Examples with Optimization org.apache.sis.filter.Optimization used on opensource projects

Example 1 with Optimization

use of org.apache.sis.filter.Optimization in project sis by apache.

the class RegistryTestCase method testFeatureOptimization.

/**
 * Tests {@link Optimization} on an arbitrary expression on feature instances.
 */
@Test
public void testFeatureOptimization() {
    geometry = library.createPoint(10, 30);
    setGeometryCRS(HardCodedCRS.WGS84_LATITUDE_FIRST);
    function = factory.function("ST_Union", factory.property(P_NAME), factory.literal(geometry));
    final Optimization optimization = new Optimization();
    final FeatureTypeBuilder ftb = new FeatureTypeBuilder();
    ftb.addAttribute(library.pointClass).setName(P_NAME).setCRS(HardCodedCRS.WGS84);
    optimization.setFeatureType(ftb.setName("Test").build());
    final Expression<? super AbstractFeature, ?> optimized = optimization.apply(function);
    assertNotSame("Optimization should produce a new expression.", function, optimized);
    /*
         * Get the second parameter, which should be a literal, and get the point coordinates.
         * Verify that the order is swapped compared to the order at the beginning of this method.
         */
    final Object literal = optimized.getParameters().get(1).apply(null);
    final DirectPosition point = library.castOrWrap(literal).getCentroid();
    assertArrayEquals(new double[] { 30, 10 }, point.getCoordinate(), STRICT);
}

Example 2 with Optimization

use of org.apache.sis.filter.Optimization in project sis by apache.

the class FeatureStream method filter.

/**
 * Returns a stream with features of this stream that match the given predicate.
 * If the given predicate is an instance of {@link Filter}, then this method tries
 * to express the filter using SQL statements.
 */
@Override
public Stream<AbstractFeature> filter(final Predicate<? super AbstractFeature> predicate) {
    ArgumentChecks.ensureNonNull("predicate", predicate);
    if (predicate == Filter.include())
        return this;
    if (predicate == Filter.exclude())
        return empty();
    if (isPagined()) {
        /*
             * Offset/limit executed before the filter. Can not continue to build an SQL statement
             * because the SQL `OFFSET ... FETCH NEXT` clause would be executed after the filter.
             */
        return delegate().filter(predicate);
    }
    if (!(predicate instanceof Filter<?>)) {
        hasPredicates = true;
        return super.filter(predicate);
    }
    if (selection == null) {
        selection = new SelectionClause(table);
        filterToSQL = table.database.getFilterToSupportedSQL();
    }
    /*
         * Simplify/optimize the filter (it may cause `include` or `exclude` filters to emerge) and try
         * to convert the filter to SQL statements. This is not necessarily an all or nothing operation:
         * if we have a "F₀ AND F₁ AND F₂" chain, it is possible to have some Fₙ as SQL statements and
         * other Fₙ executed in Java code.
         */
    final Optimization optimization = new Optimization();
    optimization.setFeatureType(table.featureType);
    Stream<AbstractFeature> stream = this;
    for (final Filter<? super AbstractFeature> filter : optimization.applyAndDecompose((Filter<? super AbstractFeature>) predicate)) {
        if (filter == Filter.include())
            continue;
        if (filter == Filter.exclude())
            return empty();
        if (!selection.tryAppend(filterToSQL, filter)) {
            // Delegate to Java code all filters that we can not translate to SQL statement.
            stream = super.filter(filter);
            hasPredicates = true;
        }
    }
    return stream;
}

Example 3 with Optimization

use of org.apache.sis.filter.Optimization in project sis by apache.

the class RegistryTestCase method testOptimization.

/**
 * Tests {@link Optimization} on an arbitrary expression.
 * This method uses data tested by {@link #testTransform()}.
 */
@Test
public void testOptimization() {
    geometry = library.createPoint(10, 30);
    setGeometryCRS(HardCodedCRS.WGS84);
    function = factory.function("ST_Transform", factory.literal(geometry), factory.literal(HardCodedCRS.WGS84_LATITUDE_FIRST));
    assertPointEquals(function.apply(null), HardCodedCRS.WGS84_LATITUDE_FIRST, 30, 10);
    /*
         * Optimization should evaluate the point immediately.
         */
    final Expression<? super AbstractFeature, ?> optimized = new Optimization().apply(function);
    assertNotSame("Optimization should produce a new expression.", function, optimized);
    assertInstanceOf("Expected immediate expression evaluation.", Literal.class, optimized);
    assertPointEquals(((Literal) optimized).getValue(), HardCodedCRS.WGS84_LATITUDE_FIRST, 30, 10);
}

Example 4 with Optimization

use of org.apache.sis.filter.Optimization in project sis by apache.

the class SelectionClauseWriterTest method testGeometricFilterWithTransform.

/**
 * Verifies that a spatial operator transforms literal value before-hand if possible.
 */
private void testGeometricFilterWithTransform() {
    final GeneralEnvelope bbox = new GeneralEnvelope(HardCodedCRS.WGS84_LATITUDE_FIRST);
    bbox.setEnvelope(-10, 20, -5, 25);
    Filter<AbstractFeature> filter = FF.intersects(FF.property("BETA"), FF.literal(bbox));
    final Optimization optimization = new Optimization();
    optimization.setFeatureType(table.featureType);
    verifySQL(optimization.apply(filter), "ST_Intersects(\"BETA\", " + "ST_GeomFromText('POLYGON ((20 -10, 25 -10, 25 -5, 20 -5, 20 -10))'))");
}

Example 5 with Optimization

use of org.apache.sis.filter.Optimization in project sis by apache.

the class FeatureQuery method execute.

/**
 * Applies this query on the given feature set.
 * This method is invoked by the default implementation of {@link FeatureSet#subset(Query)}.
 * The default implementation executes the query using the default {@link java.util.stream.Stream} methods.
 * Queries executed by this method may not benefit from accelerations provided for example by databases.
 * This method should be used only as a fallback when the query can not be executed natively
 * by {@link FeatureSet#subset(Query)}.
 *
 * <p>The returned {@code FeatureSet} does not cache the resulting {@code Feature} instances;
 * the query is processed on every call to the {@link FeatureSet#features(boolean)} method.</p>
 *
 * @param  source  the set of features to filter, sort or process.
 * @return a view over the given feature set containing only the filtered feature instances.
 * @throws DataStoreException if an error occurred during creation of the subset.
 *
 * @see FeatureSet#subset(Query)
 * @see CoverageQuery#execute(GridCoverageResource)
 *
 * @since 1.2
 */
protected FeatureSet execute(final FeatureSet source) throws DataStoreException {
    ArgumentChecks.ensureNonNull("source", source);
    final FeatureQuery query = clone();
    if (query.selection != null) {
        final Optimization optimization = new Optimization();
        optimization.setFeatureType(source.getType());
        query.selection = optimization.apply(query.selection);
    }
    return new FeatureSubset(source, query);
}