about this model and its elements.
      Overrides:
      setModelDescriptor in class ALcdModel
      Parameters:
      aModelDescriptor - a data descriptor for this model. Must be a ILcdDatabaseModelDescriptor.
      See Also:

    • setMaxCacheSize

      public void setMaxCacheSize(int aMaxCacheSize)

    • getMaxCacheSize

      public int getMaxCacheSize()

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • clearCache

      public void clearCache()
      Clears any cached elements, so all requested elements will be reloaded from the database.

    • elements

      public ILcdAutoCloseableEnumeration elements(Enumeration aKeyEnumeration) throws IOException
      Retrieves the geometries with the given keys.
      Parameters:
      aKeyEnumeration - the Enumeration of the keys of objects to retrieve.
      Returns:
      an ILcdAutoCloseableEnumeration of objects with the given keys.
      Throws:
      IOException

    • canAddElement

      public boolean canAddElement(Object aObject)
      Description copied from class: ALcdModel
      Returns true if the specified element can be added to this model, false otherwise.

      Note that this method generally does not validate whether the specified element is expressed in the same model reference as this model. It is the responsibility of the user of this model to make sure this precondition is fulfilled when an element is added to this model.

      This implementation always returns false.

      Specified by:
      canAddElement in interface ILcdModel
      Overrides:
      canAddElement in class ALcdModel
      Parameters:
      aObject - the element to be verified.
      Returns:
      true if the specified element can be added to this model, false otherwise.

    • canRemoveElement

      public boolean canRemoveElement(Object aObject)
      Description copied from class: ALcdModel
      Returns true if the specified element can be removed from this model, false otherwise. Note that this method generally does not check whether the specified element is actually contained in this model.

      This implementation always returns false.

      Specified by:
      canRemoveElement in interface ILcdModel
      Overrides:
      canRemoveElement in class ALcdModel
      Parameters:
      aObject - the element to be verified.
      Returns:
      true if the specified element can be removed from this model, false otherwise.

    • addElement

      public void addElement(Object aObject, int aFireEventMode)
      Description copied from class: ALcdModel
      Adds the specified element to this model.

      Models that support this operation may place limitations on what elements may be added to this model. For example, implementations that are based on a spatial indexing structure will require that elements implement ILcdBounded.

      When adding an element, the user should make sure that canAddElement(aElement) holds, and that the element's geometry is expressed in the same model reference as this model. It is generally undefined what happens if an invalid element is added.

      Implementations of this interface should clearly specify in their documentation any restrictions on what elements may be added. Although it is unspecified what happens if the preconditions are not met, implementations are encouraged to throw meaningful exceptions (for example, NullPointerException, IllegalArgumentException, ClassCastException, UnsupportedOperationException), whenever possible.

      This implementation always throws an UnsupportedOperationException.

      Specified by:
      addElement in interface ILcdModel
      Overrides:
      addElement in class ALcdModel
      Parameters:
      aObject - the element to be added to this model.
      aFireEventMode - the mode for sending out the model change event. This can be FIRE_LATER or NO_EVENT.
      See Also:

    • elementChanged

      public void elementChanged(Object aObject, int aFireEventMode)
      Description copied from class: ALcdModel
      Notifies this model that the specified element has changed.

      This implementation calls TLcdModelChangedEventSupport#elementChanged(Object, int).

      Specified by:
      elementChanged in interface ILcdModel
      Overrides:
      elementChanged in class ALcdModel
      Parameters:
      aObject - the element that has changed.
      aFireEventMode - the mode for sending out the model change event. This can be FIRE_LATER or NO_EVENT.

    • removeElement

      public void removeElement(Object aObject, int aFireEventMode)
      Description copied from class: ALcdModel
      Removes the specified element from this model. If the specified element is not contained in this model, this method has no effect.

      Although it is unspecified what happens if the preconditions are not met, implementations are encouraged to throw meaningful exceptions (for example, NullPointerException, IllegalArgumentException, ClassCastException, UnsupportedOperationException), whenever possible.

      This implementation always throws an UnsupportedOperationException.

      Specified by:
      removeElement in interface ILcdModel
      Overrides:
      removeElement in class ALcdModel
      Parameters:
      aObject - the element to be removed from this model.
      aFireEventMode - the mode for sending out the model change event. This can be FIRE_LATER or NO_EVENT.
      See Also:

    • removeAllElements

      public void removeAllElements(int aFireEventMode)
      Description copied from class: ALcdModel
      Removes all elements from this model.

      If an element cannot be removed, this method will return at the first failure. Succeeding elements won't be removed.

      Although it is unspecified what happens if the preconditions are not met, implementations are encouraged to throw meaningful exceptions (for example, NullPointerException, IllegalArgumentException, ClassCastException, UnsupportedOperationException), whenever possible.

      This implementation iterates over all elements in the model, and calls removeElement(Object, int) for each element to be removed, using event mode NO_EVENT if the specified event mode is NO_EVENT, FIRE_LATER otherwise. If the specified event mode is FIRE_NOW, fireCollectedModelChanges() is called afterwards.

      Specified by:
      removeAllElements in interface ILcdModel
      Overrides:
      removeAllElements in class ALcdModel
      Parameters:
      aFireEventMode - the mode for sending out the model change event. This can be FIRE_LATER or NO_EVENT.

