Class FeatureCollectionTools

java.lang.Object
org.openjump.core.apitools.ToolToMakeYourLifeEasier
org.openjump.core.apitools.FeatureCollectionTools
public class FeatureCollectionTools extends ToolToMakeYourLifeEasier
Class to speed up handling of FeatureCollections (or lists of features) during progamming by implementing a set of common tasks. Most functions can be used in a static way, but on the other hand for each FeatureCollection a instance of this class can be invoked. This might be more convenient, if there is more than one thing to do with the same feature collection.
Version:
$Rev$ [sstein] - 22.Feb.2009 - modified to work in OpenJUMP
Author:
Ole Rahn, Stefan Steiniger

FH Osnabrück - University of Applied Sciences Osnabrück,
Project: PIROL (2005),
Subproject: Daten- und Wissensmanagement

  • Field Details

  • Constructor Details

    • FeatureCollectionTools

      public FeatureCollectionTools(FeatureCollection fc)

    • FeatureCollectionTools

      public FeatureCollectionTools(List<Feature> fcl)

  • Method Details

    • getFeature

      public Feature getFeature(int fid)
      gets the Feature with the given FID.
      Parameters:
      fid - FID to look for
      Returns:
      the feature

    • getFeatureFromCollection

      public static Feature getFeatureFromCollection(List<Feature> features, int fid)
      Get the feature with the specified ID from the List
      Parameters:
      features - array with Feature objects
      fid - the feature ID we are looking for
      Returns:
      feature with specified FID if exists, else null

    • getFeatureFromCollection

      public static Feature getFeatureFromCollection(Feature[] features, int fid)
      Get the feature with the specified ID from the array
      Parameters:
      features - array with Feature objects
      fid - the feature ID we are looking for
      Returns:
      feature with specified FID if exists, else null

    • cloneFeatureCollection

      public static PirolFeatureCollection cloneFeatureCollection(FeatureCollection fc)
      deep copies a the FeatureSchema, the Features and their Geometries
      Parameters:
      fc - the FeatureCollection to copy
      Returns:
      the new copied FeatureCollection

    • getFeatureFromCollection

      public static Feature getFeatureFromCollection(FeatureCollection features, int fid)
      Get the feature with the specified ID from the FeatureCollection
      Parameters:
      features - array with Feature objects
      fid - the feature ID we are looking for
      Returns:
      feature with specified FID if exists, else null

    • getAritmeticMiddleForAttribute

      public static double getAritmeticMiddleForAttribute(Feature[] features, String attr)
      Parameters:
      features - list of features to calculate the mean for
      attr - name of attribute to calculate the mean for
      Returns:
      the mean (double because a mean of integers will very likely be a double)

    • getMeanOrModeForAttributes

      public static Object[] getMeanOrModeForAttributes(Feature[] features, String[] attrs)
      Method to calculate means (or modes) for the attributes given. If means or modes are calulated depends on the attribute type of each given attribute. This method is hopefully faster, than calculation each mean (mode) in an extra loop, if there are more means (modes) to calculate than one...
      Parameters:
      features - list of features to calculate mean/modes for
      attrs - array of attribute names to calculate mean/modes for
      Returns:
      array of objects, representing means (or modes) --> e.g. Double, Integer or String objects.

    • getEnvelopeForFeatures

      public static org.locationtech.jts.geom.Envelope getEnvelopeForFeatures(Feature[] features)
      Creates an envelope object for the features in the given array. This is an easy way to get an envelope for a subset of a layer's features.
      Parameters:
      features - array of Feature object to create an envelope for
      Returns:
      the envelope containing the given features

    • getAritmeticMiddleForAttribute

      public static double getAritmeticMiddleForAttribute(List<Feature> features, int attr)
      Parameters:
      features - list of features to calculate the mean for
      attr - index of attribute to calculate the mean for
      Returns:
      the mean (double because a mean of integers will very likely be a double)

    • getAritmeticMiddleForAttribute

      public static double getAritmeticMiddleForAttribute(Feature[] featArray, int attr)
      Parameters:
      featArray - array of features to calculate the mean for
      attr - index of attribute to calculate the mean for
      Returns:
      the mean (double because a mean of integers will very likely be a double)

    • getCenterOfMass

      public static org.locationtech.jts.geom.Geometry getCenterOfMass(Feature[] features)
      Calculates the center of mass for the gives features' geometries. It's like getCentroid(), but puts out one center of mass for N features instead of N centers for N features.
      Parameters:
      features - the features
      Returns:
      the point, representing the center of mass

    • getSetOfDifferentAttributeValues

      public static Set getSetOfDifferentAttributeValues(Feature[] features, String attr)
      Parameters:
      features - list of features
      attr - name of attribute
      Returns:
      number of differnt values in the given features attributes or -1 if an error occurs

    • getSetOfDifferentAttributeValues

      public static Set<Object> getSetOfDifferentAttributeValues(Feature[] features, int attr)
      Parameters:
      features - list of features
      attr - index of attribute
      Returns:
      number of differnt values in the given features attributes or -1 if an error occurs

    • getNumOfDifferentAttributeValues

      public static int getNumOfDifferentAttributeValues(Feature[] features, String attr)
      Parameters:
      features - list of features
      attr - name of attribute
      Returns:
      number of differnt values in the given features attributes or -1 if an error occurs

    • getNumOfDifferentAttributeValues

      public static int getNumOfDifferentAttributeValues(Feature[] features, int attr)
      Parameters:
      features - list of features
      attr - index of attribute
      Returns:
      number of differnt values in the given features attributes or -1 if an error occurs

    • getModusForAttribute

      public static Object getModusForAttribute(Feature[] features, String attr)
      Parameters:
      features - list of features to calculate the mode for
      attr - name of attribute to calculate the mode for
      Returns:
      the mode

    • getValueAppearancesCount

      public static HashMap<Object,Integer>[] getValueAppearancesCount(Feature[] features, int[] attrs)
      Counts the number of appearances of each value of the given attributes within the given features. (Somewhat like a histogram for each given attribute, but each histogram class is just a single value.)
      Parameters:
      features - array of Features to count value appearances for
      attrs - array of attribute indices of attributes to count value appearances for
      Returns:
      Array of mappings of values to number of appearances

    • getModusForAttribute

      public static Object getModusForAttribute(Feature[] features, int attr)
      Parameters:
      features - list of features to calculate the mode for
      attr - index of attribute to calculate the mode for
      Returns:
      the mode

    • deleteFeatures

      public static void deleteFeatures(List<Feature> features, PlugInContext context)
      deletes the given features from the map. It thereby creates an EditTransaction that enables the user to undo the deletion.
      Parameters:
      features - features to be deleted
      context - curr. PlugIn context

    • copyFeature

      public static Feature copyFeature(Feature feat)
      "deep copys" the given Feature
      Parameters:
      feat - the feature to be copied
      Returns:
      copy of the feature

    • copyFeatureAndSetFeatureSchema

      public static Feature copyFeatureAndSetFeatureSchema(Feature feat, FeatureSchema newFs)
      "deep copys" the given Feature and thereby sets the given feature schema. The new FeatureSchema should have the same attribute names for copying. The new FeatureSchmema can have less or more attributes.
      Parameters:
      feat - the feature to be copied
      newFs - the new feature schema
      Returns:
      copy of the feature

    • getUniqueAttributeName

      public String getUniqueAttributeName(String attr)

    • getUniqueAttributeName

      public static String getUniqueAttributeName(FeatureCollection fc, String attr)

    • attributeExistsInSchema

      protected static boolean attributeExistsInSchema(FeatureSchema fs, String attr)

    • addAttributeToFeatureCollection

      public PirolFeatureCollection addAttributeToFeatureCollection(String attr, AttributeType at, Object defaultVal)

    • isAttributeTypeNumeric

      public static boolean isAttributeTypeNumeric(AttributeType at)

    • applyFormulaToFeatureCollection

      public static PirolFeatureCollection applyFormulaToFeatureCollection(FeatureCollection oldFc, AttributeInfo attrInfo, FormulaValue formula, boolean clearOldFeatureCollection)
      Method to apply a given formula to the given, new attribute of the given featureCollection
      Parameters:
      oldFc - old FeatureCollection that will be replaced by the new one
      attrInfo - information for the new attribute
      formula - the parsed formula
      Returns:
      FeatureCollection containing the new attribute

    • addAttributeToFeatureCollection

      public static PirolFeatureCollection addAttributeToFeatureCollection(FeatureCollection fc, AttributeInfo attrInfo)

    • addAttributeToFeatureCollection

      public static PirolFeatureCollection addAttributeToFeatureCollection(FeatureCollection fc, AttributeInfo attrInfo, boolean clearOldFeatureCollection)

    • addAttributeToFeatureCollection

      public static PirolFeatureCollection addAttributeToFeatureCollection(FeatureCollection fc, String attr, AttributeType at, Object defaultVal, boolean clearOldFeatureCollection)
      Method to add a new attribute to an existing FeatureCollection. Since there is no "legal" way to add an attribute to a FeatureCollection, this method creates (and returns) a new FeatureCollection with a new FeatureSchema to do this operation. If a layer is to be manipulated the new FeatureCollection has to be set as THE FeatureCollection for the layer...
      Parameters:
      fc - the old feature collection
      attr - name of the new attribute
      at - type of the new attribute
      defaultVal - the initial value for the attribute, since we do not want NULL values in the attribute table
      clearOldFeatureCollection - if true the old feature collection will be erased to save RAM
      Returns:
      new FeatureCollection with a new FeatureSchema including the new attribute

    • addAttributeToFeatureCollection

      public static PirolFeatureCollection addAttributeToFeatureCollection(FeatureCollection fc, String attr, AttributeType at, Object defaultVal)
      Method to add a new attribute to an existing FeatureCollection. Since there is no "legal" way to add an attribute to a FeatureCollection, this method creates (and returns) a new FeatureCollection with a new FeatureSchema to do this operation. If a layer is to be manipulated the new FeatureCollection has to be set as THE FeatureCollection for the layer...
      Parameters:
      fc - the old feature collection
      attr - name of the new attribute
      at - type of the new attribute
      defaultVal - the initial value for the attribute, since we do not want NULL values in the attribute table
      Returns:
      new FeatureCollection with a new FeatureSchema including the new attribute

    • addAttributesToFeatureCollection

      public PirolFeatureCollection addAttributesToFeatureCollection(List attributeInfos)
      Adds multiple attributes to the FeatureCollection
      Parameters:
      attributeInfos - list containing the attributes (as AttributeInfo objects) to be added
      Returns:
      a new FeatureCollection containing the old and the new attributes
      See Also:

    • addAttributesToFeatureCollection

      public static PirolFeatureCollection addAttributesToFeatureCollection(FeatureCollection fc, List<AttributeInfo> attributeInfos)
      Adds multiple attributes to a FeatureCollection
      Parameters:
      fc - the source feature collection
      attributeInfos - list containing the attributes (as AttributeInfo objects) to be added
      Returns:
      a new FeatureCollection containing the old and the new attributes
      See Also:

    • addAttributesToFeatureCollection

      public static PirolFeatureCollection addAttributesToFeatureCollection(FeatureCollection fc, AttributeInfo[] attributeInfos)

    • addAttributesToFeatureCollection

      public static PirolFeatureCollection addAttributesToFeatureCollection(FeatureCollection fc, AttributeInfo[] attributeInfos, boolean clearOriginalFeatureCollection)
      Adds multiple attributes to a FeatureCollection
      Parameters:
      fc - the source feature collection
      attributeInfos - array containing the attributes to be added
      clearOriginalFeatureCollection - set true, if you want to save RAM by clearing the original FeatureCollection, false if you still want to use it.
      Returns:
      a new FeatureCollection containing the old and the new attributes

    • resizeArray

      public static Object resizeArray(Object oldArray, int newSize)
      Reallocates an array with a new size, and copies the contents of the old array to the new array.
      Parameters:
      oldArray - the old array, to be reallocated.
      newSize - the new array size.
      Returns:
      A new array with the same contents.

    • getMinMaxAttributeValue

      public static double[] getMinMaxAttributeValue(Feature[] featArray, FeatureSchema fs, String attr)

    • getSumAttributeValue

      public static double getSumAttributeValue(Feature[] featArray, FeatureSchema fs, String attr)

    • getMinMaxAttributeValue

      public static double[] getMinMaxAttributeValue(FeatureCollection features, String attr)

    • FeatureCollection2FeatureArray

      public static Feature[] FeatureCollection2FeatureArray(FeatureCollection fc)
      Converts a given FeatureCollection into an array of Feature, that can - by far - be faster iterated.
      Parameters:
      fc - the feature Collection
      Returns:
      an array of the features of the feature collection

    • FeatureCollection2FeatureArray

      public static Feature[] FeatureCollection2FeatureArray(List<Feature> features)
      Converts a given list of features into an array of Feature, that can - by far - be faster iterated.
      Parameters:
      features - list of features
      Returns:
      an array of the features of the feature list

    • convertToPointFeature

      public static ArrayList<Feature> convertToPointFeature(Feature f, boolean accountForRings)
      Extracts all points from an input feature and returns them as list of point features. Note: for closed Geometry objects the start and end point are extracted - i.e. the points may be overlap.
      Parameters:
      f - the Feature to convert
      accountForRings - doesn't add a point for the last coordinate if the geometry is a ring (i.e. first point equals last point)
      Returns:
      list of point features

    • sortFeaturesIntoListsByAttributeValue

      public static Object[] sortFeaturesIntoListsByAttributeValue(FeatureCollection features, String idAttribute)
      Sorts features according to unique attribute values into different lists (on list for each unique attribute). TODO: enable sorting for String values
      Parameters:
      features - the Features to sort
      idAttribute - (must be Double or Integer)
      Returns:
      Object[0]: an Array of ArrayLists containing features, Object[1]: an Array of int values containing the unique values used for sorting. Can return null if wrong AttributeType. E.g. use
      Object[] myReturns = FeatureCollectionTools.sortFeaturesIntoListsByAttributeValue(pointFeatures, idAttribute);
      individualPts = (ArrayList[])myReturns[0];
      int[] uniqueValues = (int[])myReturns[1];
      Note that the order in which the lists are returned is not sorted!

    • getNumericalAttributeValue

      public static double getNumericalAttributeValue(Feature f, String attributeName)
      gets the value of an attribute; it checks if the attribute is of double or int type, otherwise NaN is returned.
      Parameters:
      f - the Feature from which to extract the numeric attribute
      attributeName - name of the attribute to extract
      Returns:
      value as double

    • sortFeatureListByAttributeBeginWithSmallest

      public static ArrayList<Feature> sortFeatureListByAttributeBeginWithSmallest(List<Feature> features, String attributeNameForSorting)
      Sorts a list of features according to the values of a attribute. If values are similar the feature are ordered the same way as in the input list. TODO: this method has been tested only briefly (not exhaustively)
      Parameters:
      features - the features to sort
      attributeNameForSorting - attribute needs to be either Integer or Double
      Returns:
      list of sorted features; the smallest value will be first in the list.

    • getStatistics

      public static StatisticIndices getStatistics(Feature[] featArray, FeatureSchema fs, String attr)