| 1 | package de.uka.ipd.sdq.sensorframework.filter; |
| 2 | |
| 3 | import java.util.AbstractCollection; |
| 4 | import java.util.ArrayList; |
| 5 | import java.util.Collection; |
| 6 | import java.util.Iterator; |
| 7 | |
| 8 | import de.uka.ipd.sdq.sensorframework.entities.Measurement; |
| 9 | |
| 10 | /** |
| 11 | * Superclass for all filtered collection in the SensorFramework. |
| 12 | * @author Roman Andrej |
| 13 | */ |
| 14 | public abstract class AbstractMeasurementsCollection extends |
| 15 | AbstractCollection<Measurement> { |
| 16 | |
| 17 | /** Original collection. */ |
| 18 | protected Collection<Measurement> originalMeasurements = null; |
| 19 | |
| 20 | /** Filtered collection. |
| 21 | * TODO clarify whether it contains items filtered AWAY |
| 22 | * rather than items left AFTER filtering. |
| 23 | * TODO why is this private, not protected? |
| 24 | */ |
| 25 | private ArrayList<Measurement> filteredItems = null;//why not a Collection, too? |
| 26 | |
| 27 | /** |
| 28 | * Initializes a new AbstractMeasurementsCollection. |
| 29 | */ |
| 30 | public AbstractMeasurementsCollection(){ |
| 31 | } |
| 32 | |
| 33 | /** |
| 34 | * Initializes a new AbstractMeasurementsCollection. |
| 35 | * |
| 36 | * @param originalMeasurements |
| 37 | * The associated measurements. |
| 38 | */ |
| 39 | public AbstractMeasurementsCollection( |
| 40 | Collection<Measurement> originalMeasurements) { |
| 41 | this.originalMeasurements = originalMeasurements; |
| 42 | } |
| 43 | |
| 44 | /** {@inheritDoc} |
| 45 | */ |
| 46 | @Override |
| 47 | public Iterator<Measurement> iterator() { |
| 48 | if (filteredItems == null) { |
| 49 | filteredItems = new ArrayList<Measurement>(); |
| 50 | applyFilter(filteredItems); |
| 51 | } |
| 52 | return new Iterator<Measurement>(){ |
| 53 | Iterator<Measurement> it = originalMeasurements.iterator(); |
| 54 | int currentOriginal = 0, alreadyReturned = 0; |
| 55 | |
| 56 | public boolean hasNext() { |
| 57 | return currentOriginal < originalMeasurements.size() && alreadyReturned < size(); |
| 58 | } |
| 59 | |
| 60 | public Measurement next() { |
| 61 | Measurement next; |
| 62 | while ( filteredItems.contains(next = it.next()) ){ |
| 63 | currentOriginal++; |
| 64 | } |
| 65 | currentOriginal++; alreadyReturned++; |
| 66 | return next; |
| 67 | } |
| 68 | |
| 69 | public void remove() {//TODO add logging here |
| 70 | |
| 71 | } |
| 72 | }; |
| 73 | } |
| 74 | |
| 75 | /** The Method filtered the measurements. |
| 76 | * TODO explain what filtering actually means. |
| 77 | * @param filteredItemsList seems to be used as return parameter, |
| 78 | * which contains the elements that are filtered away. |
| 79 | */ |
| 80 | protected abstract void applyFilter(Collection<Measurement> filteredItemsList); |
| 81 | |
| 82 | |
| 83 | /* (non-Javadoc) |
| 84 | * @see java.util.AbstractCollection#size() |
| 85 | */ |
| 86 | @Override |
| 87 | public int size() { |
| 88 | if (filteredItems == null) { |
| 89 | filteredItems = new ArrayList<Measurement>(); |
| 90 | applyFilter(filteredItems); |
| 91 | } |
| 92 | return originalMeasurements.size() - filteredItems.size();//TODO does it make sense? or does "filteredItems" contain items filtered AWAY, not items remaining AFTER filtering? |
| 93 | } |
| 94 | |
| 95 | /** |
| 96 | * Get the original collection. |
| 97 | */ |
| 98 | public Collection<Measurement> getOriginalMeasurements() |
| 99 | throws InstantiationException {//TODO is this really an instantiation problem? Or rather a NullPointerException? |
| 100 | if (originalMeasurements == null) |
| 101 | throw new InstantiationException("No original measurements saved!"); |
| 102 | return originalMeasurements; |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * Resets internally stored filtered items to <code>null</code> |
| 107 | */ |
| 108 | public void resetFilteredItems(){ |
| 109 | filteredItems = null; |
| 110 | } |
| 111 | } |