    • elements

      public ILcdAutoCloseableEnumeration elements() throws IllegalStateException
      Description copied from interface: ILcdModel
      Returns an enumeration over all elements of this model. The order in which the elements are enumerated is unspecified by default.
      Specified by:
      elements in interface ILcdModel
      Returns:
      an enumeration over all elements of this model.
      Throws:
      IllegalStateException - if the elements can't be retrieved due to some database error.

    • getBounds

      public ILcdBounds getBounds()
      Description copied from interface: ILcdBounded
      Returns the ILcdBounds by which the geometry of this ILcdBounded object is bounded.

      If the geometry does not allow retrieving valid bounds (for example a polyline with 0 points) the return value is unspecified. It is highly recommended to return an undefined bounds. You can create undefined bounds using the default constructors of TLcdLonLatBounds or TLcdXYBounds.

      Specified by:
      getBounds in interface ILcdBounded
      Returns:
      the ILcdBounds by which the geometry of this ILcdBounded object is bounded.

    • applyOnInteract2DBounds

      public int applyOnInteract2DBounds(ILcdBounds aBounds, boolean aStrictOverlap, ILcdFunction aFunctionToApply, double aPrecisionX, double aPrecisionY) throws IllegalStateException
      Description copied from interface: ILcd2DBoundsIndexedModel
      Applies the specified function to all the model elements of which the 2D bounds overlap with the specified bounds. By default, the order in which the function is applied on the elements is unspecified and depends on the implementation.

      The return value of the specified function is used as a stop criterion: the spatial query is interrupted if the function returns false.

      Specified by:
      applyOnInteract2DBounds in interface ILcd2DBoundsIndexedModel
      Parameters:
      aBounds - the rectangle to test overlap with.
      aStrictOverlap - if false, the spatial search may return more elements than the ones strictly overlapping; if true, the search only returns the elements that are overlapping. The latter mode is more precise, but it may be slower.
      aFunctionToApply - the function to apply on each element that overlaps with the given bounds. The return value of the specified function is used as a stop criterion: the spatial query is interrupted if the function returns false.
      aPrecisionX - the precision required in the x dimension, expressed in model units. For example, for a cartesian grid system expressed in meters, the values should be expressed in meters as well, for a geodetic coordinate system the accuracy values should be expressed in degrees.

      The precision is useful in combination with multi-leveled data (multiple representations of the same object, but with varying accuracy), so that the most appropriate accuracy level can be used. 0 means best possible accuracy, but it might trigger lazy-loaded implementations to load lots of data.

      aPrecisionY - the precision required in the y dimension, expressed in model units.
      Returns:
      the number of elements to which the ILcdFunction has been applied.
      Throws:
      IllegalStateException

    • applyOnInteract2DBounds

      public int applyOnInteract2DBounds(ILcdBounds aBounds, boolean aStrictInteract, ILcdFunction aFunctionToApply, double aPrecisionX, double aPrecisionY, double aMinSizeX, double aMinSizeY, boolean aIncludePoints) throws IllegalStateException
      Description copied from interface: ILcd2DBoundsInteractable
      Applies the specified function to all the elements of which the 2D bounds overlap with the specified bounds. The order in which the function is applied on the elements is unspecified and depends on the implementation.

      Only elements that have at least the specified minimal size in the x dimension or in the y dimension are considered. This can be useful for quickly eliminating elements that are too small to be visible in a view, for instance. If required, an exception can be made for point elements, which have a size of 0 by 0. They can be forced to be considered, even though they would always be rejected as being too small for any sizes larger than 0.

      The return value of the specified function is used as a stop criterion: the spatial query will be interrupted as soon as the function returns false for an element it was applied on.

      Specified by:
      applyOnInteract2DBounds in interface ILcd2DBoundsIndexedModel
      Specified by:
      applyOnInteract2DBounds in interface ILcd2DBoundsInteractable
      Parameters:
      aBounds - the rectangle to test overlap with.
      aStrictInteract - if false, the spatial search may return more elements than the ones strictly overlapping; if true, the search only returns the elements that are overlapping. The latter mode is more precise, but it may be slower.
      aFunctionToApply - the function to apply on each element that overlaps with the given bounds.
      aPrecisionX - the precision required in the x dimension, expressed in model units. For example, for a cartesian grid system expressed in meters, the values should be expressed in meters as well, for a geodetic coordinate system the accuracy values should be expressed in degrees.

      The precision is useful in combination with multi-leveled data (multiple representations of the same object, but with varying accuracy), so that the most appropriate accuracy level can be used. 0 means best possible accuracy, but it might trigger lazy-loaded implementations to load lots of data.

      aPrecisionY - the precision required in the y dimension, expressed in model units.
      aMinSizeX - the minimal element size in the x dimension (as in ILcdBounds.getWidth()), expressed in model units. Elements that are smaller than this size will be skipped. This may, for example, be useful when improving the efficiency of painting elements by skipping elements that are smaller than some threshold (e.g. one pixel, converted to model units).
      aMinSizeY - the minimal element size in the y dimension (as in ILcdBounds.getHeight()), expressed in model units.
      aIncludePoints - if true, zero-sized elements (points) are considered as well, even though they might be smaller than the minimum size.
      Returns:
      the number of elements to which the ILcdFunction has been applied.
      Throws:
      IllegalStateException - if the elements can't be retrieved due to some database error.

    • dispose

      public void dispose()
      Disposes of this TLcdDatabaseModel and releases the JDBC system resources that it is using.
      Specified by:
      dispose in interface ILcdDisposable
      Specified by:
      dispose in interface ILcdModel
      Overrides:
      dispose in class ALcdModel
      See Also: